Carbon materials: surface chemistry and biomedical applications II

Resume : Nanodiamond (ND) as a combination of an inert diamond core and chemically active surface terminations behaves interesting various properties. The mall size of particles (~5 nm) as well as specific assets determined via production method allows to widely custom this material for many biomedical applications. Up-to-date, ND has been used only as a nanomarker or nanocarrier, however, recent studies have shown also a great potential in radiosensitisation providing ND therapeutic abilities. Improvement of the conventional X-ray therapy in the cancer treatment is currently under investigation by many research groups around the world. High doses of irradiation in combination with aggressive chemotherapy cause a great damage in the human body. As a result, post-treatment side effects decrease a quality of patient’s life. Nanoparticles combined with X-ray can be an alternative cancer treatment method eliminating harmful side effects. Biologists have previously performed ‘’in vitro’’ experiments onto both radiosensitive and radioresistant cell lines treated with plasma hydrogenated nanodiamond (H-ND) and then irradiated [1]. Results showed that a significant increase in the production of reactive oxygen species (ROS) under irradiation is observed in the presence of H-ND. As a consequence, cancer cells are turned into senescence. In addition, this effect is also much higher compared to the traditional radiotherapy without NPs. Radiosensitising effect is a unique property of H-ND which is not observed for an oxidised type of nanodiamond (Ox-ND) with carboxylic termination. Radiosensitisation of H-ND needs to be explored more in order to understand the chemical, physical and biological effect behind it. In this study, a model previously used onto gold nanoparticles (GNP) [2] for quantification of hydroxyl radicals (•OH) production, was adapted for H-ND. Using the oxidised form of Coumarin (7-OH Coumarin) exhibiting a high fluorescence peak observed at 452 nm as a probe it is possible to estimate •OH production under different doses of X-ray irradiation. Coumarin in combination with the different concentration of H-ND was irradiated at 17 keV resulting in much higher 7-OH Coumarin production observed in the presence of H-ND compared to irradiation of Coumarin alone. In parallel, no •OH increase was observed for oxidized DND in the same conditions of irradiation. To sum up, coumarin model is a first step to explain the origin of the radiosensitization of H-ND and more generally to investigate the production of reactive species (as radicals or solvated electrons) at the hydrogenated diamond surface under illumination. [1] Grall, R. et al., A combination of hydrogenated nanodiamonds and -irradiation drive radiation-resistant cancer cells to senescence, Biomaterials 2015 [2] Sicard-Roselli, Cecile et al., A new mechanism for hydroxyl radical production in irradiated nanoparticle solutions, Small 2014

Resume : Multimodal imaging probes based on carbon nano-onions (CNOs) have emerged as a platform for bioimaging because of their cell-penetration properties and minimal systemic toxicity. [1-3] 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 their selective and rapid uptake in two different cancer cell lines without significant cytotoxicity is demonstrated. The localization of the functionalized CNOs in late-endosomes cell compartments is revealed by a correlative approach with confocal and transmission electron microscopy (see Figure). [4] Understanding the biological response of functionalized CNOs with the capability to target cancer cells and localize the nanoparticles in the cellular environment, will pave the way for the development of a new generation of imaging probes for future biomedical studies. [1] Yang, M. et al. Small 9, 4194 (2013). [2] Bartelmess, J. et al. RSC Adv. 5, 50253–50258 (2015). [3] Marchesano, V. et al. Nanomaterials 5, 1331 (2015). [4] Frasconi, M. et al. Chem. Eur J. 21, 1971 (2015).

Resume : One of the most important factors in tissue engineering is a cell scaffold. The cell scaffold is required to support adhesion, growth, and differentiation of cells of the desired phenotype. Cell morphology is also a critical consideration for multicellular tissue formations. Classically, the properties of biomolecules, including growth and transcription factors, have been investigated and demonstrated to regulate cell differentiation. Recent studies have also demonstrated that the use of 3D cell scaffolds in the absence of inductive biomolecules not only provides an appropriate surface but also suitable spaces for cell adhesion, growth, and morphological control. These 3D structures containing an appropriate surface for cell differentiation are typically required not only to construct a 3D platform but also to functionalize its surface. However, these substrates suffer the disadvantage of complex fabrication processes making the preparation of large-area scaffolds inconvenient. Carbon clusters have attracted significant attention including as potential materials for biological applications because of their biocompatibility. Because of their unique physicochemical properties, the sp2-hybridized graphitic structures of carbon clusters have exhibited significant applicability for use as cellular scaffolds in tissue engineering, including for cell adhesion, proliferation, and differentiation. Here, we present that cell scaffolds composed of highly aligned fullerene whiskers (FWs), can be used to control cell morphology, orientation and differentiation. These cell scaffolds were prepared by two different approaches; the Langmuir–Blodgett (LB) approach and Voltex-alignment approach. The aligned FWs cause elongation of deposited myoblast cells and induce cell differentiation to muscle cells. Our aligned FW substrate is made by a facile method of the LB approach or Voltex approach, and hence our substrate is a promising alternative to other recently reported cell scaffolds for large-scale tissue engineering.

Resume : Single-molecule fluorescence observation is an important technique to study molecular mechanism of biomolecules. However, it is frequently suffer from photobleaching and background autofluorescence originating from fluorescent materials pre-existing in living samples. Nitrogen vacancy centers (NVCs) in nanodiamonds have recently been attracting much attention as a new fluorescent probe. NVC is an atomic-sized defect paired with a nitrogen atom and the adjacent vacancy of a carbon atom in the diamond lattice. It is known that fluorescence from NVC-containing nanodiamonds is markedly stable in contrast to organic and semi-conducting fluorescent probes commonly used in cellular and in vivo observations. NVC exhibits neither photobleaching nor blinking, both of which are problems frequently encountered in current fluorescence imaging when conventional fluorescent probes are employed. A notable property is that the fluorescence from NVC is dependent on a spin degree of freedom in the ground states, and the fluorescence intensity can be manipulated by microwave irradiations in optically detected magnetic resonance. By using this property, we developed selective fluorescence detection technique and a rotational motion detection technique to analyze biomolecules. These features make nanodiamonds highly promising fluorescent probes for cellular and in vivo fluorescence imaging.

Resume : Doping of carbon nanoparticles with impurity atoms is central to their application. However, doping has proven elusive for very small carbon nanoparticles because of their limited availability and a lack of fundamental understanding of impurity stability in such nanostructures. We have shown that isolated diamond nanoparticles, extracted from chondritic meteorites, comprising only 400 carbon atoms, are capable of housing stable photoluminescent defect, namely the silicon vacancy (SiV). A novel composite material consisting of a photoluminescent nanodiamond (ND) core with uniform porous silica coatings was developed. This design intended for drug delivery applications allows simultaneous stable fluorescent imaging with high loading capacity of bioactive molecules. The ND key property, photoluminescence, is not quenched regardless of coating with thick silica layers. The high loading capacity for incorporation of active agents, provided by the introduced porous layer, is demonstrated by adsorption of a hydrophobic model drug to the composite particles. Techniques of super high spatial resolution, such as stimulated emission depletion microscopy and near-field scanning optical microscopy with aperture probe, were applied to detect individual luminescent diamond nanoparticles with the resolution exceeding diffraction limit.

Resume : Carbon Nano Onions (CNOs) have been probed with success for their possible implementation in the biomedical research field.[1] Functionalization of CNOs surface with fluorophores has been achieved by exploiting different strategies in order to maximize the nanomaterial’s fluorescence brightness in the cells.[1-4] In order to move a step towards possible applications of CNOs for in vivo imaging purposes, it is necessary to access the biologically relevant NIR emission window. In this communication we present a new BODIPY-based fluorophore specifically designed to endow CNOs of a bright fluorescence emission in this spectral window. The CNOs functionalized with this new BODIPY derivative display bright fluorescence emission since the fluorophore efficiency is poorly affected by the covalent attachment to the CNOs surface.[5] The results pave the way to further investigations of this nanomaterial-fluorophore combination for possible live bioimaging applications, e.g. for through-skin detection of cancerous lesions. References: [1] Yang, M. et al. Small 9, 4194–4206 (2013). [2] Bartelmess, J. et al. Nanoscale 6, 13761–13769 (2014). [3] Giordani, S. et al. J. Mater. Chem. B 2, 7459–7463 (2014). [4] Frasconi, M. et al. Methods Appl. Fluoresc. 3, 044005 (2015). [5] Bartelmess, J. et al. Chem-Eur. J. 21, 9727–9732 (2015).

Resume : Colloidal semiconductor quantum dots (QDs) make good candidates for applications in photovoltaics, optoelectronics and bio-imaging. For these purposes, broad spectral tunability and superior optical properties are required. Therefore direct bandgap materials are often employed. However, they’re toxic, scarce and/or (chemically) instable. For this reason, Si and Ge are studied as an alternative, but their optical properties are commonly inferior due to the indirect bandgap. This is reported to change upon surface termination with carbon chains, which effects the electronic structure due to a combined quantum confinement effect and formation of Si-C or Ge-C bonds at the surface. An enhanced radiative rate, broad spectral tunability and efficient fast emission have been observed for butyl-terminated Si QDs[1]. Here we compare their optical properties with those of butyl-terminated Ge as well as graphene QDs, by studying their spectrally- and time-resolved emission, and steady-state and induced absorption. The latter is done by using ultrafast transient induced absorption spectroscopy. The intraband transitions of free carriers generated by the pump pulse are probed over the whole visible range, providing a time-dependent evolution of absorption spectra. These findings provide new insights with respect to the possible absorption and emission mechanisms in surface terminated quantum dots, to further enhance their application potential. [1]K. Dohnalova et al. doi:10.1038/lsa.2013.3

Resume : Carbon dots (CDs) offer combined advantages of organic materials and semiconductor nanoparticles, can be synthesized by facile methods and can be easily (bio-)functionalized. Full-color CDs offer spectrally tunable emission through the visible range and broad absorption, interesting for many applications. Nonetheless, the exact origin of the tunable photoluminescence (PL) of these C-dots is not yet fully understood; there is evidence for quantum confinement in the carbon core, functional group related emission or a combination of both. These properties are difficult to study with ensemble spectroscopy techniques, as these yield averaged out properties in which information on individual QDs is lost. Therefore, we study CDs by single QD spectroscopy to obtain deeper understanding of the processes underlying the full-color emission of CDs and to explore the potential and limitations of this material. We show that full-color tunability can be achieved by introducing O and N containing functional groups [1] and that ensemble emission can be constructed from single C-dot contributions. Moreover our study indicates the presence of multiple emissive domains contained in the CD, meaning that color-tunability within individual CDs can be achieved. [1] H. Nie et al. Chem. Mater. 2014, 26, 3104-3112

Resume : Carbon materials, such as diamond powder, films, diamond-like carbon (DLC) films, and single-walled carbon nanotubes (SWNTs) are attractive materials and have been widely investigated because of their various unique electrical, thermal, biological and mechanical properties. Chemical modification of the surface of these materials is expected to lead to an improvement of their original properties while maintaining the bulk properties of carbon materials. To date, the modification of carbon surfaces with functional moieties has been studied by the treatment with toxic gas, plasma, hazardous condition and multi-step reactions because of their chemical stability of carbon materials. We have developed simple and useful processes for fabricating functional carbon materials modified with a variety of functionalities by chemical surface modifications. The introduction of the functional moieties such as fluorine-, oxygen-, and sulfur-containing functionalities and other organic functional groups on the surface of carbon materials by using photochemical and organochemical processes showed hydrophobicity, hydrophilicity, biomolecular attachment, tribological properties and metal attachment while maintaining the bulk properties of carbon materials.

