New strategies for smart biointerfaces

Resume : Electro-enzymatic reactions combining oxidoreductase and electrode reactions allow highly selective electrochemical oxidation/reduction reactants under mild reaction conditions, with a very small overpotential. Ezymatic biofuel cells (EBFCs), which convert chemical energy of the oxidation of carbohydrates, such as glucose, in combination with oxygen reduction, under mild condition, come to attract considerable attention as power sources for wearable devices or self-powered sensor-node systems. A combination of electron transfer technology and porous carbon material would be helpful in achieving a much higher and stable current output, thus contributing to a practical advance in the sustainable energy field. Recent developments in EBFCs technology using porous carbon materials, especially Magnesium oxide (MgO)-templated porous carbons (MgOC), are highlighted. To realize high current density per geometric surface area, the concentration of buffer solution should be increased to prevent the local pH change during the electro-enzymatic reaction and also to minimize the ohmic solution resistance in the cell. I will show the effect of characteristics and concentration of electrolyte on the electroenzymatic reaction.

Resume : Enzymatic biofuel cells are eco-friendly power sources that can generate electrical energy (µW-mW) from renewable chemical substrates such as glucose and oxygen, but their stability is a major issue [1]. We report here the characterization and bioelectrocatalysis of ?sweet? redox-active cyclodextrin-coated nanoparticles as electron shuttles [2,3]. We depart from the traditional use of immobilized redox molecules and polymers and instead explore the use of solubilized redox nanoparticles and enzymes in solution for mediated bioelectrocatalysis. This approach can offer possibilities such as refueling, higher biocatalyst concentrations compared to immobilisation methods, size exclusion principles to avoid cross-reactions, and dynamic reactivity based on diffusion and rotation. We will provide spectroscopic and electrochemical data which reveals the controlled self-assembly of nanoparticles with host-guest functionality that can integrate insoluble redox species in aqueous buffer solutions [2-4]. The use of different nanoparticles with bilirubin oxidase and FAD-dependant glucose dehydrogenase enzymes will be demonstrated and compared with classical systems for oxygen reduction and glucose oxidation, respectively. Finally, the new SEFC-carbon nanotube buckypaper biodevice and its use for long-term quasi-continuous power generation will be demonstrated [3,5]. It is feasible that SEFCs, in combination with a boost converter, could be exploited as a new generation of green power sources for low-power electronics such as lab-on-a-chip sensing and data transmission devices.

Resume : Electrical interactions between bacteria and the environment are delicate and essential [1][2]. For instance, by means of electron transfer, bacteria complete respiration on the cell membrane to supply energy for cell growth, proliferation, and maintenance and disturbing electron transfer in bacteria can raise the production of reactive oxygen species (ROS) to hinder growth. In this study [3], an external electrical current is applied to capacitive titania nanotubes doped with carbon (TNT-C) to evaluate the effects on bacteria killing and the underlying mechanism is investigated. When TNT-C is charged, post-charging antibacterial effects proportional to the capacitance are observed. This capacitance-based antibacterial system works well with both direct and alternating current (DC, AC) and the higher discharging capacity in the positive DC (DC ) group leads to better antibacterial performance. Extracellular electron transfer observed during early contact contributes to the surface-dependent post-charging antibacterial process. Physiologically, the electrical interaction deforms the bacteria morphology and elevates the intracellular reactive oxygen species level without impairing the growth of osteoblasts. This is the first systematic study on the post-charging antibacterial properties of biomaterials with tunable capacitance. Our finding spurs the design of light-independent antibacterial materials and provides insights into the use of electricity to modify biomaterials to complement other bacteria killing measures such as light irradiation. References [1] G. M. Wang, H. Q. Feng, et al. ACS Applied Materials and Interfaces, vol. 8, no. 37, pp. 24509 ? 24516 (2016). [2] G. M. Wang, W. H. Jin, et al. Biomaterials, vol. 124, pp. 25 ? 34 (2017). [3] G. M. Wang, H. Q. Feng, et al. Nature Communications, vol. 9, Paper 2055 (2018).

Resume : In this study, we employed a novel one step electrospinning process to fabricate poly(ethylene oxide) (PEO)/poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT:PSS) core/shell nanofiber structures with improved water resistance and good electrochemical properties. We then integrated a biocompatible polymer coating with three-dimensional (3D) PEDOT-based nanofiber devices for dynamic control over the capture/release performance of rare circulating tumor cells (CTCs) , as well as the label-free detection by using organic electrochemical transistors (OECTs). The detailed capture/release behavior of the circulating tumor cells was studied using an organic bioelectronic platform comprising PEO/PEDOT:PSS nanofiber mats with 3 wt % (3-glycidyloxypropyl)trimethoxysilane as an additive. We have demonstrated that these nanofiber mats deposited on five-patterned indium tin oxide finger electrodes are excellent candidates for use as functional bioelectronic interfaces for the isolation, detection, sequential collection, and enrichment of rare CTCs through electrical activation of each single electrode. This combination behaved as an ideal model system displaying a high cell-capture yield for antibody-positive cells while resisting the adhesion of antibody-negative cells. Taking advantage of the electrochemical doping/dedoping characteristics of PEDOT:PSS materials, the captured rare cells could be electrically triggered release through the desorption phenomena of PLL-g-PEG-biotin on device surface. More than 90% of the targeted cancer cells were captured on the 3D PEDOT-based nanofiber microfluidic device; over 87% of captured cancer cells were subsequently released for collection; approximately 80% of spiked cancer cells could be collected in a 96-well plate. For the OECT design, it was demonstrated for monitoring CTC-capture performance and identifying cancer cell phenotypes. This 3D PEDOT-based bioelectronic device approach appears to be an economical route for the large-scale preparation and detection of systems for enhancing the downstream characterization of rare CTCs.

Resume : The interaction of biomolecules with solid surfaces ? in particular, carbon surfaces ? has been of great interest for both fundamental and applied aspects. The diversity of carbon allotropes gives access to a large variety of structural and textural properties, while the complexity of biomolecules (e.g. polysaccharides, cofactors, proteins) provides specific functionalities. In this presentation, I will discuss few examples of biomolecule-carbon interfaces for the design of functional materials. In a first example, I will present the preparation of aqueous colloidal suspensions obtained via the co-dispersion of multi-walled carbon nanotubes (MWCNTs) and polysaccharides, e.g. cellulose. Such dispersions were successfully employed to stabilize oil-in-water (smart) interfaces and elaborate hierarchical composite structures, e.g. lace-like hollow spheres. In a second example, I will introduce the importance of biomolecule-carbon interfaces in enzymatic catalysis and electrocatalysis, via pore confinement and surface modification. In our group, a particular attention has been given to formate dehydrogenases (FDHs), which require the loosely bound cofactor nicotinamide adenine dinucleotide (NAD). We recently developed carbon-based flow through enzymatic reactors for the production of formate from carbon dioxide and a novel method to covalently immobilize NAD onto carbonaceous materials.

Resume : Despite research and clinical efforts of the last decades, there is no cure for spinal cord injury to date. Remarkable drawbacks of this type of lesions include dramatic changes in the quality of life and life expectancy of patients, affected by a disruption of neural connections through the spinal cord. Aiming to provide more effective therapeutic alternatives, neuroscience, nanotechnology, and materials science are working together on the development of novel biocompatible implants capable of improving the functionality of the damaged neural tissue at the lesion. In the ByAxon Project, we have developed a new generation of 2D nanoelectrodes consisted of vertically arranged metal nanowires (NWs) made of Ni and Au and grown by template-assisted electrodeposition over a flexible gold base. The behavior of neural progenitor cells isolated from rat embryos has been studied in culture on these substrates with focus on cell adhesion, viability, morphology, and differentiation. Neural cells properly adhere and spread, closely interacting with the metallic NWs. After 2 weeks, these cells are able to form dense neural networks with high viability and mainly composed of neurons. These results encourage further research in the use of these materials as stimulating nanoelectrodes for the development of a local bypass directly working at the spinal cord. This project is funded by the European Union?s Horizon 2020 research and innovation programme under grant agreement No 737116.

Resume : The concept to artificially reconstitute an electroactive biofilm is a recent strategy used in order to optimize extracellular electron transfer (EET) reactions and mimic natural biofilms [1-3]. Those artificial biofilms would greatly benefit to electrochemical bacterial devices such as microbial fuel cell or sustain biosensors. They would also benefit to microbial electrosynthesis or electrocatalysis. Recent studies have reported the application of microbial electrochemical systems in biochemical production of ethanol or hydrogen and to the bioremediation of sulphate or nitrogen species in aqueous environment. In this work, we studied the direct electron transfer reactions occurring in a biocomposite resulting from the self-assembly of microbes with carbon nanomaterials and proteins. Both bacteria and yeast cells have been evaluated. For example, with Shewanella oneidensis MR1, the onset potential observed for fumarate electroreduction was found very close to 0.030 V vs. SHE, the formal redox potential for fumarate/succinate interconversion and a maximum current density in the range of 1 A m-2 was reached with this electroactive artificial biofilm. In this communication, we will describe and discuss this new way to promote direct electron transfer reactions in electroactive artificial biofilms. [1] S. Pinck et al., Bioelectrochemistry, 118 (2017) 131?138. [2] S. Pinck et al., Bioelectrochemistry, 124 (2018) 185?194. [3] S. Pinck et al., ChemElectroChem, revision submitted. This work was supported by the French PIA project « Lorraine Université d?Excellence », reference ANR-15-IDEX-04-LUE.

Resume : A major challenge for bioelectronics lies in the monitoring of electrical activities of neurons at the single cell level, both with high resolution of measure and applied simultaneously to multiple locations. One breakthrough is the development of a new class of devices that take advantage of miniaturization in electronics, thereby refining the investigation resolution. Here, we present a bio-platform with 3D passive nanoprobes based on nanostructures with very high surface-to-volume ratio. The device is created using a large-scale fabrication process based on conventional silicon processing. The electrodes are composed of several nanowires, where the design (size, pitch …) has been optimized to favour the engulfment of the cell. We demonstrate that the surface engineering of the probes at nanoscale leads to drastic reduction in the electrode impedance. This key factor is able to enhance the signal resolution 200-fold when compared to conventional MEA planar technology. We could register spontaneous activity of primary rat neurons with record amplitudes, not only for action potentials (ten of mV), but also smaller signals (Pre- and Post-Synaptic Potentials (PSPs)) usually invisible with planar MEAs. Moreover, we present the impact on neuronal activity of several chemical stimulations (chemical blockers and Long Term Potentiation inducers), as well as of molecules involved in Alzheimer’s disease (Amyloid Beta Peptide).

Resume : Science is facing the challenge of directly interact with neural tissues to perform electrical stimulation of the neural activity in zones that have been compromised. Spinal cord stimulators, cortical electrodes or retina implants, are some of the devices inspired by this technology. These electrode-based devices nowadays present size, morphology and rigidity issues that unleashes an immunologic response that inactivates them. We are developing new biocompatible flexible electrodes with nanostructured surface. They are composed by a flexible Au thin sheet with one of its surfaces covered by a network of metallic vertical NWs. The aspect-ratio of the NWs ensures high contact with neural tissue and their size in the nanoscale minimises the damage. We obtain our structures depositing metals using template assisted electrodeposition. We can vary the diameter, length and material (Au, Ni, Fe...) of our NWs. We can also produce core/shell metallic NWs using pulsed electrodeposition, choosing the material of both, the core and shell. As example, we present Ni/Au core/shell electrodes, in which the Ni of the core conferees robustness to the NWs, and the Au of the shell ensures a high electrical conductivity and good biocompatibility. The positive results of the biocompatibility studies support the potential and viability of our electrodes as functional electrical stimulating devices. This project has received funding from the EU Horizon 2020 R&I programme under grant agreement 737116.

Resume : Among the single-molecule detection methods proposed so far, only a few are exploitable for real clinical sensing. Large-area organic-bioelectronics is emerging as a cross-disciplinary research field for the development of a platform capable of selective, label-free and fast biomarker detection at the physical limit in real biofluids. A mass-manufacturable platform with such characteristics holds the potential to bring precision medicine into the everyday medical practice, revolutionizing our current approach to clinical analysis. This lecture aims at critically prioritize the main technologies for single-molecule detection. Scrutinized figures-of-merit include, besides limit-of-detection and selectivity, feasibility of operation in real-fluids, time-to-results and cost-effectiveness. Electrolyte-Gated Field-Effect-Transistors (EG-FETs) [1-4] with a bio-functionalized large-area sensing gate, appear as very promising, also over organic-electrochemical-transistor. The material science and the devices operational aspects underpinning EG-FETs unprecedented sensing performance, including the role of the cooperative hydrogen-bonding network and the gate-channel strong capacitive coupling, are discussed. References 1. Macchia, E., Manoli, K., Holzer, B., Di Franco, C., Ghittorelli, M., Torricelli, F., Alberga, D., Mangiatordi, G.F., Palazzo, G., Scamarcio, G., Torsi, L. Single molecule detection with a millimetre-sized transistor. Nature Communications 9, 3223 (2018). 2. Nature highlights - Selections form the scientific literature. Nature 560, 412 (2018). 3. Macchia, E., Tiwari, A., Manoli, K., Holzer, B., Ditaranto, N., Picca, R.A., Cioffi, N., Di Franco, C., Scamarcio, G., Palazzo, G., Torsi, L. Label-free and selective single-molecule bioelectronic sensing with a millimeter-wide self-assembled monolayer of anti-immunoglobulins. Chemistry of Materials in press (2019) 4. Macchia, E., Manoli, K., Holzer, B., Di Franco, C., Picca, R., Cioffi, N., Scamarcio, G., Palazzo, G., Torsi, L. Selective Single-Molecule Analytical Detection of C-Reactive Protein in Saliva with an Organic Transistor. Analytical and Bioanalytical Chemistry in press (2019).

Resume : This talk will provide an overview of the PIs' efforts to understand the dynamics of biomineralization via in-situ transmission electron microscopy. First we demonstrate how to utilize graphene sheets to build a liquid-cell nanoreactor that fits the chamber of high-resolution TEM. Graphene is impermeable to liquids such as aqueous solutions and therefore can be used to seal liquid solutions from leaking to the high vacuum of TEM environment. In addition, the excellent electrical conductivity of graphene and its ability to scavenge the radicals produced by the interaction of electron beam and liquid solutions provide an excellent platform to perform imaging of biological or hydrated specimens. We then demonstrate our success to observe the biomineralization of hydroxyapatite (HA) crystals. Our results show that HA crystals follow classical and non-classical nucleation theories to from within a supersaturated solution. The solution initially goes through ion-rich and ion-poor liquid-liquid phase separation. Amorphous calcium phosphate (ACP) acts as template for the biomineralization of HA while HA can also form by aggregation of primary HA nanoparticles. We also studied the effect of molecular modifiers on the effect of calcium oxalate crystals that are the primary constituent of kidney stones. We show that the addition of citrate can affect the crystallization pathway of these minerals. Interestingly, the citrate molecules affect the pre-nucleation stage of CaOx crystals making them thermodynamically stable. In addition, the addition of citrate reduces the stability of calcium oxalate monohydrates. In addition, we will showcase some examples of biomineralization of iron oxide core in ferritin proteins and demonstrate the ability to monitor the biomineralization of these crystals using graphene liquid cells in TEM. We will show that the ratio of L and H subunits in the ferritin protein shells can affect the nucleation and growth of iron oxide cores. We also will present our latest results on the biomineralization of magnetosomes in magnetotactic bacteria grown in iron-rich media using in situ GLC-TEM studies. We observed that such bacteria can remain alive and intact during TEM imaging and follows the classical nucleation theory for the biomineralization of magnetosomes.