Resume : Fluorescent diamond nanoparticles (FNDs) represent a key component in recent development of ultra-high precision optical resolution techniques. FNDs can accommodate nitrogen-vacancy (NV) centers – an extremely photostable crystal lattice defect emitting in near-infrared region. Electron transitions among NV quantum states can be influenced by very weak external electric or magnetic fields, which have been utilized for construction of various types of probes and nanosensors. For application of FNDs in biological systems and for achieving high target selectivity, a precise control of particles’ bionanointerface is urgently needed. Different synthetic approaches towards bioapplicable FNDs will be presented. Creation of different antifouling polymeric coatings on FNDs, their physico-chemical comparison, bioorthogonal modification with various (bio)molecules using click chemistry, and imaging of cancer cells using these conjugates will be shown.

Resume : Aggregates of detonation nanodiamond have long been of interest for their numerous potential applications; however, no size of detonation nanodiamond (DND) is perhaps more elusive, yet technologically important, than sub 10 nanometer (or “single-digit”) primary particles. Primary particles of DND have a number of potential applications including drug delivery, seeding in microelelctronics, polymer nanocomposites, and lubricants. Nevertheless, the challenge associated with obtaining these particle from the 200-300nm aggregates of purified detonation soot has made them too expensive for widespread use. Even after overcoming the initial challenge of obtaining the primary particles, they are still often limited in their use due to the random assortment of chemical functional groups found on their surface. Therefore, an additional challenge is to gain control over the ability to tailor the surface chemistry of the particles without sacrificing their size by promoting aggregation. A final challenge is to identify useful solvents where stability and size of the functionalized particles are preserved. Here we report our work in obtaining high yields of 5nm particles of DND, progress made toward functionalizing these particles with a number of useful chemical structures including: carboxyls, hydroxyls, amines, hydrophobic chains and the dispersion of these particles in a range of solvents such as DMSO, NMP, DMF, THF, Ethylene Glycol, Synthetic Oils, alcohols, and water.

Resume : We describe a fast and versatile method to functionalize high-quality graphene with organic molecules by exploiting the synergetic effect of supramolecular and covalent chemistry. Towards this goal, we designed and synthesized a molecule comprising a long aliphatic chain and an aryl diazonium salt. These molecules are self-assembled from solution onto CVD graphene, forming an ordered monolayer. Then, the sample is transferred into water, to hinder both the structural reorganization within the monolayer and the molecular desorption. An electrochemical stimulus is used to transform the diazonium head-group into a radical capable of grafting covalently to graphene. During covalent grafting in water the molecules retain the ordered packing formed upon self-assembly before the covalent linkage. Our 2-steps approach is characterized by the independent control over the processes of immobilization of molecules on graphene and their covalent tethering, enabling massive and fast (t<10 sec) covalent functionalization of graphene. This strategy is highly versatile: it can be operated using different solvents and on many carbon-based materials including graphene deposited on silicon, plastic, quartz, as well as glassy carbon and highly oriented pyrolytic graphite.

Resume : Boron doped diamond has been utilized as an electrode material to construct an electric double layer capacitor (EDLC) as well as an electrode support to form a pseudocapacitor. In a 1.0 M NaSO4 solution, the capacitance of diamond EDLC is in the range of 3.6-7.0 µF cm-2, comparable with those of EDLCs based on other carbon materials. During a charge/discharge process for 1000 cycles at a scan rate of 100 mV s-1, the capacitance only decreases 5%, indicating high sta-bility and a long life-time of such an EDLC. To improve the capacitance of diamond EDLCs, di-amond was coated with a MnO2 film to construct a pseudosupercapacitor. The MnO2 films were electrodeposited at a constant potential of 0.9 V vs. Ag/AgCl in 0.2 M MnSO4 solution. The mass of MnO2 deposited per unit area, so-called the area density, calculated from the deposition charge, was controlled via the deposition time. The MnO2 films were characterized using various tech-niques like SEM, XPS, and Raman spectroscopy, etc. In a 1.0 M NaSO4 solution, the capacitance of the MnO2/diamond based pseudosupercapacitor rises with an increase of the mass of MnO2 on diamond. Its maximum capacitance was found to be reached at a MnO2 area density of 24 µg cm-2. The capacitance obtained from voltammetry is 384 µF, or 326 F g-1 at a scan rate of 10 mV s-1, which is comparable with the value of 406 µF, or 349 F g-1, obtained from charge/discharge pro-cess at a current density of 3 A g-1 in the potential range 0 to 0.8 V. The capacitance was reduced by 34% after 1000 subsequent charge/discharge cycles carried out at a scan range of 100 mV s-1. The comparison of the performance of the MnO2/diamond pseudosupercapacitor with that of those pseudosupercapacitors based on MnO2 and other carbon materials indicates that diamond could be suitable for electrochemical supercapacitor applications.

Resume : Nanodiamond (ND) particles have recently emerged as a key platform for many sectors of nanoscience and nanotechnology due to their outstanding mechanical performance, biocompatibility and distinctive optical properties, a combination of assets not often met in the nanoworld. Optically active NDs remain one of the most popular research topics mainly due to the photoluminescent properties of crystallographic defects in the diamond lattice, referred to as color centers. In this talk, the optical properties of ND particles as well as related current and perspective applications will be discussed. Recently our group succeeded in large scale production of fluorescent NDs containing nitrogen-vacancy (NV) color centers in hundreds of grams batches. Production of fractions of ND-NV with median sizes ranging between 10 and 100 nm was achieved. The content of NV centers in micron-sized particles and in NDs as a function of irradiation dose and particle size will be reported. Relative brightness of nanoparticles of different sizes and surface termination will be also summarized. ND-NV functionalized with bioligands have perspectives as highly photostable and non-toxic fluorescent labels in life science applications. NDs containing color centers absorbing UV light in combination with the high refractive index of diamond providing extensive UV light scattering are also appealing for use in healthcare products such as sunscreens. Acknowledgment: NIH SBIR Phase I and Phase II Contract HHSN268201500010C.

Resume : In this work we report on the growth and characterisation of nanodiamond thin films grown on {111} Si substrates using 2,2-divinyladamantane (DVA) as a chemical precursor. Earlier studies of similar growth attempts have led to the formation of sparse nanocrystalline islands[1–4]. Here we demonstrate nucleation through the use of a low temperature incubation step after grafting the DVA to the silicon surface. The covalent attachment of DVA was done by using a variation of the process detailed in Giraud et al[1]. The silicon surface was first cleaned with hydrofluoric acid to remove the native oxide, coated with DVA, and then immediately placed inside a chamber. The chamber was repeatedly flushed with nitrogen to get rid of any oxygen. After flushing the chamber, the samples were illuminated with UV (180-370nm) radiation in a nitrogen atmosphere for 1 hour. To remove the excess DVA, the samples were rinsed with ethanol and DI and then sonicated twice in dichloromethane. The coated samples were subsequently placed in a Seki 6500 series CVD system and left to dry in vacuum (<5e-6 mbar) for more than 12 hours prior to growth. The coated samples were then exposed to low intensity plasma and temperatures of 250 C for varying amounts of time from 5 to 60 mins. This incubation phase of growth was carried out to prevent sublimation and allow the adamantane molecules to form nanodiamond seeds. Upon completion of this incubation period the temperature of the sample was raised to 900 C by increasing the power density of the plasma. The resulting films were characterized using Raman spectroscopy and the surface texture was recorded using scanning electron microscopy, while the presence of seeds on an incubated wafer was confirmed using atomic force microscopy. References [1] A. Giraud, T. Jenny, E. Leroy, O.M. Küttel, L. Schlapbach, P. Vanelle, and L. Giraud, J. Am. Chem. Soc. 123, 2271 (2001). [2] R.N. Tiwari and L. Chang, J. Appl. Phys. 107, 103305 (2010). [3] R.N. Tiwari, J.N. Tiwari, and L. Chang, Chem. Eng. J. 158, 641 (2010). [4] Y.-C. Chen and L. Chang, RSC Adv. 3, 1514 (2013).

Resume : The tailoring of new grafts and scaffolds by nanostructuring sp2 and sp3 coordinated carbons is presently giving an edge to biomedical applications, going from tissue engineering and generation of artificial organs to fabrication of prosthetic and packaging systems .By the combined use of several CVD growth techniques, of MW-RF plasma sculpturing, and of wet chemistry processes, we produce differently shaped substrates and functionalized surfaces for the engineering of nanoC-based platforms.In particular, some relevant examples of materials and multivalent architectures characterized by biocompatibility and long-time reliability are :for C-sp2; few-layers graphene assembled in shaped platelets; high density arrays of conical nanostructures protruding from glassy carbon surfaces; dendrimers with various shape/branching; arrays of carbon nanotubes on selected areas of patterned substrates : for C-sp3 ; shaped aggregates of nanodiamond grains from colloidal suspensions; CVD-grown nanocrystalline diamond films; arrays of 1D nanostructures (nanorods, whiskers, nanopillars,nanocones) obtained by plasma etching of diamond films . The shaping of C materials in pre-definite forms enables to fabricate scaffolds tailored for specific tissue growth, whereas the control of surface chemistry offers an added value for interactions with biological systems. Some strategies developed for nanocarbon-based systems will be illustrated, along with their bioapplications.

Resume : Diamond nanoparticles or nanodiamonds (NDs) produced by various synthesis methods have attracted a lot of attention over the last years. Because their potential applications are numerous, studies of these materials aim to understand, control and tailor their production as well as their physical and chemical properties which are given by the combination of an inert diamond core with a surface rich in functional groups [1]. Indeed it is generally accepted that ND crystallites are composed of a diamond core of a few nanometres in diameter, partially or completely covered by a thin layer of graphitic and / or amorphous carbon, and bearing carboxyl-, hydroxyl and carbonyl functionalities on the surface. Raman scattering is one of the spectroscopic methods that can used for the characterization of those nanodiamonds. Focusing on ND with particle sizes lower than about 20 nm, the Raman spectra of those nanoparticles are usually composed of a broadened and downshifted first-order diamond Raman signal and a broad line peaking in the 1580 – 1650 cm-1 wavenumber range. While some works have suggested that this broad peak seems to be sensitive to the NDs surface chemistry, the assignment of this signal is still unclear [1-4]. Furthermore, other broad features may also be observed in the 300-1000 cm-1, 1000-1350 cm-1 and 2000-3600 cm-1 ranges. As attempt to clarify the origin of these signals, we have monitored changes in the spectra of different NDs, including HTHP and detonation NDs, with different surface terminations. Various visible as well as UV excitation lines were used for the analysis. We will also address some experimental problems that can be encountered during the analysis of these nanoparticles. In particular, using excitation in the deep UV range, analysis conditions (atmosphere and incident power) must be chosen carefully. References 1. V.N Mochalin, O Shenderova, D. Ho and Y Gogotsi, Nat. Nanotechnol. (2012) 7, 11 2. V. Mochalin, S. Osswald and Y Gogotsi, Chem. Mater. (2009) 21, 273 3. S. Osswald, G. Yushin,.V. Mochalin, S.O. Kucheyev and Y. Gogotsi, J. Am. Chem. Soc. (2006) 128, 11635 4. M. Mermoux, A. Crisci, T. Petit, H.A. Girard and J.C. Arnault, J. Phys. Chem C, (2014) 118, 2341

Resume : Graphene represents a unique platform for efficient fluorescence quenching due to its broadband absorption permitting energy transfer across the entire visible spectrum. Here, we transfer large area, single-layer CVD graphene on healthy and diseased kidney tissues taken from patients through biopsies. To avoid bio-chemical changes of tissues induced by heating during the transfer, a new procedure applicable at room temperature is developed based on a collodion solution. Fluorescence intensity measurements performed at the same positions before and after the graphene transfer using three visible lasers for excitation (457, 532, 660 nm) confirm the decrease of the fluorescence signal originating from the tissues when in intimate contact with graphene. The reduced fluorescence background along with the graphene-enhanced Raman scattering (known as the GERS effect) lead to pronounced Raman peaks enabling a detailed structural characterization of the tissues. Mapping Raman Spectroscopy reveals clear differences between healthy and diseased kidney tissues in the intensity of several Raman peaks, which can be used for fast, in vitro, high accuracy diagnosis. Moreover, the changes in the surface chemistry of graphene caused by the tissues are addressed for its further functionalization. Our approach can also be applied to other biological samples with intrinsic fluorescence paving the way for Raman imaging using visible lasers in biomedical applications.

Resume : To vary interfacial properties, electrochemical grafting of graphene nano platelets (GNP) with 3,5-dichlorophenyl diazonium tetrafluoroborate (aryl-Cl) and 4-nitrobenzene diazonium tetrafluoroborate (aryl-NO2) was realized in a potentiodynamic mode. The covalently bonded aryl layers on GNP were characterized using atomic force microscope and X-ray photoelectron spectroscopy. Electrochemical conversion of aryl-NO2 into aryl-NH2 was conducted. The voltammetric and impedance behavior of negatively and positively charged redox probes (Fe(CN)63-/4- and Ru(NH3)62+/3+) on three kinds of aryl layers grafted on GNP reveal that their interfacial properties are determined by the charge states of redox probes and reactive terminal groups (-Cl, -NO2, -NH2) in aryl layers. On aryl-Cl and aryl-NH2 garted GNP, selective and sensitive monitoring of positively charged lead ions as well as negatively charged nitrite and sulfite ions was achieved, respectively. Such a grafting procedure is thus a perfect way to design and control interfacial properties of graphene.

Resume : Lithium doped NiO nanofibers were synthesized using electrospinning followed by calcinations. The morphology, crystal structure, and electrochemical activities of these nanofibers were characterized respectively with scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), and electrochemical techniques. Electrocatalytic oxidation of glucose was found on these nanofibers in 0.1 M NaOH. The catalytic oxidation current is linear with the concentration of glucose in the range of 0.5 to 278 μM. The detection limit was calculated to be 0.1 μM. Lithium doped NiO nanofiber is thus a potential electrode material for the construction of non-enzymatic glucose sensor.

Resume : Recently, the antibiotic pollution has gained great attentions in the food and environment fields. Due to the novel properties of carbon nanomaterials, a large variety of electrochemical methods have been developed for antibiotics measurement. However, how to avoid the homologue interferences is a great challenge to these methods. In this work, a graphene-silver nanoparticles (Ag NPs) based electrochemical aptasensor was prepared and used for sensitive and selective measurement of the chloramphenicol antibiotic sucessfully. The carbon nanocomposite was prepared through in situ deposition of Ag NPs on the surface of graphene oxide followed by hydrothermal reduction. After electrode modification with graphene-Ag NPs followed by the aptamer immobilization, the resulting aptasensor was obtained and used to incubte the sample solution containing chloramphenicol. Based on electrocatalytic reduction of the chloramphenicol quantiatively captured on the electrode surface, sensitive electrochemical signal was produced for signal tracing, thus leading to the successful development of a novel method for the chloramphenicol measurement. Due to the excellent electrocatalytic property of the graphene-Ag NPs nanocomposite and the specific aptamer recognition, excellent analytical performance of the method was achieved for selectively detecting chloramphenicol residues in real samples.

Resume : Abstract: Since thin layer 2D materials have been attracting enormous interest, various processes have been investigated so far to obtain these materials efficiently. In view of their practical applications, the most desirable source is the pristine bulk material with stacked layers such as pristine graphite. On their exfoliation, we have many options in terms of conditions such as wet or dry, with or without additive, and kind of solvent. In this context, we have found versatile exfoliant, hexahydroxytriphenylane, which works efficiently for exfoliation of typical 2D materials, graphene, MoS2, and h-BN, in both wet and dry processes using sonication and ball-milling, respectively, in aqueous and organic solvents. As for graphene, stable dispersions with relatively high concentration (up to 0.28 mg/mL) in water and tetrahydrofuran were obtained from graphite in presence of hexahydroxytriphenylene by wet process using bath sonication and via dry process using ball-milling. Especially, most of graphite was exfoliated and dispersed as thin layer graphene in both aqueous and organic solvents through ball-milling even at large scale (47 - 86% yield). In addition, the exfoliant can be easily removed from the precipitated composite by heat treatment without disturbing the graphene structure. Bulk MoS2 and h-BN were also exfoliated in both wet and dry processes. As in graphene, MoS2 and h-BN dispersions of high concentrations in water and DMF were produced in high yields through ball-milling.

Resume : We report on the application of pristine graphene as a drug carrier for phototherapy (PT). The loading of a photosensitizer, chlorin e6 (Ce6), was achieved simply by sonication of Ce6 and graphite in an aqueous solution. During the loading process, graphite was gradually exfoliated to graphene to give its composite with Ce6 (G−Ce6). This one-step approach is considered to be superior to the graphene oxide (GO)-based composites, which required pretreatment of graphite by strong oxidation. Additionally, the directly exfoliated graphene ensured a high drug loading capacity, 160 wt %, which is about 10 times larger than that of the functionalized GO. Furthermore, the Ce6 concentration for killing cells by G−Ce6 is 6−75 times less than that of the other Ce6 composites including GO−Ce6.

Resume : Nanodiamond holds great potential for biomedical applications, in particular, as drug carrier and imaging probes. For these purposes, nanodiamond are required to be functionalized to add the requisite properties such as enough dispersibility and stability under physiological conditions, and maximal targeting and stealth character. In this talk, I will present surface chemistry of nanodiamond including polyglycerol functionalization, further derivatization and their characterization based on organic chemistry, and biomedical application of the chemically functionalized nanodiamond.

Resume : We have been developing host-guest methodology for separation of single-walled carbon nanotubes (SWNTs). Tweezer- and caliper-shape host molecules, designated as diporphyrin nanotweezers and nanocalipers respectively, consist of two chiral porphyrins and rigid spacer in between. They discriminate handedness, diameter, roll-up index, and even metalicity. Since the first report about optically active SWNTs [1], we have improved selectivity of the host molecules by changing the angles and distances of the two porphyrins [2-7]. 1. X. Peng, N. Komatsu,* S. Bhattacharya, T. Shimawaki, S. Aonuma, T. Kimura, A. Osuka, Nature Nanotechnology, 2, 361 (2007) 2. G. Liu, F. Wang, S. Chunchaiyakul, Y. Saito, A. K. Bauri, T. Kimura, Y. Kuwahara, N. Komatsu,* J. Am. Chem. Soc., 135, 4805 (2013) 3. F. Wang, K. Matsuda, A. F. M. M. Rahman, X. Peng, T. Kimura, and N. Komatsu,* J. Am. Chem. Soc., 132, 10876 (2010) 4. X. Peng, N. Komatsu,* T. Kimura, A. Osuka, J. Am. Chem. Soc., 129, 15947 (2007) 5. G. Liu, Y. Saito, D. Nishio-Hamane, A. K Bauri, E. Flahaut, T. Kimura, N. Komatsu,* J. Mater. Chem. A, 2, 19067 (2014) 6. G. Liu, A. F. M. M. Rahman, S. Chaunchaiyakul, T. Kimura, Y. Kuwahara, N. Komatsu,* Chem. Eur. J., 19, 16221 (2013) 7. X. Peng, F. Wang, A. F. M. M. Rahman, A. Bauri, and N. Komatsu,* Chem. Lett. (highlight review), 39, 1022 (2010) 8. F. Wang, K. Matsuda, A. F. M. M. Rahman, T. Kimura, and N. Komatsu,* Nanoscale, 3, 4117-4124 (2011). 9. A. F. M. M. Rahman, F. Wang, K. Matsuda, T. Kimura, and N. Komatsu,* Chem. Sci., 2, 862-867 (2011) [highlighted at the inside front cover]. 10. G. Liu, F. Wang, X. Peng, A. F. M. M. Rahman, A. K. Bauri, and N. Komatsu,* Handbook of Biomedical Applications of Carbon Nanomaterials; K. M. Kadish and F. D'souza, Eds.; World Scientific: vol. 3, pp. 203-232 (2012).