Resume : Nanohydroxyapatite (nanoHA) are key materials for bone tissue healing, and their functional behavior is ruled in large extent by nature and structure of sites exposed at their surfaces. Relevant challenges are well beyond the recognition of crystallographic facets limiting nanoparticles: for nanoHA the most abundant terminations are just of one type, namely (010), but the atomic structure they expose can be of three types: stoichiometric, Ca-rich and P-rich [1]. These important features are often elusive by direct microscopy imaging, in particular the assessment of their relative amount. Moreover, is there any effect of these different terminations on the causal sequence proposed by Kasemo [2]: atomic surface structure/ surface hydration states/ states of adsorbed proteins/ responses elicited in cells? To contribute to solve this issue, we implemented a synergic loop between preparation of nanoHA in controlled conditions and elucidation of their surface features and interfacial behavior, at molecular level, by combining the experimental study of adsorbed molecules, by in-situ IR spectroscopy, with quantum mechanical modeling of adsorption events, demonstrating the impact of the ratio between (010)_Ca-rich and (010)_P-rich terminations on the structure of adsorbed water multilayers, and on the conformation of an adsorbed protein used as ?probe?, namely bovine serum albumin. [1] R. Astala and M. J. Stott, Phys. Rev. B 78 (2008) 075427 [2] B. Kasemo, Surf. Sci. 500 (2002) 656?677

Resume : In the field of biodevices functionalization, especially for bone implants, active compounds such as ceramics and/or proteins are used for enhancing cellular response. The control on the distribution of ceramic nanoparticles such hydroxyapatite (HA) and Lactoferrin (LF) could significantly influence the cellular response at nano-composites interfaces, as well as the final application towards implants application. Therefore, this work is focused on embedding HA spherical nanoparticles and lactoferrin (LF) within synthetic biodegradable copolymers Poly(ethylene glycol)- block-poly(?-caprolactone) methyl ether (PEG-block-PCL Me) for the preparation of new nanocomposites coatings targeting the modulated response of macrophages and osteoblast cells (i.e adhesion, mineralization). The controlled incorporation of HA and LF within the synthetic copolymeric substrates was performed by matrix assisted pulsed laser evaporation (MAPLE) method using a modular target system. The resulting morphologies and the main features were studied by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Fourier Transform Infrared Spectroscopy (FTIR) data demonstrates that the functional groups in the MAPLE-deposited films remain intact for the individual compounds and that LF was not affected by the solvents used for copolymer. The biofunctionality of the coatings has been tested using the correlated characteristics of the coatings with macrophages and MC3T3- E1 murine osteoblasts response in vitro. The results clearly revealed that the coatings with HA and LF incorporated in the polymeric matrix have enhanced stability as compared with single element coatings, and that the osteoblast behavior (cell adhesion/morphology, proliferation and matrix mineralization) was differentially influenced by the variations in the physicochemical characteristics of materials surface polymeric layers.

Resume : Nanostructured thin films are extensively studied in orthopedics, to overcome the limitations of medical devices and respond to several clinical needs, such as infection and scarce osseointegration. Here, nanostructured antibacterial and biomimetic films are deposited by Ionized Jet Deposition (IJD), by ablation of silver and deproteinized bone apatite targets, respectively. Coating are mainly proposed for metallic implants, but, because IJD deposition can be carried out without heating the substrate, proof-of-concept of deposition onto heat-sensitive porous substrates (polymeric electrospun patches) is shown. Coatings composition (FT-IR, XRD), morphology (SEM, AFM) and adhesion to titanium substrate (micro-scratch test) are tested. Uniformity of coating, maintenance of fibrous morphology and polymer chemistry of the electrospun substrates are investigated by SEM, TEM and FT-IR. All films exhibit a nanostructured morphology and sub-micrometric thickness, and are composed of nanosized globular aggregates. The morphology and dimensions of the aggregates, as well as the deposition rate, strongly depend on the characteristics of the target. Both silver and bone apatite coatings exhibit a composition closely mimicking that of the deposition target and a high adhesion to the substrate. When deposited on electrospun polymers, the films grow around the fibers, without significantly altering their shape and the porosity of the patch or causing significant damage to the substrate.

Resume : Composite thin films of conducting polymer (polyaniline (PANI) grafted Lignin) ? magnetic nanoparticles (Fe3O4) embedded drug (gentamicin sulfate) were deposited by matrix assisted pulsed laser evaporation (MAPLE) technique. Our aim was to obtain the controlled release of the therapeutically active substance, under the action of a magnetic and electric fields for use of these coatings for biomedical applications. It follows that the deposited thin films exhibit a convenient nanostructured surface for bone implants and the unaltered transfer of the initial biomaterials was obtained. The corrosion resistant structures exhibited a significant antibacterial activity against Escherichia coli, Staphylococcus aureus and Candida Albicans strains meanwhile biocompatibility assay (MTT, imunostaining and cellular morphology) demonstrated that the obtained implants are not cytotoxic for bone cells. These results encourage further assessment of this type of biomaterials for their application in controlled drug release at implantation sites by electrical impulse stimulation.

Resume : Jawbone resection is the final surgical treatment for ~5500 patients in EU28 with maxillofacial benign and malignant tumours. The resulting large bone defects lead to scarred, mangled facial appearance and the loss of mastication and speaking function, requiring aesthetic and functional reconstruction as basis for physical and physiologic rehabilitation. Although autologous vascularized bone from fibular or iliac-crest autografts is current gold standard, the portion of transplantable bone is limited and subsequent high-dose anti-cancer chemo-/radiotherapy often results in tissue necrosis. The analysis performed considered the assessment of the impact of 3D printing material on the activation of the genotoxic stress pathway in an in vitro model using human osteoblasts and osteoblast-like cancer cells - SaOS-2. The method of analysis considered micronucleus test and evaluation of the expression of selected genes involved in the genotoxic stress pathway. The expression the determined following genes levels: ATR, MDM2, TP53, PPIA, ATM, CHEK1, CHEK2, CDKN1A. Acknowlegement: This project is implemented under the Program for M-ERA.NET-2016/232/2017 Patient-specific bioactive, antimicrobial PLA-PGA/titanium implants for large jawbone defects after tumour resection ?jawIMPLANT?, funded by the National Centre for Research and Development

Resume : Functionalization of nanocrystals is essential for their practical application to living systems, but synthesis on nanocrystal surfaces is limited by incompatibilities with certain key reagents. The copper-catalyzed azide-alkyne cycloaddition (CuAAC) is among the most useful methods for ligating biomolecules to surfaces, but has been largely useless for semiconductor quantum dots (QDs) because Cu ions quickly and irreversibly quench QD fluorescence. To discover non-quenching synthetic conditions for Cu-catalyzed click reactions on QD surfaces,1 we developed a combinatorial fluorescence assay to screen over 2000 reaction conditions to maximize cycloaddition efficiency while minimizing QD quenching. We identify conditions for complete coupling without significant quenching, which are compatible with common QD polymer surfaces and various azide/alkyne pairs. Based on insight from the combinatorial screen and mechanistic studies of Cu coordination and quenching, we find that superstoichiometric concentrations of Cu can promote full coupling if accompanied by ligands that selectively compete the Cu from the QD surface but allow it to remain catalytically active. Applied to the conjugation of a K channel-specific peptidyl toxin to CdSe/ZnS QDs, we synthesize unquenched QD conjugates and image their specific and voltage-dependent affinity for K channels in live cells. We also report novel covalent protein labeling ligands (i.e., SNAP tags) that are specially optimized for use with inorganic nanocrystals.2 These synthetic hydrophilic benzylguanine ligands (i.e., SNAP tags) allow irreversible conjugation to SNAP tag proteins within live cells ~10-fold more efficiently than existing SNAP tags. This specific and improved protein labeling allows live-cell imaging of kinesin motors and dual-color QD labeling of kinesin heads and to track single protein stepping movement in live cells. 1. V.R. Mann, A.S. Powers, D.C. Tilley, J.T. Sack and B.E. Cohen. Azide-Alkyne Click Conjugation on Quantum Dots by Selective Copper Coordination. ACS Nano 12, 4469-4477 (2018) 2. S.M. Wichner, V.R. Mann, A.S. Powers, M.A. Segal, M. Mir, J.N. Bandaria, M.A. DeWitt, X. Darzacq, A. Yildiz and B.E. Cohen. Covalent Protein Labeling and Improved Single Molecule Optical Properties of Aqueous CdSe/CdS Quantum Dots. ACS Nano 11, 6773?6781 (2017)

Resume : Introduction: Diabetes is a critical medical challenge affecting all of the world. The insulin injection according to the glucose level is a key issue for the treatment of type 1 and advanced type 2 diabetes. In this study, based on gold nanoclusters (GNCs) and MEMS microneedle patches, we aim to develop a smart insulin releasing system responding to the surrounding glucose levels. Method: We used GNCs as a novel carrier due to their high loading capacity of drugs (1). We decorated the GNCs with phenylboronic acid molecules, which serve as key switch factor for glucose-responsive insulin release. Moreover, using MEMS technology, we developed a microneedle patch containing the above GNCs for skin penetration and responsive drug release in vivo. Results: We are able to develop glucose-responsive insulin releasing GNCs, with strong sensitivity to glucose concentrations. Moreover, MEMS microneedle patches enabled the painless puncture of skins and the in vivo drug release. In both in vitro glucose solution and in type 1 diabetic mice in vivo, our system effectively released insulin according to the glucose concentrations, and can regulate the blood glucose in normoglycemic range for up to 3 days. Conclusion: This painless and responsive system can help the diagnosis and treatment of diabetes. Keywords: gold nanoclusters; microneedle patch; glucose control; drug delivery. References (1). Yifeng Lei, et al. Gold nanoclusters-assisted delivery of NGF siRNA for effective treatment of pancreatic cancer. Nature Communications. 2017; 8:15130.

Resume : Metal nanoparticle clusters are regarded as metamaterials, and dispersions of nanoparticle clusters are regarded as metafluids. Surface-enhanced Raman scattering (SERS) from molecules adsorbed on the nanoparticle clusters is one of a notable property of metafluids. SERS is expected to permit the realization of single-molecule detection in chemical and biological samples, especially cells and tissues. However, the most of SERS measurements have been done on substrates, local information of cells and tissues have been hard to obtain. In order to measure the local information of cells, using SERS active particles is one of the answers. To analyze biological samples using SERS, the SERS substrate should be excitable in the near-infrared (NIR) region to ensure high transparency in biological tissues. Furthermore, transporting the SERS particles to the desired position is crucial for obtaining high resolution. In this report, gold nanoparticle clusters based on polymer core?shell particles incorporating magnetic Fe3O4 nanoparticles were prepared via a self-assembly method. The enhancement factor of the SERS signal was determined by the size of composited gold nanoparticles. Furthermore, the migration direction of the gold nanoparticle cluster composite particles in aqueous media was successfully controlled by the application of an external magnetic field. This technique provides a novel way to analyze in situ distribution of biomolecules in cells and tissues.

Resume : The fabrication of flexible photonic materials with accessible and cost effective techniques has proven to be a difficult task in materials sciences, usually resorting to lithography techniques, opals and colloidal aggregates, greatly limiting the uses and sizes of these structures. New methods and structures for the production of Bragg refractors can be developed by taking examples available in the natural world, in which living organisms take advantage of the natural trade-off between employed resources and functionality to obtained efficient photonic structures that aid in several organic processes. This approach is made possible by the combination of a simple polymer infiltration technique, called melt infiltration, in periodically modulated aluminum oxide templates, producing a 3 dimensional polyethylene nanonetworks with a wide range of tuneable photonic responses. The reported method allows the production of such structures in wide areas, resorting to cheap materials like industrial grade polymers and aluminum alloys. The merging of an easy and scalable method with a 3 dimensional network-like structure offers new opportunities in areas as photonics, sensing, energy and clothing. [1] Resende, P. M. et al, Adv. Optical Mater. 2018, 1800408

Resume : In their native environment cells are constantly exposed to biochemical and biophysical signals that guide and regulate complex biological phenomena. Many of these signals impact on the adhesion properties of cells, which define morphology, cytoskeleton arrangements and cell mechanics. Adhesion signals are far from being static, but change in time and space according to specific programmes. Non-correct display of signals may result in catastrophic events. Yet, our understanding on the effects of the dynamics of signal presentation on cell functions and fates is limited. Here we present our recent developments in the engineering of light-responsive platforms to enable the dynamic presentation of patterns of adhesion signals whose features can be controlled in space and time. Irradiation of azobenzene based substrates can alter surface topography in the time frame of few tens of seconds, allowing formation of submicron features, a scale that interferes with focal adhesion formation. We show the potency of these substrates in stimulating individual cells with topographic patterns over varying lengths and timescales, and how dynamic patterns alter cytoskeleton arrangements and cell mechanics. Development of platforms for dynamic signal display would provide valuable insights into cell-biophysical signal interactions and into mechanotransduction phenomena, paving the way to novel systems that mimic physiologic or pathologic extracellular environments for in vitro cell stimulation.

Resume : The detailed understanding of interfaces in biological systems is essential to achieve controllable bioresponses. Here, we characterized two types of biointerfaces in human cortical bone tissues with osteoporosis using high-resolution microscopy and spectroscopy techniques and proposed novel strategies for improving their biomechanical response. First, the boundary between osteonal and interstitial bone materials known as the cement line (CL) was investigated. It was found that CLs are hypermineralized (tougher) interfaces with varying mineralization levels depending on the osteon age, indicating distinct biomineralization dynamics in CLs and osteons attributed to their different organic compositions. According to finite element modelling, having CLs with higher toughness deflect microcracks, thus preventing extensive bone fracture. Second, the interfacial interaction between osteocyte cells and surrounding bone tissue was studied. Highly mineralized plugs explained by a unique biomineralization mechanism following osteocytes death were found. These occlusions can locally alter cellular communication and bone homeostasis, thus decreasing bone fracture resistance. Future medication has to focus on preserving osteocytes, also because they can inhibit mineralization resulting in an empty pericellular space crucial for the fluid flow between cells. Based on these results, smart bioinspired implant materials can be developed to ensure bone stability in elderly individuals.

Resume : Stem cell culture is of paramount importance in tissue engineering and regenerative medicine. Neural stem cells or mesenchymal stem cells therapies have the potential to treat neurodegenerative diseases, either by replenishing the cell pool or through the secretion of paracrine factors. In order to successful apply these therapies, we need to develop appropriate scaffolds that, by mimicking the extracellular matrix to culture cells in vitro and control their fate, offers the prospects to turn these in vitro studies into efficient medical processes. We have been studying the use of conjugated polymers substrates for neural stem cells cultivation and/or differentiation using patterned devices [1]. In addition to the thin film-based scaffolds, the use of polymeric fibers, prepared by electrospinning, based on various polymers, including blends with conjugated polymers, is also being explored. In this communication we report on our progress in the search for polymer based films and fibers scaffolds, including the use of conductive polymers as these offer the possibility to use electrical stimuli, and their ability to sustain viable cell culture. We acknowledge FCT financial support under the projects NEURON (PTDC/CTM?CTM/30237/2017) and UID/EEA/50008/2013. [1] F. Pires, Q. Ferreira, C. A. V. Rodrigues, J. Morgado, F. C. Ferreira, Biochimica et Biophysica Acta General Subjects, 1850, 1158-1168 (2015).

Resume : Cells sense their environment by transducing mechanical stimuli into biochemical signals. Commonly used tools to study cell mechanosensing provide limited spatial and force resolution. Here, a novel nanowire?based platform for monitoring cell forces is reported. Nanowires are functionalized with ligands for cell immunoreceptors, and they are used to explore the mechanosensitivity of natural killer (NK) cells. In particular, it is found that NK cells apply centripetal forces to nanowires, and that the nanowires stimulate cell contraction. Based on the nanowire deformation, it is calculated that cells apply forces of down to 10 pN, which is the smallest value demonstrated so far by microstructured platforms for cell spreading. Furthermore, the roles of: i) nanowire topography and ii) activating ligands in the cell immune function are studied and it is found that only their combination produces enhanced population of activated NK cells. Thus, a mechanosensing mechanism of NK cells is proposed, by which they integrate biochemical and mechanical stimuli into a decision?making machinery analogous to the AND logic gate, whose output is the immune activation. This work reveals unprecedented mechanical aspects of NK cell immune function and introduces an innovative nanomaterial for studying cellular mechanics with unparalleled spatial and mechanical resolution.

Resume : Controlled extracellular chemical and topographical cues can generate physicochemical changes that influence the proliferation and differentiation of neural cells; external electrical stimulation (ES) via conductive bioelectrodes can promote neural differentiation by increasing neurite outgrowth. Because rat pheochromocytoma (PC12) cells tend to differentiate into neuron-like cells upon treatment with nerve growth factor (NGF), we used PC12 as a model to explore the possibility of using a well-designed poly(ethylene oxide) (PEO)/poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) blend solution to fabricate functional bioelectrodes presenting biological fouling/antifouling surfaces, thereby regulating the cell adhesion, proliferation, and differentiation properties. In this study, we found that a flat PEO/PEDOT:PSS composite film, fabricated through spin-coating, operated through a contact repulsion mechanism that limited cell attachment and proliferation; in contrast, the aligned and random PEDOT:PSS nanofibers fabricated through electrospinning promoted neuron adhesion efficiently and allowed manipulation of the cell morphology. Furthermore, we performed ES of PC12 cells to investigate the influence of the conductive random and aligned PEO/PEDOT:PSS composite nanofiber mats on the enhancement of neurite outgrowth, as well as the relative gene expression of Nestin, Tuj1, and MAP2. The PC12 cells on the aligned topography displayed predominantly bipolar neurites along the direction of the nanofibers; PC12 cells on the random nanofibers produced a greater number of neurites than did those on the aligned nanofibers; the neurite length and neuronal gene expression level were enhanced by greater than 60% relative to those of control tissue culture polystyrene plate (TCPS) substrates under ES. Therefore, combining this unique PEDOT:PSS blend solution with various fabrication processes appears to be a facile approach toward bioelectronic interface coatings displaying tunable surface properties for manipulating the cellular behavior of neurons during ES.