Resume : For biomedical in vivo applications of nanocarbons as drug carriers, they have to be dispersed well in a physiological environment. Recently, we have found that polyglycerol (PG) grafted onto diamond and iron oxide nanoperticles, and afforded very good hydrophilicity and biocompatibility. In this study, we applied this methodology to synthesize PG functionalized graphene (G-PG) and SWNTs (SWNT-PG), and employed them for photodynamic therapy (PDT) after a photosensitizer was loaded on their hydrophobic surface. Since we exfoliated graphene in water from graphite under sonication in the presence of hydroxytriphenylene, the resulting graphene was functioned with PG after removal of the exfoliant. A photosensitizer, chlorin e6 (Ce6), was loaded on the hydrophobic surface of G-PG through π-π and hydrophobic interactions. The obtained G-PG-Ce6 exhibited good aqueous dispersibility. After incubating SKOV3 cells in the presence of G-PG-Ce6 under light irradiation, the G-PG-Ce6 complex showed remarkable PDT effect as compared to Ce6 itself. In the case of SWNTs, they were functionalized with PG after cutting and Ce6 were loaded on them. The resulting SWNT-PG-Ce6 also exhibited similar photodynamic activity.

Resume : Nanodiamond (ND) has received considerable attention due to their chemical inertness, biocompatibility and noncytotoxicity, all of which make it suitable for biomedical applications. However, surface functionalization of ND is a key step to realize in vivo applications such as imaging probe and drug carrier. In this study, we began with ND with 30 nm size to be functionalized with polyglycerol (PG) through ring-opening polymerization of glycidol. Dispersibility of the resulting ND-PG improved significantly as compared with the previous ND-PG we synthesized, because we efficiently introduced much more number of oxygen-containing functional groups through pretreatment with sonication. Next, amino group was introduced at the hydroxyl groups of PG through multistep organic transformation (-OH  -OTs (tosylate)  -N3  -NH2) to give ND-PG-NH2. Finally, the ND-PG-NH2 was covalently conjugated with verteporfin (VP) through amide linkage. The resulting ND-PG-VP showed good dispersibility in a physiological environment in spite of the hydrophobic nature of VP. VP is expected to work as an anti-cancer drug as well as a photosensitizer in photodynamic therapy. Application of ND-PG-VP to cancer therapy is now in progress.

Resume : A multilayer CdS-DNA biofilm was fabricated on the graphite electrode surface via layer by layer (LBL) self-assembly technique. The morphological structure and photoelectrochemical property of the as-prepared biofilm was characterized by scanning electron microscopy (SEM) and photocurrent measurement. The results raveled that hybrid film preserved both visible light photoelectrochemical of CdS and biochemical activity of DNA. Moreover, methylene blue (MB) was adsorbed on the biofilm due to the interaction between MB and DNA which was studied using UV-vis absorption spectroscopy. As a result, the fabricated biofilm showed enhanced photocurrent response toward (MB) under visible-light excitation. The photoelectrochemical current was linearly proportional to the concentration of MB in the range of 3.0×10-8 to 3.0×10-6 mol L-1, with a detection limit of 1.4×10-8 mol L-1. The multilayer CdS-DNA biofilm modified graphite electrode provides a novel visible-light photoelectrochemical biosensor.

Resume : Inquiring high-resolution image of model bacteria is important step for researching fundamentals or applications of molecular biology, bacteriology, or biomedical engineering. Currently, there are few ways to get high resolution image: confocal microscopy, transmission electron microscopy(TEM), and scanning electron microscopy(SEM). Among them, SEM imaging is most intuitive method for observing three dimensional surface images of small cells. However, the cell should be dehydrated and stained with metallic component to prevent osmotic lysis and electrical charging problem. This process will sterilize the bacterial cells and replace original component of pristine cells. Recent studies have reported that functioning cells, either bacterial or mammalian, can be observed in TEM, with using silicon nitride based liquid cell. However, due to the intrinsic penetration depth of transmitted electron, detailed imaging of cell is nearly impossible with this method. Covering specimen with graphene can provide high-resolution image, providing physically insulated system. Usually this encapsulation technique was conducted on inorganic nanomaterials, but recent research shows that proteins and virus can also encapsulated and imaged in TEM. In this research, several kinds of bacteria are veiled with single layer graphene to prevent lysis and electrical charging in high vacuum while preserve moisture contents. Also, cell viability is determined with cell reproducibility and live/dead kit.

Resume : In this work, a highly sensitive and selective electrochemical sensor for 4-chlorophenol was constructed by molecularly imprinted polymer (MIP) and poly(diallyldimethylammonium chloride) (PDDA) functionalized graphene (PDDA-G). PDDA-G obtained from the reduction of graphene oxide facilitated the electron transfer and enlarged the surface of electrode. The imprinted polymer was prepared by bulk polymerization and served as a recognition element in the construction of an electrochemical sensor for 4-Chlorophenol (4-CP). The advantages of the above two modification materials were combined in this imprinted sensor, which exhibited outstanding selectivity, high sensitivity, rapid response time and ease of construction. The chemical structures and morphologies of the imprinted films were characterized using infrared spectroscopy and scanning electron microscopy. The parameters affecting the analytical performance were investigated. Under optimized conditions, the sensor showed a wide linear response in the range of 8×10-7 to 1.0 × 10−4 mol•L−1 with a detection limit of 3×10-7 mol•L−1. The sensor was successfully applied to the analysis of 4-CP in water samples.

Resume : Graphene/CdS (GR-CdS) nanocomposite was synthesized via a low-temperature water-phase method. As GR-CdS nanocomposite-enhanced interface could significantly improve the voltammetric responses of the modified glassy carbon electrode, we constructed various electrochemical sensors for the sensitive determination of pharmaceuticals and pollutants. We found that the GR-CdS modified electrode realized the selective and simultaneous detection of catechol, hydroquinone and resorcinol. Using a GR-CdS modified electrode, the degradation of hydroquinone in the presence of catechol and resorcinol was selectively monitored and investigated. On the other hand, we observed that GR-CdS nanocomposite improved the immobilization amount of DNA on the electrode surface and promoted the electron transfer of DNA. Thus, DNA was immobilized on GR-CdS modified electrode to fabricate electrochemical DNA biosensors for determination of various pharmaceuticals such as kanamycin sulfate and phenformin hydrochloride which interacted with DNA. Under optimal conditions, the GR-CdS-based DNA sensors were successfully employed to monitor the degradation of kanamycin and determine the content of phenformin in commercial phenformin tablets.

Resume : The capabilities of plasma assisted technique based on electrical discharge in liquid (EDL) for synthesis of nanoscale carbon particles have been examined. The advantages of an electrical discharge method for the synthesis of nanoparticles (NPs) include a possibility of controlling the parameters of the final product by varying discharge conditions, ecological safety and scalable synthesis process. The experimental procedure and apparatus for a preparation of NPs by the electrical discharge method have been described earlier [1]. For the synthesis of carbon NPs spark discharge between two graphite electrodes immersed into octane was used. Primary control of composition and structure of the products formed was carried out by recording their Raman, IR, absorption and luminescence spectra. Optical absorption spectra of as-prepared suspension exhibited a broad absorption band in the UV spectral range. Raman spectroscopy indicated the gtaphitic-like structure of the synthesized NPs. The peak at 1597 cm-1 related to sp2-bonded graphitic carbon was observed. The TEM investigation showed separate spherical particles with average size 2.5 nm. Sometimes they were partly agglomerated. The peak position of PL spectrum was found to be gradually shifted from 330 nm to 515 nm with changes in excitation wavelength from 250 nm to 450 nm. Carbon NPs with sizes below 10 nm having size selective luminescence are promising material for the biomedical applications. 1. V. S. Burakov et al. Rus. J. Gen. Chem. 85 (5), 17 (2015)

Resume : A class of novel core-shell nanocrystals comprising of dodecahedron Au and Ag (Au12@Ag) are synthesized as molecular tags sensitive electrochemical immunoassay (prostate specific antigen, PSA, as a model analyte) on AuNPs–GO–CS cryogel immobilized onto nano-Ag sensing plat-form. To construct such a molecular tag, a certain amount of cetyl trimethyl ammonium bromide (CTAB) , HAuCl4 solution and potassium borohydride (KBH4) were used to form rhombic-dodecahedral gold nanocrystal cores, and aqueous mixture of the surfactant CTAB, polyhedral Au nanocrystals, AgNO3, and ascorbic acid was made for 30 min to enable the formation of the core–shell nanoparticles, which were used for the label of anti-PSA conjugates. Graphene oxide (GO) as a good electrical conductivity electrod meterials with a layered structure, provided more attachment sites for nano gold. Thus, the formation of AuNPs–GO–CS cryogel not only has good electrical conductivity, but also has good biocompatibility, as well as large specific surface area. In the presence of analyte PSA, the sandwich-type immunocomplex was formed on an anti-PSA/ AuNPs–GO–CS /Ag-modified glassy carbon electrode by using anti-CEA/Au12@Ag as detection antibodies. A sandwich-type immunoassay format was employed for determination of PSA by using the decrease of the difference pulse voltammetry (DPV) silver peak current resulted in immunocomplexes. Under optimal conditions, the developed immunoassay displayed a wide linear range from 1.0×10-6 ng/mL to 20.0 ng/mL toward PSA standards, the detection limit of is 3.2×10-7 ng/mL (S/N=3). The precision, selectivity and stability were acceptable. Keywords：immunoassay; dodecahedron Au–Ag Core–Shell nanocrystals (Au12@Ag); AuNPs–GO–CS; prostate specific antigen(PSA).