Resume : Nanostructured surfaces are called “promising” to control bacterial adhesion and biofilm formation. Initial adhesion is followed by emergence of surface-programmed bacterial properties and biofilm growth. A distinction between nanostructured surfaces can be made based on periodic- or random-occurrence of features, although often nanostructured surfaces are microstructured due to merging of their nanofeatures. Characterization of such surfaces is not trivial due to the myriad of different nanoscaled morphologies. Both superhydrophobic and hydrophilic, nanostructured surfaces generally yield low bacterial adhesion. On smooth surfaces, bacteria deform when adhering, causing membrane surface tension changes and responses yielding emergent properties. Adhesion to nanostructured surfaces, causes multiple cell wall deformation sites when adhering in valleys, while for hill-top adhesion, highly localized cell wall deformation occurs. Accordingly, adhesion to nanostructured surfaces yields emergent responses ranging from pressure-induced EPS production to cell wall rupture and death. Other promising features are increased antibiotic housing, thermal effects and photo-induced ROS production, but the latter two promises are based on properties of suspended nanoparticles and may not hold in nanostructured coatings or materials. To bring nanostructured coatings and materials to application, experiments are needed that go beyond the current limit of the laboratory bench.

Resume : In nature bacteria generally exist as biofilms. Biofilms are a dynamic and structurally complex community of microorganisms embedded in a self-produced matrix of extracellular polymeric substances (EPS). One possible approach to eradicate unwanted biofilms is to use smart responsive technologies that are activated by an environmental cue. Due to bacterial metabolism, cells embedded in the biofilm create a localized acidic microenvironment which is unaffected by the external pH. Therefore, pH monitoring is a promising approach for understanding the complexities of biofilms with potential applications in diagnostics; however, pH measurement is not a trivial task in a 3D and highly heterogeneous system such as a biofilm. A nanoscale pH-responsive sensor would enable in-situ analysis of pH gradient inside biofilms, without altering its natural structure. Based on this, a pH sensor was designed by synthesising mesoporous silica nanoparticles (47±4 nm diameter) conjugated to a pH-sensitive dye (fluorescein-F) and a pH insensitive dye (rhodamine-R) as an internal standard. The fluorescence intensity (IF) drops drastically when the pH is decreased from 8 to 3.5, the fluorescence intensity (IR) was approximately constant. The ratio IF/IR is a sigmoidal curve with respect to the pH, with a working pH range between 4 and 7. The synthesised pH-responsive particles allowed for an accurate measurement of the extracellular pH inside the biofilm matrix, and through confocal microscopy, the biofilm pH can be mapped.

Resume : In biological fluids, proteins are adsorbed onto the surface of nanoparticles (NPs) to form a coating known as protein corona. Most of the corona proteins act as opsonin which activates the macrophage from immune system to uptake NPs, leading to the rapid removal of NPs1). This restricts the development of nanomedicine. Although conjugation with linear polyethylene glycol (PEG) is the standard approach to reduce protein attachment and to avoid non-specific uptake, it cannot fully prevent the opsonization. On the other hand, we have demonstrated polyglycerol (PG) as a promising alternative to PEG, because PG enhanced the aqueous dispersibility and gave stealth effect to NPs2). In order to understand the role of PG, we compare protein affinity and stealth effect of PG and PEG grafted nanodiamond (ND-PG and ND-PEG, respectively) with different density in this paper. Protein analyses by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) indicated that PG was much more resistant than PEG to adsorption of the opsonin proteins such as IgG and complement protein. In particular, there was almost no protein on the dense PG layer. In vitro stealth effect was revealed by TEM; almost no ND-PG was observed in the TEM images of U937 macrophage, while there was ND-PEG in the macrophage. This indicates that PG has much better stealth effect than PEG. In vivo stealth effects including blood circulation and biodistribution will be reported in due course. References: 1) S. Schöttler et al., Nat. Nanotechnol., 2016; 2) L. Zhao, N. Komatsu et al., Angew. Chem. Int. Ed. 2011

Resume : Nano-particles can be used as drug delivery systems to target drug action on specific organs of the body, hence reduce dosage and side effects. One example is the co-functionalization of gold nano-particles (AuNP) with PEG to enhance dispersion and with peptides, to increase cellular uptake [1]. Yet, it is difficult to optimize both functions simultaneously. Varying the PEG end-groups, two methods have been considered, often termed the mixed monolayer and linker (i.e. head-to-tail) approaches, although in both cases, the precise arrangements of the grafted PEG and peptide ligands on the AuNP surface remain unknown. This issue is examined here principally using AFM microscopy. Firstly, AuNP were functionalized separately with PEG and peptide ligands to gauge the affinity of the ligands to the gold nanoparticles. Ligand adsorption experiments were also conducted on gold films, which have shown to be good model systems for AuNP [2-6]. AFM microscopy of the AuNP shows that the ligands improve dispersion and modify the tip/surface adhesion behaviour on the nanoparticles. For the gold films, macro-level sessile drop measurements indicate that PEG and peptide ligands exhibit similar affinity to the gold surface. However, at the nano-level, AFM experiments show differences in the morphology, continuity, thickness and cohesion of adsorbed ligand films. Differences in tip/surface adhesion in water are also measured. Preliminary experiments on co-functionalization using the mixed monolayer and linker approaches indicate differences in AuNP diameters for the two methods. Overall, this study demonstrates that AFM microscopy is a useful tool for investigating the interaction between biological ligands and AuNP. 1. Harrison E. et al, Nanomedicine 11(7): 851-865, 2016 2. Fenter P. et al, J. Chem. Phys. 106.4: 1600-1608 (1997 3. Luedtke, WD et al, J. Phys. Chem. 100.32: 13323-13329 (1996) 4. Pradeep, T. et al, Pure Appl. Chem. 74.9: 1593-1607 (2002) 5. Vericat, C. et al. J. Phys: Cond. Matter 20:18, (2008) 6. Wang, Z. L. et al, Surf. Sci. 440.1: 809-814, (1999)

Resume : Nanoparticles (NPs) have been shown to possess antibacterial properties and are considered a promising tool for biofilm control. Many studies indicate that NPs mainly interfere with the bacterial metabolism and cellular membranes; however fundamental understanding is still lacking on the exact mechanisms involved in these actions, namely with regards to the role of the biofilm self-produced extracellular polymeric matrix (EPS). This work deals with the use of engineered silica NPs to elucidate the role of the EPS in NPs-biofilm interactions, with a main focus on how NPs features (charge, size and hydrophobicity) combine with those of the EPS (composition, density and structure) to determine NPs transport, uptake and accumulation within the biofilm. Engineered fluorescent silica NPs were prepared and their surface functionalised to tailor charge and hydrophobicity (modification with epoxide and amine groups, PEG, benzoic acid and alkyl silanes). Biofilms grown from two Pseudomonas strains were exposed to the NPs and their interaction with the EPS was assessed through confocal microscopy, UV-Vis, IR and fluorescent spectroscopy, dynamic light scattering, Z-potential analysis. Significant differences are observed in uptake and distribution as a function of NP charge and surface groups, suggesting selective NP-EPS components interactions. The outcome of this study will be useful in applications where antibiofouling technology is needed (eg. water, food and biomedical industries).

Resume : Bacteria attachment and growth on implants can cause serious problems and even death to patient. Most materials have been using for bone implants are metallic ones which will be remained in the body for whole life and if it will be infected by any reason, it should be removed immediately. Therefore, scientists have been focused on more natural and biodegradable materials and silk can be a prominent one because of its unique properties like excellent strength, biodegradability and biocompatibility. A new strategy to kill and prevent bacteria from adherence to the implant is introducing nano topography on the surface of implant because the stress at the contact area of bacteria cell wall will be increased significantly. By introducing nano topography to the surface of materials usually the water contact angle has been increased and the surface becomes superhydrophobic. Superhydrophobicity can help to reduce bacteria attachment but at the same time cell proliferation is also prevented. To achieve a good combination of antifouling and cell proliferation, hydrophilic nanopatterned silk-based material is fabricated by oxygen plasma etching method. The fabricated cones height are about 400 nm and center-to-center distance between two cones are about 300 nm. Bacteria culturing experiments showed more than 90% reduction in attachment of bacteria (both S.aureus and E.coli) to the surface while the water contact angle after plasma treatment is about less than 20 degree.

Resume : Changes in the pH of biological systems are crucial to maintain their properties. In microbial fuel cells (MFCs), anode respiring bacteria like Geobacter sulfurreducens can form biofilms that are able to oxidize organic matter to CO2 while transfer electrons to electrode. Conversely, protons are also produced and released to the medium leading to the biofilm acidification. This changes on local pH usually leads to alterations on the bioenergetics process of microbial communities and hence on MFCs’ performances. It is therefore interesting to measure the interfacial pH and its evolution during or after biofilm metabolism of organic substrates. Covalent grafted quinones like catechols can be used as probes to measure and evaluate the interfacial pH during biofilm formation onto carbon electrodes. For monitoring pH variations induce by ionophores in subcellular scale, 5-aminosalicylic acid (5ASA) has been used to form redox active film onto glassy carbon electrode surface through recurrent cyclic voltammetry. The variation of the apparent standard potential of the 5ASA-based film as a function of pH is linear over the entire studied pH range (pH 2 to 10) with a slope of -79 mV per pH unit. Upon deposition of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) onto the modified electrode, ionophores such as valinomycin and nigericin were incorporated into the lipid deposit in order to probe pH at the modified electrode/lipid deposit interface.

Resume : Optical Photothermal Infrared (O-PTIR) is an emerging IR spectroscopy technique requiring no contact with the sample (Figure 1) and providing for highly spatially resolved infrared hyperspectral images down to the 500 nm level. Recent advances have also now made possible the simultaneous measurement of position co-registered Raman spectra - IRaman. This range of spatial resolution is especially suited for the analysis of practically important industrial multicomponent and multiphase product samples, including composites and laminates comprising bioplastics (Figure 2). Such systems are expected to exhibit different degrees of mixing and spatial segregation of individual constituents, which in turn strongly affect the end use performance of the material. In this study, hyperspectral IR (O-PTIR) and Raman image data was obtained simultaneously using the mIRage IR microscope, for a bioplastic composite system is subjected to various forms of two-dimensional correlation spectroscopy (2D-COS) analysis to extract pertinent information about compositional distribution and possible molecular level interaction among the constituents. This first-of-a-kind capability, provides for simultaneous IR and Raman spectra from the same spot at the same time with the same spatial resolution, whilst both data channels (IR & Raman) being spatially registered. This approach takes full advantage of spectral complementarity of IR and Raman to provide for a more thorough sample characterisation. Furthermore, by taking advantage of the simultaneous measurement of IR and Raman spectra using mIRage system, it becomes possible to carry out the 2D hetero-spectral correlation of spectral images, providing for new insights, by utilising the full complementarity of IR and Raman data.

Resume : The rapid rise of optogenetics in neuroscience research over the past decade has led to signifcant advancements in animal studies, medical research and disease treatment. Recent efforts have been focused on flexible, wireless powered, miniaturized optogenetic devices. Here, we report a new optogenetic system which consists of wireless controllable drive module and injectable probe. The system can be applied in multiple animal model (e.g., mouse, monkeys and flies) and different fields of neuroscience(e.g., fundamental research on neural circuit, neurotherapeutics for Parkinson’s disease, drepression, anxiety, cognitive disorders and epilepsy). The system adopts bluetooth 4.0 wireless communication protocol, and the device can be controlled remotely by a terminal(e.g., smart phone, tablet or computer) with a distance as far as 50 meters. Besides, frequency and power of light from the μ-LEDs are adjustable as well. In order to obtain movement of measured object, the drive circuit of the device is equipped with built-in motion sensor modules and power management module, they are energized by a rechargeable lithium battery which has 10-hours battery life. In addition to the device mentioned in this article, we are also trying to fabricate a smaller miniature chip-level optogenetic device which is made from semiconductor technologies entirely and has a anticipated size of 16mm2. In the future work, the optimized coil design for reducing the size of the devices, flexible substrate and high-performance light sources which include better monochromaticity and less divergence angle will be taken into account as well.

Resume : Nano porous anodic alumina structures is a widely studied material that is used for corrosion protection of aluminum surfaces or as dielectric material in microelectronics applications. For more than 40 years porous alumina has been the subject of investigations. It exhibits a homogeneous morphology of parallel pores which grow perpendicular to the surface with a narrow distribution of diameters and interpore spacings, the size of which can easily be controlled between 15 and 400 nm. Monodomain porous alumina templates with very high aspect ratios can also be synthesized by using lithographic preparation. The combination of self-assembly and lithography allows the preparation of porous alumina templates with various configurations of pore arrangement that are not accessible by other state-of-the-art methods. Macro porous silicon structures, prepared by an photo-electrochemical process, has also gained interest in research for many applications which have a demand for mechanical and chemical stability as well as a high order of the pores. The pore diameters at SmartMembranes can differ from 800 nm up to 17 µm using lithographic pre-structuring (up to 100 µm possible). The standard deviation of pore diameter and interpore distance is lower than 10 %. Because of the lithographic pre-structuring technique macro porous silicon with its high ordered structure represents an ideal 2-D photonic crystal (PC) exhibiting novel properties for the propagation of infrared light within the pores. Because of the above mentioned unique properties, nano porous alumina and macro porous silicon can be used in a wide range of applications, such as filters, as platforms for muliti-functional sensors (lab-on-the-chip), as antimicrobial structure, and especially as templates for the fabrication of nanometer-scale bio composites, such as nanotubes or nanowires by using polymer melts for biomimetic applications. One of the joint innovative developments at SmartMembranes is the multifunctional biochip sensor based on the macro porous silicon membranes (in collaboration with ANGLE Biosciences Inc.). This flow-through chip is based on a lab diagnostic method for the determination of DNA and protein species. In this case, complex elaboration methods are replaced by substance-selective separations in the pores of the membrane (transition from 2D to 3D structures with defined surface modification of the inner pore walls). The single-use consumable has been designed for routine and focused multiplex analysis for nucleic acids or proteins. The biochip is a disposable device consisting of a 6.5 mm square chip mounted on a plastic tube. The chip is made of porous silicon with > 200.000 micro channels incorporated in that area. A single capture probe site occupies approximately 70 macro pores. This approach facilitates the interaction between target molecules and immobilized probes, resulting in 3 to 4 times faster hybridization of oligonucleotides or protein binding. A highly selective multifunctional biosensor system could be realized by using a electro-sensory measurement technology. Nano porous alumina membranes with higher aspect ratios can also be implemented in flow-through devices, e.g. filtration modules for sterile filtration of liquids and gases or for the separation of viruses with an exact cut-off. They are also used for cultivation of cells due to their good biocompatibility characteristics. Since the membranes are transparent when wet, they are highly suitable for microscopic investigations or to monitor cell-cell-interactions. Novel trend also show the usage of nano porous alumina as flow control for drug delivery systems, where as the fluidics can be exactly calculated due to the high order and precise sizes of the pores offering flow control depending on pore size.

Resume : Metal oxide materials have drawn much attention in the application of biosensors recently. Various metal oxide materials such as indium tin oxide (ITO), zinc oxide (ZnO) and titanium dioxide (TiO2) with different surface strategies have been utilized in the versatile biosensors to improve the detection performance. In this work, thermal vapor deposition was used to deposit Tin-based oxide thin films as biosensor electrodes with different molar ratio and ceramic processing conditions. After preparation, the morphology and the elements ratio of thin films were characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX), respectively. The electrical properties were analyzed by electrochemical impedance spectroscopy (EIS) analysis and Cyclic-Voltammetry (CV) analysis. It is expected the novel tin-based oxide will manifest the potential in the application of biosensors.

Resume : The research on transient technologies for biomedical applications focuses on the development of devices able to disappear in the biological environment after a fixed time, thus cancelling the risks related to surgical retrieval [1]. Despite astonishing progress in the field [2], one of the main issue still to overcome is the short functional lifetime of transient recording/stimulating devices in the body, which is typically a few days. In the perspective of extending their duration, and consequently their possible applications, our strategy is to abandon the silicon-based approach so far implemented and to rely on entirely polymer-based devices. For this purpose, we fabricated probes for neural signal recording based on Polycaprolactone as support and encapsulation and Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) as conductive component. In-vitro electrochemical ageing tests (NaCl, 37 °C) were performed to estimate the devices functionality in an environment similar to the biological one, whereas the materials degradation and the foreign-body response were monitored at different time-points (3, 9 and 12 months) after implantation in mice brains (visual cortex area). Chronic recordings of visually evoked potentials up to several weeks finally demonstrated the in-vivo functional durability of the devices. This work was supported by European Commission (project № 701632). [1] Kang S.-K. et al., Nature 530, 2016; [2] Koo J. et al., Nat. Med. 24, 2018.

Resume : Implantable neurostimulation devices have been attracted considerable attention recently. When a neural probe is implanted in vivo, neural disordered disease can be treated by electrostimulation. Additionally, electrically controlled drug release has been particularly attractive for bioelectronics because the electrical signal is portable and controllable on-demand, without the requirement of large or special equipment. However, protein-based bioactives such as growth factors or antibodies are easily denatured to lose their bioactivity in response to external stimulation. It is challenging to develop a bioelectrode system that permits the electrically responsive release of proteins without damage. In this study, a polyimide-based biocompatible microelectrode array has been treated by a facile co-electrodeposition method to form hybrid film of iridium oxide and plasma protein. We carried out a cyclic voltammetry approach to co-electrodeposit iridium oxide and plasma protein on Au microelectrode array. We characterized and evaluated the hybrid electrolytes and deposited films for bio-electrode applications. We also demonstrated the releasing behavior triggered by an electric field. In addition, the biocompatibility of the hybrid films was also investigated by testing the cell viability.