Resume : Nanoparticles are highly attractive materials due to their size-dependent properties and large surface area. Exploiting these phenomena has potential wide-ranging applications including, sensing, imaging, drug delivery and therapy.1–3 Synthesised nanoparticles typically are coated with a ligand shell that confers electrostatic or steric stability. Tailoring nanoparticles for specific applications requires subsequent surface functionalisation which is usually achieved by covalent or non-covalent functionalisation.1 One of the main challenges encountered in nanoparticle functionalisation is to control the arrangement of different molecules at the surface. One solution to overcome this challenge is to use multi-component reactions that co-localise different functional molecules.4,5 In this communication, we report our findings on the functionalization of different families of carbon nanoparticles using a multi-component reaction to localise fluorophores, recognition molecules and stabilising ligands at the nanoparticle surface. The methodology used and full characterisation of this carbon particles will also be described. References: 1. V. Biju, Chem. Soc. Rev., 2014, 43, 744–764. 2. F. R. Baptista, S. a. Belhout, S. Giordani, and S. J. Quinn, Chem. Soc. Rev., 2015, 44, 4433–4453. 3. J. Bartelmess, S. J. Quinn, and S. Giordani, Chem. Soc. Rev., 2015, 44, 4672–4698. 4. M. C. Pirrung and K. Das Sarma, J. Am. Chem. Soc., 2004, 126, 444–445. 5. T. J. Sørensen, M. Tropiano, O. a Blackburn, J. a Tilney, A. M. Kenwright, and S. Faulkner, Chem. Commun., 2013, 49, 783–785.

Resume : Titanium dioxide (TiO2), a metallic nanoparticle has been widely used in domestic, cosmetic products and waste water treatment. After use, the mentioned nanoparticles are ultimately released to aquatic environments via bathing and sewage effluents leading to increased chances of nanoparticle exposure to human and ecosystems. TiO2-based nanoparticles induce production of reactive oxygen species (ROS), which create a redox imbalance. This leads to the physiological effect which is known as oxidative stress. Indicators of oxidative stress include changes in activity of antioxidant enzymes, levels of antioxidant molecules, damaged DNA bases, protein oxidation products, and lipid peroxidation products. In order to limit the transportation of ROS from the TiO2 surfaces into the gas and aqueous phase, in this contribution we present new photoactive TiO2-MWCNT nanocomposites with antioxidant modified surfaces, which can capture ROS species. The TiO2-MWCNT nanocomposites were surface functionalized by using laccase as catalyst to attach gallic acid polymerized molecules on the nanocomposite surface. Structure and surface functionalization was investigated by X-ray, infrared and UV-vis diffuse reflectance spectroscopy analysis. The antioxidant activity was analysed using 2,2-azino-bis(3-ethylbenzothiazoline-6-sul- phonic acid) and photocatalytic activity toward the liquid-phase degradation of methylene blue in aqueous solution under both UV and visible light irradiation. Acknowledgment: This research was supported by the Slovenian Research Agency (post-doctorate project, grant no. Z2-5493).

Resume : 1-[3-(N-cytimine)propyl]-3-vinylimidazolium tetrafluoroborate ionic liquid [(Cyt)VIMBF4] was successfully synthesized and characterized. The aforementioned ionic liquid was employed as a functional monomer to fabricate α-fetoprotein imprinted interface on a glassy carbon electrode (GCE) modified with gold nanoparticles (GNs). Firstly, gold nanoparticles were electrochemically deposited onto GCE surface. Then, (Cyt)VIMBF4 ionic liquid was self-assembled onto GNs/GCE surface as anchoring sites for the imprinted film. After that, using (Cyt)VIMBF4 ionic liquid as functional monomer, ethylene dimethacrylate as crossing linker, ammonium persulfate and N,N,N′,N′-tetramethylethylenediamine as initiator and α-fetoprotein (AFP) as template, a molecularly imprinted sensor was prepared through in-suit polymerizing. The sensing performance of the imprinted sensor was thoroughly investigated by using cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy. The results demonstrated that the imprinted sensor shows high specificity and sensitivity towards AFP. Acknowledgments The authors gratefully acknowledge the financial supports from National Natural Science Foundation of China (No.21275166) and the Natural Science Foundation of Hubei Province (No. 2015CFA092).

Resume : We present characterization and fabrication processes for nanocrystalline carbon (NCC) thin films. Deposition is done by unbalanced magnetron sputtering and typical film thicknesses are from tens of nanometers to several micrometers. Film characterization is done by electrical, spectroscopic and cell growth experiments. NCC has graphene-like sp2 bonded carbon islands in diamond-like sp3 bonded carbon matrix. The presence of sp2-islands are responsible for electrical conductivity, which can be verified with 4-point probe measurements. The sp2/sp3 bond ratio is confirmed with Raman-spectroscopy. NCC has many common properties with other carbonaceous materials like high hardness and chemical inertness. NCC can be patterned with RIE and ICP-RIE configurations, as we have demonstrated in our experiments with etch rates up to 40 nm/min by O2 + SF6 RIE process. We utilize the NCC etching processes for fabricating microelectrode arrays. Two types of electrodes were made: pure carbon and carbon contact pads with metal wires. The NCC multielectrode arrays are intended to be used for neurobiological experimentation to study neuronal maturation and signaling. The motivation for these applications is that carbon materials, especially carbon nanotubes, have been shown to be a very promising material for neuron-electrode interfacing. Experiments with rat hippocampal neurons reveal that the NCC film leads to enhanced neuronal maturation.

Resume : 1-[(3-N-pyrrol)propyl]-3-decyl-imidazolium tetrafluoroborate ionic liquid was synthesized and characterizaed with NMR and mass spectroscopy. The obtained ionic liquid was used as a functional monomer to fabricate a polymerized ionic liquid film electrode. The polymerized ionic liquid film electrode was characterized with scanning electron microscope and eletrochemical impedance spectroscopy. Electrochemical behavior of butylated hydroxyanis at the polymerized ionic liquid film electrode surface was investigated using voltammetry. It was found that the oxidation peak current of butylated hydroxyanis was significantly improved in the presence of polymerized ionic liquid film. A voltammetric method for butylated hydroxyanis determination was developed with high sensitivity and selectivity. The oxidation peak current was linearly related to butylated hydroxyanis concentration in the range from 2.0×10-8 to 5.0×10-5 molL-1. The detection limit was calculated to be 2.01×10-9 molL-1. Standard addition recovery experiments show that the sensor has good accuracy.

Resume : In recent years there is an extensive interest in diamondoids due to their successful application in diverse fields of nano- and biotechnology which rely on the physical and chemical properties imparted by their unique (cage-like) structure. In our study, adamantylamine (ADMA), an adamantane derivative with a covalently attached amino group, was intercalated into two types of layered matrices, graphene oxide (GO) and laponite (Lap) clay. Two case studies were conducted in biomedicine (antiproliferative agents in cells ) and environmental remediation (removal of organic pollutants from aqueous solution). The hybrid nanomaterials obtained by intercalation of ADMA into Lap and GO are capable of adsorbing significant quantities of organic pollutants, which entails a significant potential for environmental remediation. Additionally, the hybrid nanostructures were investigated for their cytotoxicity against one cancer cell line and one normal cell line. The findings revealed that Lap/ADMA and GO/ADMA presented improved cytotoxic activity on A549 cancer cells, whilst the cytotoxicity towards MRC-5 cells (normal cells) is maintained or only slightly increased as compared to Lap and GO, respectively.

Resume : Nanodispersed graphite oxide (GO) powder has been synthesized using graphite powder as precursor by modified Hammer’s method. Raman scattering and FTIR characterization prove that powder composed by oxidized few-layer graphene sheets. Zinc acetylacetonate was used as ZnO precursor. Ethanol solutions of grapheme oxide nanodots and zinc acetylacetonate were ultrasonically mixed and boiled at 78 C. Suspension was spincoated on silicon wafer and dried. Some of the samples were further annealed in flow of dry or wet nitrogen. The effect of graphene oxide dispersion, concentration of zinc acelytacetonate and annealing conditions on the structure and morphology of ZnO:GO nanocomposite was analyzed by Raman scattering, FTIR and photoluminescence spectroscopy. Preliminary results on the antibacterial properties of the nanocomposite will be presented as well.

Resume : Chemical modification of the hydrophobic fullerene C60 yielded numerous water-soluble adducts exhibiting a variety of biological activities [1], in particular, antiviral properties. We synthesized previously a wide range of polycarboxylic derivatives of [60]fullerene using well-established Friedel-Crafts arylation method [2] and chlorofullerene C60Cl6 as a precursor. Some correlations between the antiviral properties of the compounds and their chemical structure were revealed. It was noticed that increase in the number of carboxylic groups results in enhancement of the activity of fullerene derivatives against influenza viruses, HIV and herpes viruses. In the present work we focused on preparation and characterization of [60]fullerene derivatives comprising 10 carboxyl groups. Symmetrical dimethyl 2,2'-(1,4-phenylenebis(oxy))diacetate was used as a reagent for functionalization of C60Cl6 to achieve the best selectivity of the reaction. Contrary to our expectations, we obtained five main products which were isolated by flash chromatography on silica and preparative HPLC. The molecular compositions and structures of all compounds were proved by ESI-MS, 1H, 13C, and 2D NMR spectroscopy. The synthesized water-soluble fullerene derivatives represent good model compounds for establishing important correlations between their molecular structures and antiviral activity. 1. R. Bakry et al., Int. Journal Nanomed., 2007, 2, 639; 2. O. A. Troshina et al., Org. Biomol. Chem., 2007, 5, 2783

Resume : Spiral carbon nanoparticles (spiroids) are relatively new types of nanoclusters with the unique geometry, which might be very prospective for possible applications ranging from hydrogen storage for transport and related energy applications to drug delivery for biochemistry and medicine. In this paper we use ab initio Car-Parrinello method for analysis of capability of molecular hydrogen to be absorbed (or desorbed) by spiroids in a comparison with carbon spheroids. The goal of the study is to demonstrate whether the maximum concentration of absorbed hydrogen might be obviously achieved for the case of carbon spiroidal particle in comparison with a spheroidal one, containing the same number of atoms. The stability and dynamics of the spiral carbon nanoonion- adsorbed hydrogen are studying in the temperature range 4.2 to 2000 K. The dynamics of the adsorption process is discussed with relation to temperature limitations for hydrogen storage and biological applications.

Resume : Modification of the fullerene cage with the residues of thiols, phosphites, amines and alcohols is an important approach towards preparing fullerene derivatives possessing valuable properties. In particular, our group developed reactions of C60Cl6 with C[1], P[2], N[3] and S[4]-nucleophiles for synthesis of water-soluble fullerene derivatives for biomedical applications, e.g. compounds with potential antiviral and antibacterial activities. Here we report DMSO-promoted reactions of chlorofullerene C60Cl6 with alcohols and water producing smoothly С60(OR)5Cl derivatives in high yields. Particular interesting was the fact that addition of DMSO suppressed dramatically the formation of elimination products such as C60(OR)2 and C60. This effect was ascribed to the stabilization of intermediate anion-radicals via solvation with the DMSO molecules. Synthesis and complete characterization of five novel С60(OR)5Cl derivatives will be presented including the corresponding fullerenol (R=H). The first water-soluble compound C60(OCH2CH2COOH)5Cl with the solubilizing groups attached to the carbon cage via C-O linkages has been synthetized in two steps. Some physicochemical and biological properties of this compound will be discussed. [1] O. A. Troshina et al, Org. Biomol. Chem., 2007, 5, 2783 [2] A. A. Yurkova et al ,Chem. Commun., 2012, 71, 8916 [3] A. B. Kornev et al, Chem. Commun., 2012, 48, 5461 [4] E. A. Khakina et al, Chem. Commun., 2012, 48, 7158

Resume : The results obtained through the optimization of molecules gave us the different distances and angles according to the methods and bases applied with a C2v symmetry. We were able to determine the total energies, the energy gap ΔE (HOMO-LUMO) of the four conformers trans-transoid; trans-cisoid; cis-transoid; cis-cisoid. (the semi empirical AM1+PM6 at 6-31G and 3-21G** levels) and finally a comprehensive analysis on the topological charges. The analysis of the results show that for the eight molecules, the trans-transoid conformer is energetically very stable compared to the cis-cisoid one, this stability is confirmed by the obtained values for the total energy. The increase in the stability energy leads to a less important Homo-Lumo energy gap. The analysis of the optimized geometrical parameters of the ten molecules using the AM1 and PM6 methods, are in agreement with the experimental structures characterized by X-ray diffraction. Finally, we were able to determine the reaction profiles of the Cis-Trans isomerization reactions of the decapenta-ene in the gas phase, and to calculate the activation energy (Ea), as well as the diagrams of energies E (eV) based on the coordinates of the isomerization reaction of its molecules, and molar absorption according to energy calculated by the method HF at 6-31G and 3-21G** levels. Thus we have to determine the Spectrum IR of all the molecules by (AM1) and PM6. Keywords: substituted decapenta-ene , semi empirical, HF (AM1+PM6),

Resume : In order to understand better electron transfer mechanism of enzymes or proteins and eventually to develop sensitive enzyme or protein based biosensors, in this presentation we will discuss the application of graphene as the electrode material for the electron transfer of Horseradish Peroxidase (HRP). Chitosan was applied as a binder. Such an interface was characterized using voltammetry and impedance techniques. The electron transfer process of HRP as well as the electrocatalytic reduction of H2O2 were studied. Immobilized HRP shows a reduction peak at -0.33 V vs. SCE, which retains high ac-tivity towards the electrocatalytic reduction of H2O2. The H2O2 sensing is workable in the range from 28 µM to 2.0 µM. The Michaeclics-Menten model was applied to in-vestigate HRP kinetics at such an interface. The Michaelis constant was calculated to be 0.29 mM. Such an interface is promising to be used as a H2O2 biosensor for different applications.

Resume : A universal interface was constructed for electrocatalytic oxidation of fuel liquids, including alcohols, carboxylic acids and aldehydes. Such an interface was fabricated using carbon nanotubes as the catalyst support and palladium nanoparticles as the electrocatalysts. It was characterized using transmission electron microscope, energy dispersive X-ray spectroscopy, x-ray diffraction, voltammetry, and impedance. On such an interface, the oxidations of those liquid fuels occur similarly in two steps: the oxidations of freshly chemisorbed species in the forward (positive-potential) scan, and then in the reverse scan (negative-potential) the oxidations of the incompletely oxidized carbonaceous species formed during the forward scan. The oxidation charges were adopted for the first time to study their reaction mechanisms and oxidation efficiencies. The oxidation efficiency follows the order of aldehyde (formaldehyde) > carboxylic acid (formic acid) > alcohols (ethanol > methanol > glycol > propanol). Such an interface is thus promising to be applied as the anode for the facilitation of direct fuel cells.

Resume : The chemical modification of diamond powder surfaces has been investigated actively in order to enable their application in material science for transforming the surface properties from the original ones. Optically active organic compounds have attracted much attention in the field of medicinal chemistry. In order to separate racemic molecules, chiral stationary phases, which consist of silica or polymers as fillers containing chiral parts, are normally used in the chromatographic method. Diamond powder is a candidate for replacing such materials, since it is chemically stable against any solvent. In this paper, we report on the photochemical modification of diamond powder with optically active functionality and on an investigation of the chiral recognition ability for separating racemic compounds. The photochemical modification of H-terminated diamond powder (particle size 500 nm) was carried out by the irradiation of a low-pressure mercury lamp in the presence of the alkene-containing optically active amide in CH3CN at room temperature with stirring in an argon atmosphere. After the removal of CH3CN solution from the reaction mixture, the residual powder was analyzed by DRIFT, XPS, Raman and mass spectroscopy. These results suggest the covalent attachment of the linker molecule containing the optically active amide group occurred on the surface of diamond powder. The application of the powder to the optical resolution of racemic compounds will be also discussed.

Resume : Recently, fluorescent carbon dots have emerged as eligible candidates to take the place of semiconductor QDs due to their numerous advantages, including high photostability, emission tunability, water solubility and potential for use as optical imaging tools. Many research groups have synthesized CNDs via different techniques and explored their exciting properties, such as their different emission colours, powerful energy transfer components in photocatalysis, and so on. However, fluorescent CNDs are restricted to the solution phase (mainly in aqueous medium) and need attention on their availability in the form of thin films. Herein, we report a novel method for in-situ fabrication of large-area carbon quantum dots flexible film. First, 20 mL Peroxo-Titanium Complex (PTC) and 30 mL 30% H2O2 together with 20mL absolute alcohol were mixed in 100 mL Teflon-lined stainless steel autoclave, which was then sealed and maintained at 180 °C for 3 days. After the reaction, the CNDs aqueous solution was obtained. Then, a 10cm X10 cm flexible polymer substrate (PET film) was dipped into aniline solution for 24 h, and aniline acting as a monomer can be first absorbed onto the surface of the PETfilm due to their similar molecular polarity. The as-pretreated PET substrates were then immersed into a mixed solution (30 mL as-prepared CNDs aqueous solution and 30 mL PTC solution) at 80 ℃ 1 h, and 10cmX10cm large-area carbon quantum dots flexible film was obtained. This novel approach for large-area carbon quantum dots flexible film may expand the scope of application of carbon quantum dots.

Resume : Nowadays the interface between cells and man-made substrates becomes more and more important. A lot of novel materials are produced that should be suitable for implantation or for drug release into the body. One important section of these materials is carbon materials. They provide biocompability, since they consist of the same materials as cells, as well as tunable electrical and physical properties. Thus we focus this work on carbon materials. All implant materials must meet special criteria before being put into the body, however especially implantations inside the brain are critical. In this case there is often the additional requirement for exceptional electrical performance of the material. Therefore carefully testing of the biocompability of novel materials is of special interest. To minimize the risks, these materials are tested beforehand in vitro. Here, interactions of neurons with substrates indicate how brain tissue can interact with an implant at the microscopic level. On the other side, implantations into the heart are quite common and materials are tested for their chemical and mechanical stability. Again, a cell-model is of help; cardiomyocytes are used to mimic heart-muscle-cells. Additionally both cell types are electrically active, which makes it possible to test electrical devices made from the carbon materials with them. One important carbon material is graphene. It is known for its stability, flexibility and also its conductivity. Additionally, growth of electrically active cells on graphene was shown previously. This makes it a good candidate for, on the one side biocompatible applications, and on the other side for electronical devices. For example, graphene is used in field-effect-transistors. This provides a useful device to measure cell activity. For this purpose cells were seeded on substrates and fixed. Afterwards the samples were observed and cut using a focused ion beam. With cross sections of a sample it is possible to investigate the cell-substrate interface. In addition the rigidity of a cell on a substrate can be estimated. The rigidity displaces how much a single cell bends between two structures. Furthermore, not only planar graphene in field-effect-transistors but also structured graphene is investigated. Especially the interaction of cells with three dimensional structures is of interest. These structures enhance the surface area and thus improve the conduction from electrical signals towards the cells. A novel three dimensional material is investigated: carbon nanotubes (CNTs) which are covered with diamond [1]. The CNTs were covered with conductive boron-doped diamond. Also on this substrates the biocompability and the interface of cells to the substrate is of interest. Especially on these three dimensional structures the focus is laid on the contact points a cell build to attach to the substrate. In general it is interesting to know, how the cell reacts and adheres to the surface of the substrates. On the other side it is also of interest if thin substrates (like graphene layers) get influenced by the cells. Another question we would like to address is what are the limiting factors for a neuronal cell to adhere to a substrate. 1. Hébert, C. Mazellier, J.P. Scorsone, E. Mermoux, M. Bergonzo, P. Boosting the electrochemical properties of diamond electrodes using carbon nanotube scaffolds. Carbon 71(0), 27-33 (2014).

Resume : Recent researches have revealed that beta-amyloids can interact with fullerene, graphene and carbon nanotubes opening the way for the potential use of carbon allotropes based field-effect transistors for beta-amyloids sensing. The investigation of the interactions with the amyloids associated with human neurodegenerative diseases, beta-amyloids (1-40) and (1-42), is important for understanding the toxicity of the carbon based nanomaterials which are promising for biomedical applications. This paper presents a study about the deposition from solution of beta-amyloids (1-40) and (1-42) films on substrates of Si and Si covered by fullerene using Langmuir-Blodgett method, with the purpose to emphasize the effect of this carbon allotrope on the aggregation and fibrillar nanostructures formation processes and as consequence, on the toxicity of amyloids. The effect of fullerene on the physical properties of the amyloid film has also been investigated. SEM and AFM measurements gave details about the morphology, PL spectroscopy about the intrinsic fluorescence and UV-Vis spectroscopy about the degree of disorder in the films in correlation with the deposition conditions related to surface pressure, dipping speed, compression speed, number of cycles. The effect of cholesterol on the aggregation process and fibril-like formation was also studied in the absence and presence of fullerene layer. The charge carriers transport in amyloids film was investigated by drawing the I-V characteristics. The effect of the fullerene layer on the electrical response is analyzed in correlation with the degree of disorder.