Resume : Isolation, purification and concentration of nucleic acids such as DNA and RNA are essential skills in various biotechnology. Because the sample pretreatment results can affect the downstream process, effective and fast sample pretreatment technology has been required. Nucleic acid isolation, purification and concentration methods have evolved over the past several decades. A nucleic acid extraction method widely used in the past is a process using a silica membrane or a magnetic bead. Conventional methods are time consuming and results vary depending on the user's proficiency. In addition, extraction of short nucleic acids such as microRNAs by a conventional method has the disadvantage of low efficiency and high cost. Therefore, the need for rapid, efficient and inexpensive isolation, purification and concentration of nucleic acids has increased in technologies such as molecular diagnostics and pathogen detection. There are several issues in the process of isolation, purification and concentration of nucleic acids, one of which is effective cell lysis. There are two ways to disrupt a cell: physical or chemical. Physical methods include bead beating and sonication, and chemical methods include cell lysis using a surfactant. The second is purification. When the ratio of the absorbance of light in the 260nm and 280nm ranges is measured, it is considered a pure nucleic acid when the DNA has a value of 1.8 and the RNA has a value of about 2.0. The third is concentration, which previously required the use of an ultracentrifuge method, such as density gradient separation, which is expensive and time-consuming to concentrate the sample. Here, we demonstrate a technique for selectively separating nucleic acids with high surface charge relative to their mass in an aqueous solution by electrophoresis method using multi-nanopore structure made of widely used conventional semiconductor processes.

Resume : We report usage of porous silicon nanoparticles (PSi NPs) for theranostics, which means simultaneous diagnostics and therapy by the same active agent. Efficient PL properties of PSi NPs allow fluorescent staining of cells in optical bioimaging. We also performed multi-modal visualization of PSi NPs using linear and non-linear optical imaging techniques such as confocal microscopy, Raman and coherent anti-Stokes Raman spectroscopy. PSi NPs penetrated into the living cells via endocytosis mechanism without any substantial toxicity in concentrations up to 0.5 mg/ml, and completely dissolved after two weeks of the incubation, which was revealed by Raman scattering from the nanoparticles inside the cells. At the same time, PSi NPs delivered chemotherapeutical drugs into the cells and also acted as sensitizers of visible and infrared light, ultrasound and radio waves, which resulted in destruction of the cancer cells. This work was supported by the Russian Science Foundation (Grant ? 17-12-01386).

Resume : In this study, ultrasensitive and precise detection of a representative brain hormone, dopamine chased and demonstrated using functional synthesis by polypyrrole nanotubes modified with aptamer. The produced aptasensor was composed of a micropatterned gold electrode on the glass, polypyrrole nanotube with carboxylated , and specific aptamer molecules. The sensor was constructed by sequential deposition of the PPy-COOH nanotubes and aptamer molecules on the electrode. The sensitivity and selectivity of this sensor were monitored using field effect transistor type measurements. In addition, real dopamine released from PC12 and SH-SY5Y cells induced by high concentration potassium ion (K ) stimulus were also analyzed and compared with the data obtained from the sensitivity (1 nM) and selectivity tests. This article can provide the feasibility for practical use of simple and efficient field effect transistor type aptasensor.

Resume : Hierarchical structures can be found throughout multiple examples in the natural world, conferring better properties to biological systems, like the enhanced photonic response in Morpho butterfly wings or the increased adhesion of suction cups in Octopi. In this work we follow a bioinspired approach in order to fabricate a hierarchical nanostructured polymer film resembling the octopus’ suction cups through a simple patterning method. The patterning is based on the combination of porous alumina templates, a well-known self-ordered system that produces an array of hexagonally packed nanopores, and the melt infiltration of a conductive polymer, PEDOT-PSS, yielding a patterned conductive film. A study is presented of the different properties and morphology of these films. [1] Resende, P. M. et al, Adv. Optical Mater. 2018, 1800408 [2] Baik, S. et al, Adv. Sci. 2018, 5, 1800100

Resume : Recently, the direct conversion of the waste CO2 emission as feedstock into valuable chemicals has attracted increasing research interest world widely. A number of approaches such as chemical, electrochemical, photochemical or biological routes have used CO2 as a sustainable carbon resource for the production of chemicals. In our work, a novel hybrid photoelectrochemical cell by using formate dehydrogenase (FDH) as biocatalyst was applied, to convert CO2 into energy-rich compounds. Therefore, it becomes imperative to immobilise FDH onto the surface of cathode with high electron transfer efficiency. In this work, several metallic substrates and carbon-based materials, such as carbon nanotube and graphene coating, were selected as electrodes to immobilise FDH enzyme onto their surfaces. In order to achieve an efficient immobilization, both chemical and physical functionalization were applied to the selected surfaces. A fast antibody-based dot blot method was established to detect the efficiency of the immobilization of the proteins. The activity of the purified enzymes was investigated by measuring the conversion ratio of NADH to NAD+. Preliminary results showed that the attachment of enzymes strongly depends on surface treatment of the electrodes. The immobilization of the enzymes was significantly improved by forming chemical bonding between the enzyme and the carbon-based materials. The electron transport and activity of the enzyme on the electrode surface will be investigated. Acknowledgements This project has received funding from Research Council of Norway (under the NANO2021 programme), project CO2BioPEC (250261).

Resume : Bicontinuous interfacially jammed emulsion gels (?bijels?) and bijels-derived structures may find many applications. But their wide application is hindered by difficulties in bijels fabrication. Bicontinuous bijels-derived structures possess interconnected channels that are favored in tissue engineering applications as the channels can facilitate transportation of nutrients, oxygen and bioactive molecules while providing space for cell proliferation and migration. Thus in this study, a solvent transfer-induced phase separation (STRIPS)-based technique was developed to make bijels-derived hybrid membrane with good biocompatibility. Bijels membranes having hexanediol diacrylate (HDA) and water phases were produced. HDA was then solidified by UV curing. The channel size in membranes after water removal was 20-100um. Membranes were then immersed in Na-alginate solution, taken out and immersed in CaCl2 solution for crosslinking alginate, resulting in bijels-derived hybrid membranes for tissue engineering. In initial biological studies, human dermal fibroblasts and MC 3T3 cells were cultured on bijels-derived porous HDA for up to 28 days. Results by Live/Dead assay and MTT assay revealed high cell viability and good cell proliferation. SEM and confocal microscopy showed both cells migrated and proliferated well in channels of membranes having average channel sizes larger than 50um. In membranes with smaller channel sizes, both cells exhibited only partial migration into channels.

Resume : There is a growing need for biocompatible nanocomposites that will effectively interact with biological tissues through multiple modalities. However, many new synthesised nanomaterials are limited their use in neural tissue engineering application due to higher cytotoxicity. Hence, synthesis of new materials with good biocompatibility and biodegradability is always in demand for tissue engineering applications. we studied various materials such as gold nanoparticles, silver nanoparticles coated substrates to promote neural differentiation and outgrowth. however, it is two dimensional. Various researchers developing the three-dimensional tissue engineering scaffold such as a hydrogel. However, hydrogel has its own disadvantages and limited to the number of hydrogels only available. Hence, three-dimensional nanomaterials are an emerging source for neural tissue engineering application. Here, we synthesise the ZnO tetrapods microstructures with controlling physicochemical properties. The interaction of zinc oxide tetrapods is investigated with neuronal cells. We studied the cell viability and differentiation of PC12 cells and SH-SY5Y cells. Results showed good biocompatibility and excellent interaction with cells. Controlling organization of Zinc oxide tetrapods structures can be a promising material for 3D neural network outgrowth and scaffold for neural tissue engineering. as a Nanotechnology advanced Carbon dots (CDs) could serve as biocompatible fluorescence nanomaterials for targeted tissues/cell imaging. To achieve this goal, the fluorescence as well as the targeting properties of the CDs should be improved. Herein, we synthesized CDs doped with different metals (Au, Ag, Ga, Zn and Sn) and elements (B, N and P) using acoustic cavitation and hydrothermal methods, respectively. The effects of different experimental parameters on the physico-chemical properties such as size and shape were studied. The prepared CDs showed good quantum yield, minimum cytotoxicity and good cellular uptake when interacted with neural cells. Moreover, doping CDs with metals/elements improved neurites' initiation and elongation when compared with pristine carbon dots. Our research demonstrates the use of CDs for imaging and neuronal interactions. The prepared CDs show promise due to their biocompatibility, photo-stability and potential selective affinity, paving the way for multifunctional biomedical applications.

Resume : Dual-converted fluorescent probe is very useful for monitoring hazard materials for the human being. Especially, heavy metal monitoring methods have been developed for several decades, because of the fatal toxicity and the harmness of the heavy metals such as mercury, lead or cadmium to the human health. Through the development of nanomaterials and surface functionalization method, the field of photoluminescence (PL) point-of-care testing was enabled. Especially, the dual imaging for the detection under only one light source was challenge. In this work, we demonstrated the dual-monitoring system using up/down converted PL nanohybrids under a single light source. Using the PL nanohybrids as the probe, the detection of heavy metal was possible. The fluorescent chemical conjugated nanocapsule showed selective and sensitive performance to mercury ion. Moreover, the dispersion of the fluorescent probe was tracked by upconverted light from the core of the nanocapsule. Their application in the real world can be expanded not only drinking water or tap water, but also the ground surface or the living organisms.

Resume : We present results on three dimensional (3D) photonic effects in optically transparent and flexible media like PDMS polymer by using direct laser processing approaches. Short and ultrashort laser pulses generated in the UV-ViS-NIR spectrum are used for producing of optical waveguide arrays or periodically patterned structures. By controlling the laser parameters like wavelength, fluence, pulse duration, number of pulses, direct laser patterning or ablation can be performed in local surface or volume area without limit of the planar structures. The elasticity of PDMS allows tunable control of the structures’ parameters and hence of the photonic effects induced. This method enables non-clean room and easy controllable fabrication approach of photonic elements spanning from skin or implantable wearables for healthcare monitoring to implantable neural interface devices as well as the chip-scaled optical interconnects. Different techniques (UV-Vis spectroscopy, x-ray photoelectron spectroscopy, optical and scanning electron microscopy) are used for study of optical, compositional and structural properties of the pristine and the laser treated areas.

Resume : The advanced study of nanocarbon surface bioactivity allows fundamental investigation and develop biotechnologies for a creation bioactive-compatible materials with smart interfaces due to immobilized surface by nanocarbon coating layer for the bio-activation, protection from virus biomaterials. The direct confirmation of nanocarbon bio-activity is pioneering results at UC of Riverside which demonstrated the topography single bone forming cell on multi-walled carbon nanotubes (MWCNTs) at the interface with hydroxyapatite (Laura Zanello at al., NanoLett., 2006, 6, 562). Also, well known a fundamental investigations carbon surface chemistry and carbon-modified surfaces (carbohydrate coatings) for bio/hemocompatibility of such surfaces (Paula E. Colavita, Trinity College Dublin, Dublin, Ireland). The investigation is aimed to develop a surface bioengineering of nanocarbons by the immobilization of the molecules (fullerenes, carbon nanotubes) in water suspensions for coating formation on biomaterials and to invaluable a bio-behaviour of these new nanomaterials at an interface with biomedical materials ? silicon, titanium, hydroxyapatite. The experimental results for the short MWCNT with high reactivity due to high concentration of end carbon atoms with free bonds and with additionally increased reactivity due to of defect sites on sidewalls in addition to end carbon atoms with free bonds are presented. As a result of the complex optical spectroscopy (UV-visible-NIR, IR- and Photoluminescence Spectroscopes) and imaging investigation (SEM, AFM) of these nanotubes in water suspensions and nanostructures on silicon surface prepared in accordance with developed schemes, we confirm that tubes with sidewall structural defects and immobilizing groups to recognize biomolecules. Then surface biosensing of these nanotubes in a water suspension and on silicon surface, as photoluminescent ones at 450-700 nm, is tested for DNA sequences, biotin, glucose. Also for recognition of these biomolecules was using electrochemical characterization of the short MWCNT layer on silicon surface.

Resume : Flexible and wearable bio-electrode provides a variety of is made from various biocompatible biomaterials that provide safely to achieve a wide range of complexity and functionality. Here, we developed flexible and wearable bio-electrode that could acquire the bio-signals from the skin surface. Multi-layered electrode were encapsulated and used as substrate and its biocompatibility, conductivity, elasticity and acquisition of the electrocardiogram were characterized according to the size of recording site area. The fabricated electrode composes of polyimide and metal layer was fully encapsulated in polydimethylsiloxane which provide flexibility and biocompatibility. To characterize the performance of electrode, three different-sized electrodes were fabricated, and the signal was tested to be enhanced in proportion to the size of the recording site. To ensure electrical safety of fabricated electrode, the leakage current was examined. The developed electrode showed extremely small leakage current compare to direct contact electrode over the range of applied current from 0 to 10 mA. More than 99% of the applied current was prevented from leakage into the surrounding tissues with no inflammation or infection, in contrast to the current leaked from direct-contact electrodes. A flexible and wearable electrode enhanced level of conformal contact with electrical performance by biomimcked environments, bio-signal qualities were successfully achieved. This suggested flexible and wearable electrode may be utilized to monitor several physiological signals without any risks due to the direct metal contact to tissues.

Resume : We report in this work, the synthesis and characterization of a novel immunosensor based a screen-printed gold electrode (SPAuE) modified with a new structure of iron magnetic nanoparticles coated with poly (pyrrole-co-pyrrole-2-carboxylic acid, Py-Py-COOH) (Py/Py-COOH/MNP) particles to increase the immunosensor sensitivity of Tumor Necrosis Factor-? (TNF-?). TNF-? antibodies were covalently bonded to Py/Py-COOH/MNP modified SPEAu. A sandwich-type detection strategy was then employed for antigen (Ag-TNF-?) detection through the labeled conjugate antibody (Ab-TNF-?-HRP) activity in a TMB solution. Finally, the chronoamperometry technique was applied to characterize the modified SPEAu. The use of a conjugate antibody anti-TNF-? labeled with horseradish peroxidase (Ab-TNF-?-HRP) was investigated using tetramethylbenzidine (TMB) substrate as electrochemical substrate. The modified screen-printed gold electrode (SPEAu) was characterized for the first time, using atomic force microscopic (AFM) and scanning electron microscopy (SEM). The specificity of the immune-sensor was then investigated under the optimal experimental conditions by analyzing aqueous solutions containing possible interferences represented by other salivary cytokines secreted in the acute stage of inflammation, such as interleukin-6 (IL-6) and interleukin-10 (IL-10). The developed immune-sensor showed good performances for Ag-TNF-? detection within the range of 1 pg mL-1 to 15 pg mL- 1 of antigen TNF-? was determined at 1 pg mL-1. The present immune-sensor is this very promising for sensitive and rapid detection of antigen Ag-TNF-? in clinical sample.

Resume : To make high-performance bioelectronic devices, a good ohmic contact between the electrode and active layer is required. Ohmic injection based on semiconductor material have been studied, while for the biointerface, since tunnelling phenomena exist, there still need further work to confirm Ohmic injection contribution. Here, we present a new solution processed DNA based hybrid material, and this material demonstrate selectively hole transport property. This new biointerface works well based on diode and transistor structure, demonstrate effectively ohmic injection. Furthermore, we give a detailed information based on experimental results, confirm that Ohmic injection contributes to the device performance. Besides this, the new biointerface demonstrate less surface recombination at collecting contacts. To specify the DNA role, we also done the temperature dependent test (down to 80K). Finally, this biointerface can be used in roll-to-roll technique, enhancing correlated device performance from the large printed flexible device. All these results indicating that this new biointerface works well due to the effective ohmic injection.

Resume : Bioelectrochemical system (BES) is an emerging innovation field that synergistically integrates advanced nanotechnology with biotechnology, exploiting the high selectivity and specificity of enzyme immobilized on the surface. In this study, we propose a novel hybrid catalyst for the electrochemical reduction of CO_2 to formic acid. The FDH from Thiobacillus sp. KNK65MA is immobilized on the cathode using a trees-like nanostructurated mesoporous support of Titanium Nitride (TiN) fabricated by Pulsed Laser Deposition (PLD). Thanks to this technique, we realize a support with high surface area improving the bio-interface. By an enzymatic assay, we demonstrate that nanostructuration increases the surface area of the support and favours enzyme immobilization. The efficiency of the system is investigated at different applied potential, showing that during a 3 h reaction period the electrosynthesis of formic acid is 5.3 ±0.4 ?mol with a Faraday Efficiency of 61% under low potential applied of -0,45 V_RHE. Finally, the physical characterization of the hybrid electrode show that the nanostructure does not undergo any important modifications in its morphology and composition after the test, demonstrating the mechanical stability of the TiN scaffold. To conclude, here we demonstrate that the TsFDH|TiN electrode has a great potential in terms of product specificity, stability and sustainability to develop a technology for CO_2 reduction.