Resume : Diabetes has been assigned next to cancer, cardiovascular and chronic respiratory diseases as the most leading cause of death and disability. A close monitoring of blood glucose concentrations plays a significant role in the diagnostics and prevention of diabetes and tremendous efforts have been put into the development of blood glucose sensors. In this presentation, a special focus will be given on the use of reduced graphene oxide (rGO) nanohybrids for the sensitive sensing of glucose in an enzyme free manner. Boronic acid modified rGO as well as electrophoretically formed rGO/Ni(OH)2 were used for this purpose and their fabrication and sensing characteristics will be discussed. Moreover, reduced graphene oxide matrixes how shown additionally compliant with efficient insulin loading and release. In type 1 diabetes, absolute deficiency of insulin production results from massive auto-immune destruction of pancreatic beta cells. For this reason, the main therapy consists in delivering exogenous insulin. The treatment methods require numerous daily injections of insulin administered by subcutaneous needle injection, insulin pen and catheters connected to insulin pumps. In this presentation, the advantage of flexible electrodes modified with reduced graphene and loaded with insulin, to electrically trigger insulin release over time will be presented. A special focus will be on the development of insulin-impregnated conductive matrixes and the influence of potential and current on the biological activity of released insulin. References: Q. Wang, I. Kaminska, J. Niedziolka-Jonsson, M; Opallo, M. Li, R. Boukherroub, S. Szunerits, Biosensors and Bioelectronics, 2013, 50, 331-337 P. Subramanian, J. Niedziolka-Jonsson, A. Lesniewski, Q. Wang, M. Li, R. Boukheroub, S. Szunerits, J. Mater. Chem A, 2014, 2, 5525-5533 K. Turcheniuk, M. Khanal, A. Montorina, P. Subramanian, A. Barras, V. Zaitsev, V. Kuncer, A. Leca, A. Martoriati, K. Cailliau, J.-F. Bodart, R. Boukherroub, S. Szunerits, RSC Adv. 2014, 4 (2) 865-875. F. Teodorescu, L. Rolland, V. Ramarao, A. Abderrahmani, D. Mandler, R. Boukherroub, S. Szunerits, Chem. Commun, 2015, 51, 14167

Resume : The main objective of the work is the development of novel methods for the synthesis and functionalization of conductive nanocarbons for a new generation of field effect transistor sensors suitable for high sensitivity bio-sensing applications. The primary interest of this presentation is focused on the growth, patterning and functionalization of vertically aligned carbon nanotube deposits from Ni catalyst, where all steps are performed by low temperature RF plasma processes. This type of catalyst deposition, material synthesis and functionalization is rather rapid, low cost and environmentally friendly (no solvents or toxic products by functionalization or deposition processes) leading also to reduction of the temperature needed for the CNT growth from metallic catalysts. The obtained systems are highly organized, well aligned and mechanically and chemically stable on different Si-based supports used in microelectronics as it can be observed. Depending on experimental conditions the CNT carpets are very dense and homogeneous on the entire substrate surface. The growth kinetics were observed by in-situ Raman spectroscopy, further analysis of as synthesized and functionalized CNTs were obtained by TEM, SEM, XPS, NEXAFS. Carbon nanotubes were successfully functionalized (in nitrogen plasma) with amino, hydroxyl and carboxyl groups. Furthermore the first tests of protein adhesion to the functionalized surfaces were performed by means of Bio-Rad DC Protein Assay, photoluminescence and FTIR spectroscopy, as well as scanning electron and optical microscopy of selected samples. These first results were positive showing the way for further steps in the development of targeted FET sensor devices.

Resume : Graphene has attracted strong scientific and technological interest in recent years. It has shown great promise in many applications, such as electronics, energy storage and conversion (supercapacitors, batteries, fuel cells, solar cells), and bioscience/biotechnologies because of its unique physicochemical and electronic properties such as high surface area (theoretically 2630 m2/g for single-layer graphene), excellent thermal conductivity and electric conductivity, and strong mechanical strength. Graphene also has numerous potential applications in biotechnology, including biosensing, disease diagnostics, antibacterial and antiviral materials, cancer targeting and photo thermal therapy, drug delivery, electrical stimulation of cells, and tissue engineering. Interactions of amino acids, DNA/RNA bases, and small molecules with graphene and carbon nanotubes are well studied using experimental and theoretical techniques. These studies indicate that noncovalent interactions such as π−π stacking and X−π (X = CH, OH, NH, etc.) stabilize the nucleobase and amino acid complexes of grapheme. Despite the importance of biomolecules–graphene interactions, a detailed understanding of the adsorption mechanism and features of biomolecules onto the surfaces of graphene is lacking. It is required the immobilization of biomolecules on the surface of graphene for design and production of bioelectronics devices. The interactions of biomolecules and graphene are long-ranged and very weak. Development of new techniques is very desirable for design of bioelectronics sensors and devices. Better understanding of interaction between amino acids with these 2D surfaces will provide better understanding of same interaction mechanisms for peptides and proteins. Because of its crucial biological roles such as cell and tissue remodeling, it makes possible to gain new know how. At the same time, the track and detection of amino acids will provide detection of several diseases by using biosensors. As an example, it is possible to diagnosis of malaria disease by detecting histedine and diagnosis of several cancer types and Parkinson’s disease by detecting leucine. In this work, we have performed density functional theory (DFT) with vdW-DF method calculations for exploring the adsorption geometries, adsorption energies, electronic band structures and adsorption dynamics of Histidine and Leucine (model amino acid)/graphene composite system. It is also shown that how modify structural and electronic properties of amino acids on graphene by applied charging and perpendicular electric field.

Resume : Direct electron transfer (DET) is a ubiquitous phenomenon in chemical, electrical, and biological systems. However, to achieve efficient DET in biological systems, realizing intimate electrical contacts with redox biomolecules at nanoscale is crucial. Here we report an approach that enables highly facilitated biomolecular electron transfer with unprecedented versatility and applicability by rationally interfacing enzymes with hydro-dynamically assembled conductive nanomesh of single-walled carbon nanotubes (SWNTs). Intact SWNTs were hydro-dynamically assembled into a conductive nanomesh with extremely well controlled nanostructures over large area, and high electrical and electrochemical conductivity. The conductive nanomesh was then layered onto metallic substrates to serve as a nanostructured electrical platform for biomolecular electron transfer. Enzymes were rationally interfaced with the nanomesh after controlling the interface charges, enabling both intimate nanoscale electrical contacts to biomolecules for facilitated electron transfer and highly porous nanostructures for high sensitivity. Using this layered conductive nanomesh-enzyme platform that preserved nanoscale feature of the electrical wires, SWNTs, and enabled stable and intimate electrical contract between nanomesh and enzymes, we successfully demonstrated DET for eight different enzymes with various types of catalytic activities. We further showed DET even on a flexible integrated device platform and demonstrate a flexible DET-based glucose-biosensor, for the first time, to the best of our knowledge. The electron transfer efficiency of these flexible integrated biosensors was comparable to that obtained using commercialized screen printed electrodes. The results promote a promising approach to directly and efficiently control electronic states of enzymes using a hierarchically assembled platform of nanoscale electronic materials and biological molecules for wearable biosensors, health-monitoring systems, and human-machine interfaces. We envision that since our concept is generic, it could be also extended to other research areas in which biomolecular electron transfer is important such as artificial photosynthesis, biofuel cells, and bio-mechanistic studies.

Resume : Copper nanoparticles (NPs) decorated with Carbon quantum dots (CQD’s) was prepared by a facile thermal treatment, and further employed as a novel sensing material for fabricating the sensitive non-enzymatic glucose sensor. Compared with pure Copper NPs, showed enhanced electrocatalytic activity to glucose oxidation due to the integration of CQD’s. The presented sensor showed excellent performances for glucose detection including wide linear range of 0.2–5.6 mM, low detection limit (6,93 μM, ), high sensitivity (0,811 μA mM−1 cm−2), good selectivity. Such properties would promote the potential application of the CQD’s as enhanced materials in fabricating sensors for chemical and biochemical analysis.

Resume : Two major promising applications of nanotechnology towards the treatment of cancer are the control over molecular binding sites and the detection of binding phenomena, which could lead to better therapies, earlier cancer detection, and better tools for cancer research. For these pursuits, new methods are needed to quantify disease biomarkers and other bioanalytes. The real-time and spatially-resolved detection and identification of analytes in biological media present important goals for next-generation nanoscale sensors. To this end, we employ the intrinsic near-infrared fluorescence of single-walled carbon nanotubes. The emission of semiconducting nanotubes is photostable yet sensitive to the immediate environment. Analyte identification is achieved by modulation of the nanotube’s spectral response, resulting in distinct optical fingerprints. The responses can be spatially mapped in live cells and tissues, and measured in real-time with sensitivity down to the single-molecule level, facilitating unprecedented bioanalytical studies.

Resume : Carbon-based materials represent a wide family of materials which continuously gain in interest in the field of nanoscience and nanotechnology. This growing interest is explained by the manifold allotropic forms (carbon nanotubes, graphene, nanodiamond, etc.) and the covered applications going from novel properties to functional applications (sensors, energy, adsorption etc.). In this context, carbon-based nanomaterials are important issue when innovative and materials are seeked. As member of carbonaceous materials, carbon nanotubes (CNTs) offer properties [1] closely related to their structure and their surface chemistry. With chemical or physical surface modification, these materials offer several possibilities to target specific applications. Such a surface modification is a key issue to highlight the impact of surface chemistry, to design original sensitive nanomaterial and simultaneously overcome the lack of solubility. The modification/functionalization issue is used here to make carbon nanotubes more processable and more sensitive to gases. In this presentation, the role of surface modification to access to solution processing and to achieve sensitive sensors will be discussed and argued. Additionally, the modified carbon-based materials will be characterized by techniques such as UV-Vis spectroscopy, TGA, TEM, Raman analysis, electrical characterization etc. References: [1] A. Krueger, Carbon Materials and Nanotechnology, Wiley-VCH Verlag, 2010, 123.