Resume : The detection of circulating tumor cells (CTCs) is very important for cancer diagnosis. CTCs can travel from primary tumors through the circulation to form secondary tumor colonies via bloodstream extravasation. The number of CTCs has been used as an indicator of cancer progress. However, the population of CTCs is very heterogeneous. It is very challenging to identify CTC subpopulations with high metastatic potential, such as cancer stem cells (CSCs), which are very important for cancer diagnostic management. We report a study of real-time CTC and CSC imaging in the bloodstreams of living animals using multi-photon microscopy and antibody conjugated quantum dots. We have developed a cancer model for noninvasive imaging wherein pancreatic cancer cells expressing fluorescent proteins were subcutaneously injected into the earlobes of mice to form solid tumors. When the cancer cells broke from the solid tumor, CTCs with fluorescent proteins in the bloodstream at different stages of development could be monitored noninvasively in real time. The number of CTCs observed in the blood vessels could be correlated to the tumor size in the first month and reached a maximum value of approximately 100 CTCs/min after five weeks of tumor inoculation. To observe CTC subpopulations, conjugated quantum dots were used. It was found that CD24+ CTCs can move along the walls of blood vessels and migrate to peripheral tissues. The accumulation of CD24+ cells on the sides of solid tumors was observed, which may provide valuable insight for designing new drugs to target cancer subpopulations with high metastatic potential. We also demonstrated that our system is capable of imaging a minor population of cancer stem cells, CD133+ CTCs, which are found in 0.7% of pancreatic cancer cells and 1-3% of solid tumors in patients. With the help of quantum dots, circulating tumor cells with higher metastatic potential, such as CD 24+ and CD 133+ CTCs, have been identified in living animals. Using our approach it is possible to investigate detailed metastatic mechanism, such as extravasation of tumor cells to the blood vessels. In addition, the number of observed CTCs in the blood stream could be correlated with the stage of tumor.

Resume : The kidney plays an essential role in the normal body function. Dialysis is a treatment method used to for blood purification in case of kidney failure or reduction of the efficiency of blood filtration, which causes a socio-economic burden on the patient and society in general [1, 2]. In this work we aim developing a new microfluidic device composed of several ?filtration units? that miniaturize the dialysis system. Each ?filtration unit? encapsulates a smart, adaptive Polyacrylamide (PAAM) hydrogel matrix having specific properties. The polyelectrolyte matrix is the functional unit of the device and acts as an exchange membrane. Using hydrogels having different properties will lead the generation of different filtration units each having a specific function and imitating a specific renal activity. In this work, several 2D hydrogel matrices are prepared and their physicochemical properties are tailored as desired in order to monitor the filtration ability and efficiency of the ?filtration unit?. Controlling the pore size of the matrix will allow monitoring the size selectivity or the molecular weight cutoff while controlling the pores number will help controlling the speed of solute diffusion across the matrix. In addition 3D matrices are developed in order to host cells in some units and will work as bioreactors. The future bioartificial kidney would be an assembly of several filtration units working in parallel. 1. Ota, T., et al. IEEE Micro Electro Mechanical Systems (MEMS). 2018. 2. Ising, C. and P.T. Brinkkoetter, Springer International Publishing: Cham. p. 563-575. 2017.

Resume : We report results of investigation of binding of porous silicon nanomaterials, i.e. porous silicon films (PSi) and nanoparticles (PSi NPs) with different types of enveloped viruses such as H1N1 influenza A (Flu), Poliovirus (PV1), Human immunodeficiency virus (HIV), West Nile virus (WNV) and Hepatitis virus (HAV). The interaction of the nanostructures and the virions was confirmed by electronic and optical methods. According to TEM images and dynamic light scattering measurements, the virions were stuck to the porous surface of the nanoparticles, which led to the formation of large agglomerates. Such agglomerates were easily precipitated by centrifugation, and that approach was used to clean the suspensions from the viral contamination. Moreover, the discovered binding was useful for optical sensing of the virions absorbed on the PSi surface. This work was supported by Russian Science Foundation (RSF) grant No. 17-12-01386.

Resume : The titanium carbides, such as Ti3C2, belong to a new family of two-dimensional nano-materials called MXenes and exhibit in addition to many interesting properties also strong biological activity. However, in spite of intensive research of these materials, the physico-chemical mechanisms determining the biological behavior of titanium carbides are rather poorly understood. Partly, it lies in complex technology employed to synthesize these materials and in the formation on titanium oxides on their surfaces. In this communication, we report joined experimental and theoretical studies of these exciting materials that should shed light on the mechanisms leading to the toxicity of Ti3C3 flakes towards cancerous cells. We fabricated the samples, characterized them carefully, and finally performed ab initio calculations to explain the possibility of formation of the Ti-O bonds and further TiO2 layers on the Ti3C2 surface. Our studies reveal that the formation of TiO2 layer influences the biological activity of the samples regardless of the post-growth treatment employed. We conclude that the presence of TiO2 oxidation layer on the surface of 2D Ti3C2 monolayers should not be considered as a disadvantage when specific bio-action of MXene monolayers is required, however, the interference between oxidation and post-treatment effects on cytotoxicity requires very carefully monitored. Acknowledgements: Support of NCN through the grant SONATA (UMO 2017/26/E/ST8/01073) is acknowledged.

Resume : Over the last few decades, significant efforts have been involved to develop rapid, accurate, reproducible and portable diagnostic technologies in science and engineering. Recently, the field-effect transistor (FET) has been used in the development of diagnostic tools. It is gated by changes of charge carrier density in the channel induced by the binding of target molecules, leading to electrical signal. The FET platform is attractive as sensor plaform due to their low cost, easy operation, rapid response, parallel sensing as well as high sensitivity. G-protein-coupled receptors (GPCR) are seven-transmembrane domain receptors, mediate a variety of cellular response. An unique binding event between ligands and receptors causes a conformational change and activate internal transduction, thus resulting in the production of hundreds of second messenger molecules. It has been used as the target for the development of drugs in many clinical indicators. Therefore, the development of a GPCR-conjugated analytical device is highly desired. Herein, we introduced a high performance FET-typed sensor with G-protein-coupled receptor (GPCR) to detect biocide molecules under 100 ng/ml within 100 s. Micro-patterned graphene was used as electrical channel between electrodes for efficient charge carrier transport and integrated with GPCR in the FET system. It exhibited high sensitivity and provided multiple responses toward mixed targets. Moreover, it showed unprecedented reliability and reproducibility in control experiments. It could provide the opportunity a variety of sensor such as disease diagnosis, drug discovery, and food-spoilage in the future.

Resume : Identification of a single point mutation in peptide could aid understanding the effect of biostructural changes on protein behavior such as formation of insoluble amyloids. Established techniques to detect the mutation in peptide is either destructive or requires rigorous molecular labeling. We propose a non-invasive and label-free detection method of amino acid (AA) substitution in primary peptide fragments, relying on the analogy between vibrational Raman scattering signal of the amino acids and the peptide. The identification process converts surface-enhanced Raman scattering (SERS) signal of 20 proteinogenic amino acid into a spectral library of representative barcodes and quantifies the correlation between their encoded spectral features with that of peptide fragment. We discover that the specificity of the barcode system was improved when extending the screening region to include high frequency vibrations (2500-3500 cm-1). Coupling with the sensitivity of the designed shell-isolated SERS sensor, the barcoded system can identify amino acids in 15-20 amyloid β peptide and detect single point mutation of Lys28 in the Aβ (25–35) peptide with a detection limit of 10(-5) M.

Resume : To meet the needs of the bio-electronic interfacing for the neuronal network and physiological signal transmission applications, highly sensitive and miniaturized electronic elements for the detection of sodium/potassium ions have been of interest. A nanoscale BioFETs composed of the nanowire (NW) have received great attention in the past decades due to their promising applications of biological/chemical sensors、ion-sensitive sensors and nano-bioelectronics. In this NW bioFET system, ions in aqueous solutions can play an important role in determining the surface potential at the liquid-NW interface, accordingly affecting the fundamental electrical characteristics of NW bioFET systems. In this report, we fabricated the p-type NW bioFETs using CMOS-compatible manufacture techniques for exploring the possibility of using NW bioFET as potassium ion-sensitive electronic device for bio-electronic interfacing applications. The sizes of the NW of 77 and 210 nanometers in our silicon NW bioFETs were defined by using the electron-beam lithography technique. Both the back-gate and liquid-gate control modes were adopted for studying the effect of the gate capacitive coupling on the ion-sensitive behaviors in the NW bioFETs. We found that when the NW bioFETs were operated with the back-gate mode, the value of the threshold voltage shift, corresponding to the potassium concentration change, for the 210-nm NW BioFETs was greater than the voltage shift for the 77-nm NW BioFETs. While, under the operation of liquid-gate mode, the 210-nm NW bioFETs showed a smaller voltage shift than that of the 77-nm case. This report provides information about the importance of the gate control mode on the ion-sensitive characteristics of NW bioFETs for bio-electronic interfacing applications.

Resume : The market of non-invasive glucose sensors is drastically growing due to increasing number of people suffering from diabetes. Therefore, there is a significant need for any improvement in the field of biosensors that can be used for monitoring of glucose level in human body. In recent times, the emphasis is put onto the modification of electrode material with enzymes possessing recognition center specific toward particular molecules. In this work, the nanoscale Ti-Au heterostructure functionalized with glucose oxidase (GOx) is reported. Ti-Au material was prepared by anodization of Ti foil, chemical etching, thin Au layer sputtering and finally thermal treatment under continuous regime. The formation of single Au nanoparticles per each structure dimple was revealed by SEM and AFM inspection. In order to confirm enzyme presence and to describe the chemical state of the elements, XPS measurements were performed indicating the complete coverage of Ti-Au material by GOx layer. The obtained electrodes were tested in 0.1 M PBS with an addition of glucose using cyclic and differential pulse voltammetries. The determined linear range, detection limit and sensitivity of tested electrodes satisfy the demands for glucose detection in human body fluids. It was also found that the prepared material is highly reproducible which is of key importance for sensor fabrication. This work was financed by National Center for Research and Development under grant no LIDER/2/0003/L-8/16/NCBR/2017.

Resume : In recent years, IR-IR upconversion nanoparticles (UCNPs) have shown a great interest in nanomedicine, essentially in medical imaging, due to their ability as imaging agents in the optical window of biological tissues. In this context, NaYF4-based core-shell UCNPs co-doped with Yb3+ and Tm3+ ions were designed to result in 800 nm emission upon excitation at 980 nm. The thermolysis synthesis of those UCNPs was performed one-pot in a mixture of octadecene and oleic acid at high temperature (? 300°C). After purification, samples were characterized structurally (XRD), morphologically (TEM), and their emission spectra were recorded upon 980 nm excitation. DLS measurements were also carried out to determine the UCNPs size, indicating a mean hydrodynamic diameter of 46 nm in accordance with TEM results. The main aim of this work was devoted to the development of multimodal UCNPs for targeting prostate cancer cells by fluorescence imaging and scintigraphy. Thus, radio-labelled hydrophilic UCNPs were prepared by a multi-step process. Firstly, several phosphate-based polyethylene glycol (PEG) ligands were synthesized and exchange method was used to make UCNPs water-soluble. PEGs used for ligand exchange include azide group to conjugate both PSMA targeting ligand and radiolabelled prosthetic group to the UCNPs by bio-orthogonal chemistry. Competition binding assays in LnCAP cell lines showed a good affinity of PSMA ligands toward their target. Finally, synthesis of fully functionalized UCNPs are ongoing. They will be tested in vitro and in vivo against PSMA-expressing prostate cancer cells/tumours to assess the efficiency of active targeting and their optical/scintigraphic imaging properties.

Resume : The natural molecules of secondary metabolism produced by plants often have interesting pharmaceutical or cosmetic properties. The structure of these molecules is very complex, making their chemical synthesis almost impossible. To overcome this problem, one solution is to produce the enzymes responsible for their synthesis in plants and to use them in vitro to synthesize the molecules of interest from commercially available precursors. In plants, cytochromes P450 are described as being responsible for the synthesis of a large number of molecules of secondary metabolism. These enzymes are membrane monooxygenases which must be associated with NADPH P450 reductases. This reaction requires the presence of the NADPH cofactor, which is then a limiting and relatively expensive element. The goal of this work is to implement an electrochemical device allowing the use of cytochromes P450 to biosynthesize molecules of interest. For that, we have explored the covalent immobilization of a rhodium complex mediator ([Cp*Rh(bpy)Cl] ) on the surface of porous electrodes for NADPH regeneration. In this communication, we want to highlight the different strategies that we have studied, including diazonium electrografting, click-chemistry and metal complexation [1-3]. [1] L. Zhang et al., ChemElectroChem. 5 (2018) 2208–2217. [2] L. Zhang et al., ChemCatChem. 10 (2018) 4067–4073. [3] L. Zhang et al., ACS Catal. 7 (2017) 4386–4394. This work was supported by the French PIA project « Lorraine Université d’Excellence », reference ANR-15-IDEX-04-LUE.

Resume : Semiconducting polymers are very promising materials for biomedical application, thanks to their ability to conduct both ions and electrons, their biocompatibility and their flexible and soft mechanical properties. In particular, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has high conductivity, electrochemical and thermal stability in aqueous environment and reversable electrochemical properties that render it suitable as smart nano-biointerface with biological elements and environment. In our work, we present PEDOT:PSS-based Organic Electrochemical Transistors (OECTs) for the electrical continuous monitoring of CaCo-2 and NIH-3T3 viability and their reaction to exogenous toxic agents, providing an easy, fast and real-time way overcoming standard optical evaluation techniques. Cells are directly grown on thin PEDOT:PSS thin film OECTs: the presence of a cell monolayer slows down ions flowing from the electrolyte in the semiconducting polymer, thus giving an electronic readout of cell layer integrity and health. Noteworthy, a suitable pattern of the dimensions of devices allows the study of different kind of cells, even leaky-barrier or non-barrier cell lines commonly not suitable for electrical monitoring. We demonstrated that our PEDOT:PSS OECTs provide a simple, low-cost and dynamic biosensors able to monitor leaky-barrier cell culture growth and stress response induced by drug treatments, paving the way for high throughput and low-cost screening of drug discovery or toxicology.

Resume : The advantages of porous silicon nanoparticles (PSi NPs) are associated with their low cytotoxicity and good biodegradability in physiological fluids and in living tissues. In this study such informative optical methods as Raman micro-spectroscopy and photoluminescence spectroscopy as well as confocal microscopy were employed for diagnostics of biodegradation of PSi NPs in simulated suspensions and living cells. We used 100 nm nanoparticles with pore diameters of 15±5 nm and specific surface area of 230 m2/g. PSi NPs have been found to have stable structural and optical properties for at least 6 months when stored in water at high concentrations. However, when incubated with cells or when introduced into model biological solutions, the nanoparticles began to dissolve. The PSi NP dissolution processes were studied by changes in their Raman spectra, where a low-frequency shift of the signal maximum, its broadening and a decrease in intensity are observed. Also during the process of dissolving of PSi NPs, their photoluminescence first flared up and then dramatically dropped, which was also noticeable when visualizing nanoparticles in living cells. The reason for this is the decrease in the size of silicon nanocrystals, in which phonon and quantum confinement effects occur. This work was supported by Russian Science Foundation (RSF) grant No. 17-12-01386. UAN also acknowledges the scholarship of the Foundation for Development of Theoretical Physics and Mathematics "BASIS".

Resume : We report on highly sensitive optical detection of bacteria via efficient adhesion on the surface of new nanostructurized material called double etched porous silicon (DEPSi). DEPSi was obtained by two-stage etching process, i.e. 1) electrochemical etching of monocrystalline Si wafers in hydrofluoric acid solutions, which resulted in formation of mesoporous silicon layer (pore diameter was about 5-15 nm), and 2) metal-assisted chemical etching (MACE) of the porous layers, which created bigger pores or holes with diameter in the range of 100-1000 nm. DEPSi was demonstrated to be a good compromise between perfectly flat structures required for efficient optical detection and rough surfaces with high affinity to bacteria. The surface of the DEPSi had a lot of cavities and holes, which acted like traps for bacteria. Detection of bacteria (E. Coli) was performed by two optical methods, i.e. infrared spectroscopy and interferometry. The first approach revealed chemical bonds (C=C) typical for the bacteria on the surface of DEPSi. The second one used the DEPSi layer as a Fabry-Perot interferometer. In the presence of the bacteria, interferograms were changed, and Fast Fourier transform analysis of the reflectance spectra showed reversible broadening and shift. This allowed detection of the bacteria with sensitivity higher than 10 000 colony-forming units per mL. This work was supported by the Russian Science Foundation (RSF) grant No. 17-12-01386.

Resume : Carbon nano-onions (CNOs) are a class of promising carbon nanomaterials for biomedical applications. Functionalized CNOs show high cellular uptake and low cytotoxicity and fluorescently labeled CNOs (f-CNOs) are excellent platforms for biological imaging. Although CNOs present promising toxicity profiles, evaluations in complex models are required to corroborate biosafety concerns. Zebrafish (Danio Rerio) present numerous peculiarities in comparison to other vertebrates, enabling fast assessments of nanomaterial toxicity [1]. CNOs are more biocompatible in comparison to other carbon nanomaterials, including carbon nano-horns, nano diamonds and graphene oxide [2]. In this study, the biological interactions of f-CNOs in zebrafish during the development are investigated in terms of biosafety assessment and biodistribution [3]. Different toxicological endpoints are evaluated in embryos/larvae treated with f-CNO, including swimming and cardiac activities. Moreover, the biodistribution of f-CNOs is determined at different stages of growth, using advanced fluorescent microscopy techniques. Our results reported the biosafety of f-CNOs and their specific biodistribution in zebrafish. References [1] M. d?Amora, S. Giordani, Frontiers in Neuroscience, 2018, 12, 976. [2] M. d?Amora, A. Camisasca, S. Lettieri, S. Giordani, Nanomaterials, 2017, 7(12), 414. [3] M. d'Amora, M. Rodio, G. Sancataldo, R. Brescia, F. Cella Zanacchi, A. Diaspro, S Giordani, Scientific Reports, 2016, 6, 33923.

Resume : We prepared porous silicon nanoparticles (PSiNPs) with amphiphilic properties, i.e. outer surface of PSiNPs was hydrophilic in order to provide good biocompatibility of the particles, while inner surface was hydrophobic. Initial mesoporous silicon layers were coated by hydrophobic octadecylsilane (ODS), then they were fractured to 200-nm PSiNPs in a mixture of ethanol and water in a planetary ball mill. This procedure also created a hydrophilic surface. Hydrophobic surface inside PSiNPs amplifies cavitation under ultrasonic activation, which resulted in a twofold decrease of cavitation threshold at frequency of 2.08 MHz. Experiments in vitro revealed 20% decrease of ultrasonic intensity threshold for cells viability in the presence of 0.5 mg/ml of PSiNPs. This can be used for the selective ultrasonic treatment of cancer tumors after targeting of PSiNPs. Near-infrared photoluminescence of PSiNPs (quantum yield was about 5%) was activated by sodium tetraborate treatment before ODS functionalization. Efficient luminescence provided visualization of PSiNPs in living cells. Thus PSiNPs are promising agents for theranostic applications. This work was supported by the Russian Science Foundation Grant N 17-72-10200.

Resume : The swimmer here is chiral in nature. A chiral squirmer can rotate while translate in the fluid medium. This is an advantage for the body as it can adjust its direction of motion by adjusting its rotational motion while sensing an external chemical stimulus. Here we have considered an unsteady chiral squirmer which performs a periodic motion in the fluid medium. This has been modelled with a time-dependent active slip velocity on the surface. In the presence of a chemical stimulus the system responds to it by an adaptation and relaxation mechanism. The body eventually alters its time-dependent restricted motion through the modification of the coefficients of the slip velocity after sensing the stimulus. We study how the sensing of the stimulus depends on the strength of the gradient and frequency of oscillation of the body. This study is useful in designing artificial swimmer which is able to chemotax.

Resume : Scientific efforts are nowadays focused on the reduction of pollution levels in the atmosphere through harnessing and effective exploitation of renewable and sustainable energy resources. Fuel cells offer a unique combination of benefits that make them a vital technology ideally suited to replace/serve important segments of our energy infrastructures due to their high-efficiency conversion of chemical energy to electricity with low environmental impact. An innovative class of fuel cells, called Microbial fuel cells (MFCs) leverages the ability of bacteria to produce electricity via the digestion of organic matter such as domestic wastewater as fuel. However the performance of MFCs remains modest for practical applications. In this presentation we discuss work towards improving MFC performance via tailored interfacial interactions. Improved adhesion of biofilms to the electrodes is expected to enhance MFC power outputs. Modification of anode materials with biomolecule derivatives of aryldiazonium salts is investigated as a means of modulating biofilm adhesion. Electrografting of in situ generated cations on graphite anodes was found to result in changes on the rate of biofilm development, thus affecting the polarisation/power density output. The role of wetting and biorecognition on biofilm development was investigated via screening of biomolecule derivatives.

Resume : It is necessary to develop interfacing compounds for immobilizing the bioprobes, including an antibody, aptamer, natural receptors and so on, on the platform of biosensors which are consisted of 2D nanostructure. There are various 2D nanomaterials in the literatures. In particular, a graphene has high-conductivity, so the graphene-integrated biosensors have been constructed to enhance their sensitivity and selectivity. However, the surface of the graphene is highly stable owing to their non-covalent electron pairs, so that their surface modification is challenge. In this study, we demonstrated a new technology for graphene interfacing technologies. The new compounds can be easily attached on the graphene surface and provide functional groups at the end of the chemical compounds. Moreover, we proposed a simple protocol for immobilizing the natural receptors on the graphene surface in field-effect transistor system (FET). The receptor-conjugated graphene FET showed high sensitivity and selectivity toward biocides, odorants, and decomposition.

Resume : Polydopamine (PDA), which is easily formed by the auto-oxidative polymerization of dopamine. We have previously reported a self-assembled formation of thin polydopamine film (nm-scale) at air/water and oil/water interface. Although the film formed at the air/water interface can be transferred on solid substrates, some cracks appeared during the process, and the film was not stable when the vessel was slightly shaken. To improve a mechanical fragility of PDA films obtained from the air/water interface, we added the polymer containing amino group to the dopamine solution since dopamine and these groups were conjugated via Michel addition and Shiff base reaction. We present self-assembled composite films consisting of polydopamine and gelatin which is known as a biocompatible polymer and has amino group. Dopamine (10 mg/mL) and gelatin (100 mg/mL) were dissolved in Tris-HCl solution (pH 8.9). The brown-colored composite film was self-assembly formed at the air/water interface after 24 hours. The film picked up from the air/water interface was gel-like, robust and flexible. From an SEM cross-sectional image, the thickness of the dried film was over 100 μm. Additionally, by forming 3 dimensional (3D) shaped air/water interface with a sacrifice, 3D structured polydopamine composite films such as a rod and tube shape were obtained. From above results, we successfully obtained robust 2D and 3D polydopamine composite films via self-assembly process.

Resume : Carbon nano-onions (CNOs) [1] are multi-shell fullerenes, structured by concentric shells of sp2 carbon atoms. These materials can be easily produced in high quantities by thermal annealing of detonation nano-diamonds. CNOs represent an interesting platform for imaging and diagnostic applications [2] due to their spherical shape, small size, and low toxicity both in vitro [2] and in vivo [3]. In this work we developed a nano-carrier based on 5nm CNOs functionalized with folic acid for potential targeted delivery applications. We decorated the folic acid functionalized CNOs with a chemotherapeutic agent, doxorubicin, using a non-covalent functionalisation strategy and evaluated their specificity and cytotoxicity towards the cancer cell line HeLa CCL2. Robust characterization techniques, such as infrared and absorbance spectroscopy, thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS), confirmed the successful functionalization of the nano-carriers with the drug. Our findings indicated the cyto-compatibility of functionalized CNOs without doxorubicin. On the other hand the presence of folic acid on the nano-carrier is key to selectively drive the drug inside the cells, and ultimately causing their death. Our functionalized CNOs, selective for and rapidly up-taken by cancer cells, can open new opportunities for low-cost and biocompatible platforms capable of in vivo selective tumor accumulation of a drug. [1] Bartelmess, J. and Giordani, S. Beilstein J. Nanotechnol. 2014, 5, 1980. [2] Lettieri, S.; Camisasca, A.; d?Amora, M.; Diaspro, A.; Uchida, T.; Nakajima, Y.; Yanagisawa, K.; Maekawa, T.; Giordani, S. RSC Adv. 2017, 7, 45676 [3] d?Amora, M.; Camisasca, A.; Lettieri, S.; Giordani, S. Nanomaterials 2017, 7, 414

Resume : About sixty years ago, the biological cell counter with an electrical currents detection technique through a micrometer size orifice was invented by Dr. Coulter. A couple of years ago, the ultrafast portable pore device (MinION) with an electrical detection technique was manufactured by Oxford Nanopore Technology. However, high error rates over 80 % from this solid state nanopore device is initially reported in several journals. The high error rates may have been contributed from the electrical double layer formed in the pore channel. Even though the error rates have been reduced significantly. Considering the fact that most biosensors are utilizing the optical detection technique and the carbon filters have a slit-type structure with ~ 5 nm gap, the optical slit pore device can be an excellent candidate for the next generation single molecule sensor. We will report the fabrication process of the plasmonic optical slit nanopores

Resume : The use of biomaterials such as diatom silica frustules is highly attractive for removing toxic metals from aquatic environments due to their low-cost and abundant supply from natural biomineralization. However, diatoms are composed by an amorphous SiO2 core, which posses very limited properties. Therefore, new approaches are needed to functionalize diatom-based nanostructures to expand their range of useful properties while preserving or appropriately modifying its original nanostructure. In this work, we carry out a systematic density functional theory (DFT) study on the adsorption mechanism of heavy metals and simple biomolecules at several surface-modified crystalline and amorphous silica surfaces. Our results show that the involvement of various functional groups such as surface silanol (SiOHx) or amino groups enhance the diatom capacity to absorb heavy metals like Hg or Cd. The outcomes of these simulations give us a comprehensive insight on the adsorption mechanism of heavy metals at silica-based materials and can be used to support experiments for the development of novel adsorbents biomaterials for their use in environmental applications.

Resume : The ability to detect bone extracellular matrix proteins would be beneficial for developing a diagnostic tool for measuring bone growth juxtaposed to an orthopaedic implant. Osteocalcin, osteopontin, osteonectin, and bone sialoprotein are important proteins of bone-forming cells that are secreted during osteoblast differentiation and bone extracellular matrix formation. Electrochemical behaviors assessed by cyclic voltammetry of osteocalcin, osteopontin, osteonectin, and bone sialoprotein demonstrated that anodized titanium electrodes with an electrodeposited coating of graphene oxide were able to detect these proteins by graphene oxide-mediated electron transfer. The increased sensitivity produced by coating the anodized titanium electrodes with graphene oxide for detecting low concentrations of proteins might be due to the increased surface area and improved electron transfer of the electrodes. Importantly, the level of secreted osteoblast proteins detected using the modified electrodes indicated the presence of bone formation and matrix mineralization. This study revealed that osteoblast proteins could be detected using anodized titanium electrodes coated with graphene oxide by electrodeposition, and this method could be used for developing a new in-situ sensor to detect bone growth for orthopaedic diagnostics.

Resume : The synthesis of biocompatible films from aminomalonitrile (AMN) based solutions is a new versatile surface functionalisation method using a precursor molecule which may have played an important role in prebiotic chemistry. We will describe the electrodeposition of AMN based films [1] and we will show in this presentation that the deposition from solution is preceded by a lag phase which duration is dependent on the solution concentration of the precursor. The deposition process was followed by means of quartz crystal microbalance with dissipation monitoring as well as by UV -vis spectroscopy, leading to the estimation of the film deposition rate. For all the investigated solution concentrations, the obtained films are superhydrophilic after long reaction times (>10 h). During deposition, the AMN based deposits undergo morphological and compositional changes. Of the highest interest is the different composition of the films deposited on silicon with respect to the composition of the AMN based aggregates formed in solution; suggesting that the surface allows to control the chemical pathway leading to the final material. This is of particular interest from the point of view of prebiotic Chemistry. [1] Ball, V.; Toh, R.J.; Voelcker, N.,; Thissen, H.; Evans, R. (2018) Electrochemical deposition of aminomalonotrile based films. Colloids and Surfaces A: Physicochem. Eng. Asp. 552, 124-129.

Resume : Abstract Intracellular delivery of nanocarriers containing different biopharmaceuticals requires the release of the nanocarriers to the cytosol by endosomal escape.1 Various researches are going on to develop efficient nanocarriers made of different pH-sensitive polymers, which can trigger endosomal escape, by pH-induced structural change. Poly(ethylenimine) (PEI) is one of such pH-sensitive polymer, which has been widely explored for non-viral gene delivery and for designing Nanocarrier vehicle, efficient for therapeutic release to the cytosol. The mechanism behind high efficiency of PEI for endosomal escape has been explained by the well-accepted Proton-sponge hypothesis.2 This hypothesis emphasizes high buffering capacity of PEI inside lysosome along with a subsequent increase in lysosomal pH is the main factor behind the endosomal escape. However, evidence, which proves lysosomal pH change in presence of PEI, remains questionable. Herein we are using SNARF loaded polyelectrolyte capsule as an intracellular pH sensor to study whether PEI can modulate lysosomal pH. SNARF is a pH sensitive dye and it has dual emission property which enables ratiometric pH sensing without using any other reference fluorophore. Loading SNARF inside capsule offers several potential advantages.3 This capsule system has been used to measure pH of lysosome in presence of different branched and linear PEI at different concentration and different exposure time by Flow cytometry analysis. A detailed quantitative study has been performed to understand the proton sponge effect of PEI and its role on endosomal escape. References (1) Forrest, M. L.; Pack, D. W. Molecular Therapy 2002, 6, 57. (2) Creusat, G.; Rinaldi, A. S.; Weiss, E.; Elbaghdadi, R.; Remy, J. S.; Mulherkar, R.; Zuber, G. Bioconjug. Chem. 2010, 21, 994. (3) Kantner, K.; Ashraf, S.; Carregal-Romero, S.; Carrillo-Carrion, C.; Collot, M.; del Pino, P.; Heimbrodt, W.; Jimenez de Aberasturi, D.; Kaiser, U.; Kazakova, L. I.; Lelle, M.; Martinez de Baroja, N.; Montenegro, J.-M.; Nazarenus, M.; Pelaz, B.; Peneva, K.; Rivera Gil, P.; Sabir, N.; Schneider, L. M.; Shabarchina, L. I.; Sukhorukov, G. B.; Vazquez, M.; Yang, F.; Parak, W. J. Small 2015, 11, 896.

Resume : Enzymatic biofuel cells (EBC) using glucose and oxygen fuels are devices converting chemical energy of the fuels to electrical energy by enzyme based biocatalysts. Since the EBC can operate even in physiological conditions, glucose and oxygen contained in human body fluid can be utilized as the fuels for implantable devices. However, in spite of that, there are still problems to be addressed. As one of them, there is a slow reaction rate of the biocatalyst. To solve the problem, introducing a new mediator with the enzyme and substrate materials can be considered. When the mediator is applied, electron transfer for both anodic and cathodic reactions is facilitated and the associated reaction rate, followed by the produced current, is enhanced. To optimize the electron transfer, here, we suggest a new electron transfer mechanism, so called, a mediator embedded electron transfer (EMET). According to our EMET mechanism, mediator properly immobilized onto the enzyme and substrate materials shuttles the electron effectively and as a result, the drawbacks of conventional direct or mediator electron transfer mechanism can be alleviated. In this regard, when it comes to anode, glucose oxidase (GOx) enzyme and dye mediator are used for the purpose and as for cathode, GOx and porphyrin mediator are used. By the use of the redox couple, the activity of the biocatalysts and the performance of EBCs using the biocatalysts were excellent. In this conference, I will explain the related electron transfer theory, the synthetic procedure of corresponding biocatalysts and the configuration and performance of EBC utilized.

Resume : Multi-shell fullerenes, known as carbon nano-onions (CNOs), are structured by concentric shells of carbon atoms and are emerging as platforms for biomedical applications because of their ability to be internalized by cells and low toxicity. [1]. In my research group we have developed a synthetic multi-functionalisation strategy for the introduction of different functionalities (receptor targeting unit and imaging unit) onto the surface of the CNOs The modified CNOs display high brightness and photostability in aqueous solutions and are selectively taken up by different cancer cell lines without significant cytotoxicity. [2]. To probe the possible applications of CNOs as a platform for therapeutic and diagnostic interventions on CNS diseases, we injected fluorescent CNOs in vivo in mice hippocampus. We analyzed ex vivo their diffusion within brain tissues and their cellular localization by confocal microscopy, electron microscopy, and correlative light-electron microscopy techniques. The subsequent fluorescent staining of hippocampal cells populations indicates they efficiently internalize the nanoparticles. Furthermore, the inflammatory potential of the CNOs injection was found comparable to sterile vehicle infusion, and it did not result in manifest neurophysiological and behavioral alterations of hippocampal-mediated functions [3]. These results encourage further development as brain disease-targeted diagnostics or therapeutics nanocarriers. [1] S. Giordani et al., Current Medicinal Chemistry 2018, in press. [2] M. Frasconi et al., Chem Eur J 2015, 21 (52), 19071. [3] M. Trusel et al., ACS Appl. Mat. & Inter. 2018, 10 (20), 16952.

Resume : Nanoparticles (NPs) have many diverse applications in life- and physical sciences. There is a tremendous interest in understanding the impact of the nanoparticle systems on the living organisms as the interaction determines the physiological response and effects of the NPs on living systems, including cellular uptake, circulation lifetime, signalling, therapeutic effects, and toxicity. Proteins are able to adsorb onto the surface of larger NPs forming a dense protein coating known as protein corona. Considering that most plasma proteins present a hydrodynamic diameter of about 3-15 nm, the behaviour of NPs < 3 nm in biological systems, could be dramatically different from that of larger particles. We propose that restricted diffusion behaviour of the ultrasmall nanoparticles (USNPs) in the vicinity of the proteins should be considered as an additional reaction type when NPs interact with proteins using silicon carbide NPs and BSA as a model system. The transient particle?protein associations can manifest themselves in a physical complex formation that determines the characteristics. The biological behaviour of silicon carbide USNPs in a medium modelling a living organism was investigated in detail. The interaction shows transient nanoparticle-protein associations due to the restricted diffusion behaviour of the nanoparticle in the vicinity of a protein. By studying silicon carbide NPs in different sizes, it can be concluded, that the transient effect is an USNP behaviour.

Resume : Carbon dots (CDs), a new class of zero-dimensional nanomaterials, have attracted great interest in the nanomedicine because of their versatile merits such as biocompatibility, facile functionalization, and tunable photoluminescence. Here, we present the new design of CDs that highly inhibit the aggregation of amyloid-? (A?) peptides. The abnormal aggregation of A? peptides is a major hallmark of Alzheimer?s diseases (AD) that affects 11% of people aged over 65. Despite numerous researches, effective suppression of A? aggregation is still challenging due to multifactorial pathogenesis involving high levels of metal ions in the brain; copper ions (Cu(II)) have drawn significant attention in AD pathogenesis because of their high activities in forming neurotoxic A?-Cu(II) aggregates. To provide a new strategy in the prevention of Cu(II)-associated A? aggregation, we have synthesized the multifunctional CDs that are capable of (1) Cu(II) coordination, (2) interrupting A? self-assembly, and (3) oxidizing A? residues. Nitrogen-containing moieties of as-prepared CDs did a key role in interact with Cu(II) and A??s aggregation sites by electrostatic and hydrogen/hydrophobic interactions. Interestingly, Cu(II)-bound CDs enhanced their fluorescence, further induced the generation of reactive oxygen species (ROS) under light irradiation. The resulting ROS then photodynamically oxidized A? residues (e.g., histidine) to lose the affinity towards Cu(II) and A??s aggregative property. The CDs? simultaneous inhibitory effects significantly mitigated the neurotoxicity of A?-Cu aggregates, showing 96% of cell viability. Our work highlights the therapeutic potential of CDs for future A?-targeted AD treatments.

Resume : Polydopamine (PDA) formed by the oxidation of dopamine is a substance that can coat the surface of almost all known materials? surfaces. However, its synthesis is usually accompanied by the production of amorphous precipitates in solution. The similarities observed between the PDA and eumelanin, the black brown pigment responsible for the coloration of the skin and hairs, induced to produce stable and size-controlled nanoparticles in solution. Inspired by the presence of proteins in natural eumelanin grains, we could demonstrate that a specific diad of amino acids in proteins [1], namely KE, allows for a specific control in the formation of PDA nanoparticles. We then demonstrated that colloidally stable PDA@protein nanoparticles, which are biocompatible in addition, can be obtained in acidic conditions, where spontaneous auto-oxidation of dopamine is suppressed, using sodium periodate as the oxidant and a protein, like alkaline phosphatase (ALP), as a templating agent [2]. The size of the obtained PDA@ALP nanoparticles depends on the dopamine/enzyme ratio and they display the enzymatic activity of alkaline phosphatase, with an activity extending up to two weeks after particle synthesis. These PDA@ALP nanoparticles can be incorporated in polyelectrolyte multilayered films to potentially design model biosensors or can be used as additives for biocompatible hydrogels. [1] Bergtold, C.; Hauser, D.; Chaumont, A.; El Yakhlifi, S.; Mateescu, M.; Meyer, F.; Metz-Boutigue, M.-H.; Frisch, B.; Schaaf, P.; Ihiawakrim, D.; et al. Mimicking the chemistry of natural eumelanin synthesis: The KE sequence in polypeptides and in proteins allows for a specific control of nanosized functional polydopamine formation. Biomacromolecules 2018, 19, 3693?3704. [2] El Yakhlifi, S.; Ihiawakrim, D.; Ersen, O.; Ball, V. Enzymatically Active Polydopamine @ Alkaline Phosphatase Nanoparticles Produced by NaIO4 Oxidation of Dopamine. Biomimetics 2018, 3, 36S

Resume : In tissues, gradients of oxygen and nutrients extend radially from blood vessels. The steepness of these gradients increase significantly when a blood vessel is occluded, or in the case of the tumors when the rate of proliferation outpaces the rate of vascularization. The extent of hypoxia in tumors has been correlated with cancer aggressiveness, drug resistance, and invasiveness. Despite the pivotal role that the extracellular environment plays in tumor biology, there are a limited number of in vitro assays able to quantify cellular morphology, gene- and protein-expression, or drug sensitivities in well-defined oxygen or nutrient gradients. This presentation will discuss two applications of our recent efforts to develop 3D co-culture models of healthy and tumorigenic breast tissues. These cultures utilize paper scaffolds as supports; can be assembled into tissue-like architectures; are readily prepared in 96-culture formats that are amenable to screening in traditional well plate readers. In the first application, I will show the importance of co-culture formats when predicting the in vivo potency of endocrine disrupting chemicals. This example will highlight our efforts to not only prepare a more representative screening platform but also to develop technologies to monitor intercellular signaling in 3D cultures in real-time. In the second application, I will show that abiotic gradients in the microenvironment play a critical role in modulating estrogen sensitivity. This example will highlight our efforts to quantify the spatial and temporal formation of gradients in our 3D cultures and relate those gradients to cellular responses.

Resume : Engineered-nanotubular structures offer exciting progress toward the design of multifunctional medical implants. Using facile electrochemical technique based on low cost electrode materials, we have been able to fabricate three-dimensional high quality self-aligned nanotubes on the surface of arbitrary geometries. Biocompatibility studies were conducted with MG-63 and human mesenchymal stem cells (hMSCs) through MTT assay. Furthermore, cell morphology and cytoskeleton organization were observed by SEM and laser scanning confocal microscopy (LSCM). The osteoblastic differentiation capacity of hMSCs was studied by real-time PCR, as well as their angiogenesis ability by measuring the total release of vascular endothelial growth factor (VEGF). Finally, viability of Staphylococcus aureus (S. aureus) was assessed by live/dead bacterial viability assay. Results show that bio-functionalized TiO2 nanotubular surfaces are biocompatible and modulated cell morphology. Such novel bio-selective implant surfaces are able to improve osseointegration and avoid infection simultaneously. In addition they can prevent unnecessary side effects caused by oral administration of drugs, increase drug efficiency, and prevent infection related implant complications and failures.

Resume : In the field of cardiac tissue engineering the incorporation of metal nanomaterials into artificial extracellular matrices has led to improved functioning of engineered cardiac patches through enhanced mechanical and electrical properties [1]. Moreover, the environment-sensitive electrical, magnetic or optical properties of nanoparticles can potentially be used to monitor the proper, native-like functioning of the tissue construct. In this work, we developed nanofibrillar cellular matrices where semiconductor nanocrystals (quantum dots, QDs) are attached onto collagen fibers for in situ, optical monitoring of cardiomyocyte activity. Collagen, abondantly present in natural extracellular matrices, displays multiple cell binding motives and therefore enhances QD localization in respect to the cell membrane. On the other hand, the optical properties of QDs are modulated by cellular responses (like membrane electric fields or mechanical deformation) and can therefore be used for in situ cellular monitoring. We demontrate optical readout of the activity of primary rat cardiomyocytes cultured on top of such hybrid matrices by the QD two-photon fluorescence . Cardiomyocytes cultured on hybrid scaffolds display satifactory cell viability compared to control substrates and the method can easily be extended to 3D tissue constructs for future applications. [1] Kankala, R. K. et al., ACS Biomaterials Science and Engineering. 2018.

Resume : Electrospun solid fibers have been utilized as porous scaffolds for a variety of three-dimensional (3-D) cell cultures but there still exist practical issues such as low optical transparency, unfavorable mechanical stiffness, poor dimension controllability, etc. In this research, we developed natural polymer-based colloidal hydrogel fibers (e.g. gelatin fibers) with positive or negative charges. The resultant colloidal fibers exhibited excellent biodegradability, high optical transparency, controllable mechanical properties, and stable dispersion in water. Subsequently, the electrostatic interaction was introduced between positively- and negatively-charged colloidal fibers, leading to the entangled hydrogel fiber network with microscale porosity. Furthermore, it was demonstrated that charge density, overall diameter, and swelling ratio of colloidal hydrogel fiber can be easily modulated to optimize these novel hydrogel scaffolds suitable for various types of 3-D cell cultures.

Resume : The controlled immobilization of functional bio- or inorganic nanoparticles (NPs) on nanopatterned substrates is a highly flexible way to render tailored surface characteristics for smart biointerfaces: protein arrays can create functional hot spots guiding cell response, while arrays of metallic nanoparticles with plasmonic properties can be applied in biosensing. For the creation of such NP arrays, a fundamental understanding of colloid-solid interactions and deposition processes is, however, indispensable. We apply self-assembly techniques to design highly ordered large-area nanoobject arrays on nanopatterned surfaces. We employ block copolymer lithography for the patterning of glass, silicon or titanium surfaces with sub-20 nm features to tailor the surface morphology, i.e. topography and local surface chemistry. Particularly, we present arrays of nanopores with a diameter of 17 nm, which we then use as templates for the deposition of NPs. We exploit convective self-assembly to deposit NPs with diameters of 5-14 nm selectively inside nanopores and create ordered arrays with a pattern density of 10^11 cm^-2. In particular, we use Au NPs as model system and ferritin NPs as bio-NPs. Thus our findings can be transferred to various material systems and elucidate solid-bio interactions. We investigate the colloid-solid interactions by measurements of surface and particle zeta potentials as well as surface wettabilities and analyse the NP arrays by SEM, AFM and TEM.

Resume : Paramagnetic chelates have seen application in a number of fields and are well known for their roles in medicine, particularly in enhancing the potency of the powerful non-invasive imaging technique magnetic resonance imaging (MRI). Research towards the design of high performing and functional MRI contrast agents based on paramagnetic chelates has advanced enormously in recent years. In particular, the exploitation of nanoscale carriers has expanded the toolkit of this imaging technique, facilitating targeting and the potential for diagnostic as well as therapeutic delivery agents. Responsive MRI contrast agents, which can provide accurate disease diagnosis through a change in image contrast triggered by a specific stimulus or biochemical variable, represent the next milestone in non-invasive disease diagnosis and management. In this talk, I will describe our efforts towards optimizing the design of nanoscale contrast agents which can provide high signal contrast at exceptionally low doses. I will further describe our latest research into ?switchable? imaging contrast from a modified mesoporous silica nanoparticle scaffold doped with gadolinium-chelates (Gd-MSNs) and externally grafted with a thermoresponsive polymer (polymer-Gd-MSNs). These particles exploit a selective environmental response which is capable of localizing strong MRI signal at the stimulus site, providing a clear and identifiable site identification (and hence potential diagnosis). This proof-of-concept work is of significant value in the emerging field of diagnostic MRI.

Resume : Carbon nanohorns (CNH) are attractive systems for cellular imaging, diagnostics and therapeutics due to their low toxicity, high surface area, and ease of functionalisation.1,2 This work reports the use of CNHs for (i) non-covalent uptake of porphyrin drug molecules and (ii) covalent loading of gold nanoparticles. The poor cellular uptake of many porphyrins is a barrier to their application in phototherapeutic applications,2 biocompatible CNH carriers offer a means to overcome this. The binding interactions of two cationic porphyrins, PtTMPyP4 and H2TMPyP4 have shown very high affinity to oxidised carbon nanohorns through non-covalent, electrostatic interactions. Brightfield microscopy demonstrated the efficacy of sparsely loaded Porphyrin-CNH constructs to be internalised within HeLa cells, which undergo rapid cell death upon visible excitation. In the past decade, gold nanoparticles have been used in biomedical applications for sensing, drug delivery and more recently radiosensitization of resistant cancer cells.4,5 Yet they are prone to aggregation in ionic or biological environments. Immobilisation of gold nanoparticles onto ligand functionalised CNHs allows for the utilisation of their therapeutic properties, reducing the risk of aggregation. Readily dispersed, CNH supported gold nanoparticles have shown to have increased stability in buffer and cell media compared to free gold and are excellent candidates for radiosensitization. 1) S. J. Devereux, et al. Chem. Eur. J., 2018, 24, 14162-14170. 2) S. Iijima, et al. Chem. Phys. Lett. 1999, 309, 165 3) M.A. Rajora, et al. Chem. Soc. Rev., 2017, 46, 6433. 4) S. A. Belhout, et al. Chem. Commun., 2016, 52, 14388-14391 5) W. Roa, et al. Nanotechnology, 2009, 20, 375101.

Resume : We have prepared various all-organic magnetic soft materials containing a cyclic nitroxide radical moiety as a spin source [1]. In this talk, we report the preparation of all-organic magnetic nanoemulsions composed of the non-ionic surfactant and the hydrophobic nitroxide radical compound [2]. The properties of the nanoemulsions have been investigated by small angle neutron scattering (SANS) and dynamic light scattering (DLS) analyses, EPR spectroscopy, and MRI method. The nanoemulsions showed high colloidal stability, high reduction resistance to ascorbic acid, low cytotoxicity and an enough contrast enhancement in the proton longitudinal relaxation time (T1)-weighted MR images in (-)-PBS in vitro and in vivo. Furthermore, an additional hydrophobic anticancer drug such as Taxol® was simultaneously encapsulated inside the nanoemulsions. We expect that the drug-loaded nanoemulsions can be used as a biocompatible magnetic drug carrier for MRI-visible targeted delivery system. [1] a) Uchida, Y.et al. J. Mater. Chem. 2009, 19, 6877; b) Uchida, Y. et al. J. Am. Chem. Soc. 2010, 132, 9746; c) Takemoto, Y. et al. Soft Matter 2015, 11, 5563 [2] Nagura, K, Komatsu, N., Tamura R., at al., Chem. Eur. J., 2017, 23, 15713; Pharmaceutics, in press.

Resume : The unique physicochemical properties of gold nanoparticles (AuNPs) make them highly applicable for drug release, optoacoustic imaging, biosensing and photothermal therapy. This work highlights new methodologies for the encapsulation of AuNPs in chitosan hydrogels in order to increase their applicability and efficacy in health-related applications. AuNPs can be employed in photothermal therapy (PTT) applications as efficient light-to-heat transducers for the selective ablation of target cells. We have compared the heating capability, cellular internalization, toxicity and thermoablation capacity of two different types of anisotropic AuNPs: gold nanorods (AuNRs) and nanoprisms (AuNPrs) [1]. Our studies have shown that both AuNPs were highly efficient photothermal converters, but AuNRs possess a more efficient heating capability. Nevertheless, in vitro thermoablation studies demonstrate that AuNRs display an extremely poor cellular internalization thereby limiting their application. To improve the PTT application of AuNRs we have entrapped them inside cell-adhesive chitosan hydrogels to produce functional nanocontainers with the ability to adhere to the cytoplasmic membranes of cells, avoiding any need for cellular internalization and thus rendering them as highly efficient PTT agents [2]. Neverhteless, one key disadvantage of this entrapment methodology is the relatively limited control of the size and size-dispersion of the nanocontainers. To improve these drawbacks we have developed a novel strategy for AuNP microencapsulation in chitosan hydrogel using a high-throughput, continuous and automatic inkjet printing. This scalable industrially relevant approach has offers a high rate of production, excellent control of the microcapsules size and high encapsulation efficiency; obtaining monodisperse chitosan microcapsules containing AuNPs. We have demonstrated that these microcapsules did not display cellular toxicity in vitro and are extremely resistant to pHs, gastric and colon simulated medium degradation. [3] For these reasons we are currently studying the use of these chitosan hydrogels for oral administration of AuNPs in vivo, analyzing their retention in the digestive tract thanks to their muco-adhesive properties and the liberation of AuNPs in the intestine and their absorption to the bloodstream of mice. References [1] Artiga, Á., Alfranca, G., Stepien, G., Moros, M., Mitchell, S. G., and de la Fuente, J. M. (2016). Nanomedicine 11, 2903?2916. doi: 10.2217/nnm-2016-0257 [2] Artiga, Á., García-Embid, S., Matteis, L. D., Mitchell, S. G., and de la Fuente, J. M. (2018). Front. Chem. doi: 10.3389/fchem.2018.00234 [3] Artiga, Á., Serrano-Sevilla, I., Matteis, L. D., Mitchell, S. G., Sánchez-Somolinos, C., and de la Fuente, J. M. (2018). Chem. Comm. (In preparation)

Resume : Recently, some groups reported that cancer cells might starve to death by blocking them obtain nutrition such as glucose, indicating the starving therapy is a potential way for cancer treatment. However, the hypoxia condition in tumor microenvironment may inhibit the efficacy of starving therapy. Herein, we developed a combined photothermal/starving therapy for cancer treatment. First, we synthesized Au shells (GNs, photothermal agent) and then reduced Pt on them to form GN@Pt (catalyst for H2O2 decomposition). The synthesized particles could convert the NIR light to heat the solution up to 60 ?. Then, they could efficiently catalyze the decomposition of H2O2 and thus the generated O2 concentration reached ~7 ppm in 30 min. More importantly, the GN@Pt display great thermal and chemical stability for repeated-photothermal therapy and long-term hypoxia improvement, respectively. After mixing GN@Pt, glucose oxidase (GOx) and silk fibroin solution together to form an injectable hydrogel solution (SFs/GN@Pt+GOx), we evaluated H2O2 decomposition ability and glucose oxidation ability of the composite hydrogel. Moreover, we proved the anti-cancer ability of SFs/GN@Pt+GOx in hypoxia condition in vitro. Finally, in order to confirm the efficacy in vivo, the hydrogel was orthotopically injected into mice bearing with 4T1 breast cancer and followed by laser irradiation in several days. The preliminary data shows that our method would be a potential way for breast cancer treatment.

Resume : Dopamine (DA) is known as one of the most important neurotransmitters in mammals and its detection is currently a subject of significant interest. Indeed, real-time determination of DA is crucial in the diagnosis of several neurological disorders, such as Parkinson?s disease, autism and schizophrenia. However, typical concentration values do not exceed the nM range in biological samples, where ubiquitous interfering agents, such as Uric Acid (UA) and Ascorbic Acid (AA), can be found in concentrations up to 100-1000 times higher. For these reasons, common chemical sensors do not exhibit an adequate sensitivity for in vivo applications. Differently, Organic Electrochemical Transistors (OECTs) are bioelectronic devices that have recently attracted large attention in the biomedical arena for the high provided sensitivity, together with biocompatibility and low-cost. On one hand, thanks to the intrinsic signal amplification given by the transistor configuration, the OECT could be a tool for reliable detection of dopamine in biological fluids. On the other hand, the selectivity issue must be addressed to allow its widespread use in real-life applications. In this work we explore a new approach to selectively identify and determine the contributions of different analytes, i.e. DA, UA and AA, to the OECT electrical output signal through a linear scan of the gate potential.[1] OECT sensors were entirely made of PEDOT:PSS as both channel and gate material in order to take advantage of the peculiar electrochemical properties of the conducting polymer. First, we carried out electrochemical characterisation to achieve a deeper insight into the electrochemical processes occurring at the polymeric gate electrode, showing that the oxidation of the three analytes takes place at different potentials. After that, we proposed a new potentiodynamic approach, demonstrating that the all PEDOT:PSS OECT can selectively detect the three different analytes when present in the same solution, as their oxidation occurs at different gate potentials. Finally, the signal related to each compound can be individually resolved by means of the OECT transconductance and the sensor exhibits a very sensitive linear response for all the analytes. [1] I. Gualandi, D. Tonelli, F. Mariani, E. Scavetta, M. Marzocchi and B. Fraboni, Scientific Reports, 2016, 6, 35419

Resume : Development of controlled release biomolecules by encapsulating into Nano Hydroxiapatite (HA-Np) have recently gained popularity. However, the impact of the surface morphology of HA-Np on the encapsulation mechanism of these biomolecules remain to be explored. Ureas are used in applications in medicinal chemistry as a model system for the design and optimization of various therapeutic agents. The unique hydrogen binding capabilities of ureas make them an important functional group in molecules with broad range of bioactivities. Morphologically different HA-Np thin films that specifically expose (100) and (002) planes were fabricated on the quartz crystal piezoelectric sensors. These planes mainly consists Ca and PO4-3 sites respectively. Electrophoretic deposition and spin coating techniques were used without high temperature sintering for HA-Np sensor fabrication. Urea adsorption onto both Ca and PO4-3 sites were monitored, in the PBS buffer, in-situ and in real time from the quartz crystal microbalance. The above adsorption data, sigmoidal in shape, were fitted with three different sigmoidal models which include Logistic model, Weibull model and Emperical Hill model (EHM) with the latter giving the best fit for the data. Kinetic parameters derived from the fit to EHM, show that adsorption rates of urea on the Ca site is higher than that onto the PO4-3 site. Moreover the affinity of urea to multiple binding sites of HA-Np leads to Cooperative binding. Modelling information shows that the cooperative parameter of the Ca site is also higher than the PO4-3 site. Kinetic and cooperative parameters reveal that the Ca site of HA-Np is more favourable as a functional coating in sensing applications and in development of controlled release drugs and fertilizers.

Resume : Angiogenin (ANG), involved in most stages of the angiogenesis process, has been shown related to many pathophysiological processes, including tumorigenesis, neuroprotection, inflammation and regeneration of damaged tissues [1]. In this work, we investigated a hybrid made of ANG assembled to gold nanoparticles and graphene oxide nanosheets, to exploit the synergic effects of antioxidant AuNP [2] and antimicrobial GO [3], respectively. Au-GO-ANG were characterized by UV-visible spectroscopy, to correlate the changes in the plasmonic peak as well as in the π*-π transitions to the protein interaction with Au and GO, respectively. AFM and DLS measurements confirmed the strong association of the protein both to the nanoparticles and to the nanosheets. Lipid lateral diffusion and viscoelastic changes measured by FRAP and QCM-D within supported lipid bilayers pointed to a strong interaction of the nanocomposites with the model cell membranes. The developed systems promoted fibroblasts migration and wound closure, and cell viability assays showed low cytotoxicity. Confocal microscopy cell imaging evidenced dynamic processes at the level of cytoskeleton and sub-cellular compartments. References 1. Sheng et al., AABS, (2016) 48, 399. 2. Di Pietro et al., Curr Top Med Chem (2016) 16, 3069. 3. Mangadlao et al., Chem Commun (2015) 51, 2886.

Resume : Numerous therapeutic nanocarriers have been developed during the last decade. For nanomedicine, nanomaterials need to be coated to prevent protein adsorption and hepatic capture. Here, we examine the formation of supported lipid bilayer (SLB) on spherical nanoparticles as an alternative coating strategy. Negative and positive silica nanoparticles (diameter 50 to 100 nm) were studied in conjunction with synthetic (POPG, DOPC) and biological (Curosurf®, a pulmonary surfactant) lipids. Herein we demonstrate that contrary to recent literature reports, mixing particles and surfactant vesicles does not lead to spontaneous SLB formation. With oppositely charged species, aggregation is obtained. Applying in situ mechanical energy to mixed aggregates helps however reshaping the lamelarity through dispruption and reformation of the assembled structures, yielding to well-defined SLBs. The SLB formation was confirmed using cryogenic transmission electron microscopy. The stability of these structures in biological fluids in presence of proteins was finally demonstrated.

Resume : The complexity of biological membranes has motivated the development of models that can be supported on solids and electrodes. However, supported lipid bilayers often display poor stability in time [1]. In order to study the transmembrane antiporter NhaA protein [2] [3], we have developed an original approach aimed at increasing the stability of the lipid layer supported on an electrode thanks to electrografting. The cathodic reduction of aryl diazonium salts [4] generated in situ from 4-decylaniline (4DA) makes it possible to fix mixed vesicles (4DA and lipids) on the electrode surface. The grafted liposomes then break up and fuse to form supported lipid layers. Quartz microbalance studies with viscoelasticity measurements have been carried out to follow the fusion of mixed vesicles and to optimize the pH and salinity conditions. The stability of the supported lipid layer has been shown to increase from less than one day to about two weeks with the grating approach. Then, the insertion of either an active or inactive NhaA protein (a sodium / proton antiporter) in the supported lipid layer has been carried out by fusion of proteoliposomes [5]. This has been followed by cyclic voltammetry and electrochemical impedance spectroscopy onto an electrode modified by an adsorbed pH sensor (2-anthraquinonesulfonate) [6]. [1] D. W. Jeong, et al., Nature Scientific Report. 2016, 6, 38158-38165 [2] D. K. Martin et al., “Liposomes, Lipid Bilayers and Model Membranes: From Basic Research to Application” eds: Pabst G, Kucerka N, Nieh MP, Katsaras J. CRC Press, Taylor & Francis Group, 2013 [3] Project bioWATTs-ANR-15-CE05-0003 [4] D. Bélanger, J. Pinson, Chemical Society Reviews, 2011, 40, 3995-4048 [5] G. J. Hardy et al., Current Opinion in Colloid & Interface Science, 2013, 18, 448–458 [6] C. Batchelor-McAuley et al., The Journal of Physical Chemistry B, 2010, 114, 4094–4100

Resume : To date, 2 photon-polymerisation (2PP) has proven an effective micro/nanofabrication tool for the realisation of high-resolution structures from UV-curable photoresists. Exploiting commercially available resins such as SU-8, Ormocomp, and IPL has yielded structures with features smaller than 100 nm.[1] There exists a challenge for the materials chemist to develop a means of adaptability which will enable extension of this impressive tool to encompass biocompatible smart polymers, either via direct printing of nanoscale structures, or via replica moulding from 2PP generated patterns.[2,3] In this work we present the generation of 2D and 3D micro- and nano-sized structures fabricated from optimised cocktails of biocompatible monomers. The use of 2PP-produced structures as replica moulding masters will also be presented. The ability to cast high-fidelity mm-sized arrays from a wide range of materials, while retaining the nanostructure, will be demonstrated. Characterisation of these millimetre arrays using SEM, AFM, and Confocal Microscopy showcases the potential of this approach as a novel means of generating high-resolution nanostructures for use at the biological-surface interface.[4] [1] Appl. Phys. Lett. 90 (2007) 71106. [2] Sci. Rep. 8 (2018) 564. [3] Polym. Adv. Technol. 23 (2012) 992–1001. [4] Sci. Rep. 7 (2017) 9247.

Resume : Nanoparticles based on porous silicon attract a lot of interest because of the outstanding properties of biocompatibility and biodegradability in the living environment. Wide opportunities of the surface modification, as well as efficient photoluminescence in the visible and infrared range, make them perfect agents for various theranostic applications, including targeted delivery of chemotherapeutic drugs. The current study is devoted to both theoretical and experimental investigation of sonoactivation of drug-loaded mesoporous silicon nanoparticles coated by biopolymers with the MHz-range ultrasound of moderate intensity. The role of two fundamental effects – acoustic cavitation and ultrasound-induced heat deposition – is taken into account. The presence of solid porous nanoparticles lowers the cavitation threshold in aqueous media due to the growth of air bubbles from nuclei and also leads to the heating of surrounding area due to the ultrasound energy absorption. In vitro experiments reveal the significant inhibition of cancer cell proliferation under the combined exposure to the nanoparticles and ultrasound radiation as compared to the intact group of cells. Investigation of the above physical effects at the nanoparticle/ bioenvironment interface has a great potential for the development of new strategies for the controlled drug release.

Resume : The World Commission on Environment and Development introduced the term sustainable development, indicating the present need of modern industrial processes to optimize the use of raw materials, reduce waste and avoid the use of toxic molecules. Amongst the approaches used over the years to achieve this sustainability, biocatalysts, especially enzymes, have been in the spotlight due to their great properties. Sustainability of enzymatic catalysis is maintained through the whole cycle: from their production (living organisms) to the waste treatment.[1] However, their present application at industrial scale is hampered by the high costs in their production that decrease cost-effectiveness of their application. Reutilization of the enzyme is therefore the tool to obtain more cost-effective and sustainable industrial processes. Immobilization of these biocatalysts allows an easy recovery of the material and protection from the reaction conditions in the different production steps.[2] Nowadays, nanotechnology offers one of the most forefront approaches for enzyme immobilization. Magnetic nanoparticles allow an easy recovery of an immobilized enzyme using a simple magnet to separate the catalyst from the reaction product. To improve colloidal stability of the support, reduce interactions between the magnetic cores and prevent interactions with the environment that can affect both support and enzyme stability, a polymer coating is an easy and cheap approach.[3] Using this approach, in this work we developed a hybrid, modular micro-support based on organic and inorganic nanocomponents. The easiness of tuning the composition of the support makes this system a potentially universal support for the immobilization of very different catalytic systems. Here we present the application of the developed micro-support for the immobilization of chloroperoxidase (CPO), an enzyme able to catalyze many reactions of large-scale interest. A multipolysaccharidic shell containing the immobilized enzyme and obtained through a combination of chitosan and alginate, biodegradable polymers from natural sources, was used to stabilize a nanoemulsion core in which magnetic nanoparticles were embedded. Microsupports obtained through different combinations of nanocomponents were characterized and tested in terms of their chemical stability under reaction conditions. An excellent reusability of the entrapped enzyme was observed opening the way to the immobilization of different catalytic systems and to the scale-up study in view of future industrial application.[4] References [1] R.A. Sheldon, J.M. Woodley, Chem. Rev. 118 (2018) 801–838. [2] M.L.E. Gutarra, L.S.M. Miranda, R.O.M.A. de Souza, in:, Org. Synth. Using Biocatal., Elsevier, 2016, pp. 99–126. [3] J. Xu, J. Sun, Y. Wang, J. Sheng, F. Wang, M. Sun, Molecules 19 (2014) 11465–11486. [4] S. García-Embid, F. Di Renzo, L. De Matteis, N. Spreti, J. M. de la Fuente, Appl. Catal. A Gen. 560 (2018) 94–102.

Resume : The electrochemical detection of a pH-dependent redox protein from electroactive bacteria at an electrode modified to act additionally as an efficient pH sensor based on a redox readout is demonstrated. The pH sensing electrode was previously designed and showed to allow the immobilization and study of pH-independent and redox active cytochrome c. Here we extend this work to flavocytochrome c3, a tetraheme FAD-containing periplasmic flavoenzyme isolated from the bacterium Shewanella putrefaciens, taken as a model pH-dependent redox protein from electroactive bacteria. The modification of the electrode surface with the pH sensing modifier (catechol) stems from our previous experience in the tailoring of bio-interfaces of carbon electrodes with covalent electrografting. Flavocytochrome c3 adsorption onto the modified electrode surface is successfully achieved by cyclic voltammetry in a flavocytochrome c3 solution containing polymyxin as co-adsorbate. The electrochemical activity of the immobilized flavocytochrome c3 is detected without alteration of its native structure and by keeping intact its electrochemical properties and its catalytic fumarate reductase activity. The redox activity of the protein arises from its FAD and four hemes cofactors. The experiments evidence that the hemes’ redox potentials of flavocytochrome c3 from Shewanella putrefaciens, for which no crystal structure is yet available, depend on pH which is at variance with data from the other strains.

Resume : Optical sensing of molecular oxygen has attracted a great deal of scientific attention since the determination of oxygen concentration is essential in diverse areas, ranging from life sciences to environmental sciences [1]. Fluorescent polymer nanoparticles (NPs) have received great attention due to their exceptional brightness, color tuning, potential biodegradability and low toxicity [2]. Herein, we demonstrate a simple approach for the FRET based ratiometric detection of dissolved oxygen (DO) gradients in live cancer cells using ultrabright polymeric nanoparticles. These nanoprobes are composed of dye-loaded PMMA-MA NPs, having the diameter of 40 nm. These polymeric nanoantennas can harvest energy from hundreds of donor dyes to a single acceptor, leading to the amplification of acceptor emission, which enables the detection at the single particle level. Here, the cyanine donors efficiently transfer their excitation energy to the porphyrin acceptor, whereas the acceptor phosphorescence is quenched by the presence of DO due to triplet-triplet energy transfer. The recovery of the acceptor phosphorescence occurs by varying the oxygen concentration in the mixture from 0 to 95%, which facilitates the ratiometric detection. The fabrication of a simple microfluidic prototype provides the stable cellular oxygen gradients, which permit the ratiometric imaging of hypoxic regions in tumor cells using wide-field fluorescence microscopy. [1] P. Carmeliet et al. Nature 1998, 394, 485-490. [2] K. Trofymchuk et al. Nat. Photonics 2017, 11, 657-663.

Resume : The dopamine plays a crucial role as a neurotransmitter for interneuronal communication in the brain, serious diseases such as Parkinson’s disease and Alzheimer’s disease be known to the effect of dopamine dysfunction. The conventional sensors for dopamine detection have been developed with various methods and one of them is field-effect transistor (FET) using conducting nanomaterials. Herein, we developed the portable and reusable FET device, the channel of the FET sensor was consisted multidimensional carboxylated poly(3,4-ethylenedioxythiophene) nanofibers, as we called a multidimensional conducting polymer nanofibers (MCPNFs). The MCPNFs via FET system rapidly measured various dopamine concentrations and showed high-selectivity and sensitivity (100 fM) in real-time. Based on those results, the MCPNF FET sensor can provide a practical methodology for obtaining a high-performance neurotransmitter detector.