Resume : Sensing devices which can detect human activities and psychological conditions are of great importance for human monitoring, health monitoring, human-machine interfaces, and robotics. In particular, a multitude of sensors for human-machine interfaces which collect various conditions of human and surrounding environment send to smart electronic systems are highly demanding for high interactivity between human and smart systems. As an approach for this purpose, patchable sensors on human body have been investigated. In this work, the stretchable and transparent strain sensor based on newly designed, highly sensitive piezoresistive materials was used to detect small strains induced on human skin. Stacked structure of piezoresisitive nanocomposite of single-walled carbon nanotube (SWCNT) with conductive elastomer of polyurethane(PU)-poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) showed high strain sensitivity with the gauge factor up to 63 under the small strain, elongation up to 100%, and optical transparency of 62%. The device showed a good stability after cyclic stretching and releasing. The sensor patched on human face was demonstrated to detect to small strains on the skin of a human face induced by minute movements of muscles related to facial expressions caused by emotions and eyeball movements.

Resume : Carbon materials and nanomaterials are of great interest for biological applications. To realize their potential it is however critical to control formation and composition of the biomolecule corona that forms over short time scales once carbon contacts physiological media. It is therefore critical (a) to understand how physical/chemical properties of carbon surfaces affect their interactions with biomolecules, and (b) to develop new methods for controlling carbon bioresponses. In this presentation we will discuss biomolecule adsorption studies at model carbon surfaces. Using a combination of surface spectroscopies, nanogravimetry, electrokinetic studies and scanning microscopy, we investigated biomolecule adsorption at carbons before and after surface modifications that result in changes to surface wetting, charge density and/or steric repulsion. In particular, we will discuss the effects of glycan immobilization via aryldiazonium chemistry on protein adsorption, and how glycan structure affects carbon bioresponse. Protein fouling at glycan-modified carbon was found to decrease by 30-90%; this appears to result from changes in wetting properties and an increase in surface basicity with respect to unmodified carbons. Interestingly, aryldiazonium chemistry was found to be an excellent route for tailoring surface chemistry while leaving surface charge density unaltered, which is important for controlling solid-biomolecule interactions. Finally, we report on the effects of dry modification methods on interactions of carbons with proteins and lipids, aimed at understanding how surface properties affect the interplay between these two important families of biomolecules.

Resume : Nanomaterial-based approaches have recently emerged as an attractive strategy in combating hematology-related disorders, such as surface-activated thrombosis and malaria. Of all classes of nanomaterials, the graphene-based materials, specifically graphene oxide (GO), have been actively pursued for this purpose due to their superior physico-chemical properties and biocompatibility. Here, we investigate the molecular interactions between GO and blood plasma proteins to gain an insight into the bio-physico-chemical activity of GO for hematological applications. We elucidate the various aspects of the GO-protein interactions, particularly, the adsorption, binding kinetics and equilibrium, and conformational stability of proteins. We observe that GO possesses a high loading capacity for all plasma proteins and these proteins bind strongly to GO. We also note that these interactions are significantly dependent on the lateral size and concentration of GO. Based on the exceptional protein adsorption on GO and the size- and concentration-dependent molecular interactions, we evaluate the antithrombotic and antimalarial properties of GO and subsequently, demonstrate its potential in mitigating these hematological disorders. We anticipate that this work will provide a general perspective on the GO-plasma protein interactions and shall facilitate the further exploration of the nanotechnology-based strategies for hematological and other biological applications. References [1] Kenry, K.P. Loh, C.T. Lim, Small 11:5105-5117 (2015).

Resume : Reduction chemistry can been used to both disperse and functionalise carbon nanomaterials in a mild and effective manner. Here, a simplified and accelerated route to reduced carbon nanomaterial solutions has been identified [1] and the conditions required to maximise surface functionalisation have been elucidated. In particular, an idealised intermediate reducing metal concentration is required to maximise available charge for functionalisation while limiting counterion condensation.[2] The extent of functionalisation was compared between carbon nanomaterials of differing dimensionalities (single and multi-walled carbon nanotubes, few layered graphite, graphite nanoplatelets, and carbon black). Through functionalisation with monoterminated polymers, the surface-modified carbon nanomaterials can act as effective nucleants for 3D protein crystals, with the impact of nanomaterial dimensionality systematically compared. These studies not only further our understanding of carbon nanomaterial modification and use, but demonstrate the validity and effectiveness of studying carbon nanomaterials as a family of related structures. This approach will hopefully inspire future studies to follow suit to help select the best material for specific applications. (1) Clancy, A. J.; Melbourne, J.; Shaffer, M. S. P. J. Mater. Chem. A 2015, 3, 16708. (2) Morishita, T.; Clancy, A. J.; Shaffer, M. S. P. J. Mat. Chem. A 2014.

Resume : In the past decade, carbon-based three-dimensional (3D) architectures have received increasing attention in science and technology due to their fascinating properties, such as huge surface area, macroscopic bulky shape and interconnected porous structures, enabling them to be one kind of most promising materials for water remediation. In this talk, I will summarize the recent development in design, preparation and applications of carbon-based 3D architectures and introduce our recent research progress on the preparation of carbon aerogels (CA) for water treatment. Three kinds of CA, which are made from graphene, raw cotton and waste paper, respectively, have been successfully used as novel, efficient and recyclable sorbents for oils and organic solvents. The CA can absorb a variety of oils and organic solvents with outstanding recyclability. The maximum sorption capacity is as high as 192 times the weight of CA. Compared with the sorption efficiency of commercialized products (e.g. activated carbon), the sorption efficiency of CA is extremely high. Moreover, it still possesses a high sorption capacity after five cycles by using distillation, burning or squeezing methods to recover the absorbed liquids. References [1] B. Chen, Q. Ma, C. Tan, T.-T. Lim, L. Huang, H. Zhang*, Small, 2015, 11, 3319. [2] H. C. Bi, X. Huang, X. Wu, X. H. Cao, C. L. Tan, Z. Y. Yin, X. H. Lu, L. T. Sun,* H. Zhang*, Small, 2014, 10, 3544. [3] H. C. Bi, Z. Y. Yin, X. H. Cao, X. Xie, C. L. Tan, X. Huang, B. Chen, F. T. Chen, Q. L. Yang, X. Y. Bu, X. H. Lu, L. T. Sun*, H. Zhang*, Adv. Mater., 2013, 25, 5916.

Resume : Pure and doped carbon nano-structured materials (single-walled carbon nanotubes (SWCNT), graphene sheets, etc.) are actively studied at present as perspective materials for various macro-scaled practical applications. The properties of such carbon materials can be varied in wide range when they are functionalized by additional non-carbon components. Efficient functionalization is possible when carbon materials form chemical bonds with functionalizing compounds [1]. Theoretical modeling of molecular adsorption on the surface of CNTs and graphene sheets can shed light on this issue. In this work we consider adsorption of XO42- (X = Cr, Mo, W) molecular oxyanions on the surfaces of pristine and N(B)-doped SWCNTs and graphene. DFT-based geometry-optimized calculations of the electronic structures of the SWCNTs and graphene molecular clusters with adsorbed oxyanions are carried out by Gaussian 03 program package [2]. Relaxed geometries, binding energies between oxyanions and adsorbents, energy barriers for desorption, electronic wavefunction contours were calculated and analyzed. Perspectives for efficient functionalization of carbon nano-structured materials by oxide compounds are discussed. [1] Yu. Hizhnyi, S.G. Nedilko, V. Borysiuk, and V. A. Gubanov // Int. J. of Quant. Chem. (2015) doi: 10.1002/qua.24953. [2] M.J. Frisch, G.W. Trucks, H.B. Schlegel, et al. // Gaussian 03 (Gaussian, Inc., Wallingford, CT, 2003).

Resume : Among all the physical and chemical properties of nanocarbons, a special interest is focused on their high gas adsorption capacity. If their porous nature and high specific surface area provide high gas adsorption rates, these are strongly modulated by the surface chemistry of nanomaterials. These features lead to different applications including energy storage, purification, pre-concentration or sensing. This lecture deals with the impacts of porosity and surface chemistry of nanocarbons on gas adsorption toward oxidizing pollutants and aromatic hydrocarbons. Firstly, adsorption of nitrogen dioxide and ozone on different nanocarbons (single and multi-wall nanotubes, nanowires, nanodiscs, activated carbons) has been studied. By means of thermal and chemical treatments on pristine nanocarbons consecutively characterized by EPR, Raman spectroscopy and NEXAFS, the role of dangling bonds and surface oxygenated groups on gas adsorption are manifest. The influence of SSA has been also established. Secondly, adsorption of aromatic hydrocarbons on mesoporous and microporous carbons has been investigated. Based on VOC adsorption/desorption isotherms, physisorbed VOC quantity seems correlated to the textural properties of carbon, while the strongly bonded VOC related to the surface chemistry as highlighted by Temperature Programmed Desorption coupled with Mass Spectrometry (TPD-MS) analyses. At last, performances of sensor-systems involving such nanocarbons will be discussed.

Resume : Carboxylic acid groups play a key role in chemistry ranging from biologically relevant molecules to materials chemistry, as they can be further modified to achieve different functionalisations. The presence of COOH groups in different forms of graphene improves solubility in water, facilitating the chemical processing and functionalisation of these new materials. Understanding the acid/base properties of COOH groups will help optimise processes and enable new graphene-based applications. Graphene nanoflakes (GNF) used in this study are single sheets, have lateral dimensions of ca. 30 nm and are edge-terminated with COOH groups. The small size of the flakes and the high concentration of the acidic edge groups lead to different bonding environments, such as armchair and zigzag edge, as well as varying degrees of electrostatic and hydrogen-bonding interactions between groups. Consequently, deprotonation of GNF has been observed to occur over a wide pH range. The effect of electrode potential on the acid/base properties of GNF was studied using spectroelectrochemistry. A BDD working electrode, modified with GNF complexed with Ca2+ and Ba2+, was polarised and ATR-FTIR was used to monitor changes to GNF and solution species. The influence of solution pH, electrolyte concentration and identity of ions was explored. Decomplexation of Ca2+ and Ba2+ from carboxylates enabled potential-induced protonation/deprotonation of COOH groups and shifts in the C=O frequency to be observed.

Resume : Carbon dioxide is the ultimate by-product of all processes involving oxidation of carbon compounds. Due to its green-house effect, researches on its chemical conversion have been paid extensive attention in past decades. Carbon electrodes have the advantages of being chemically inert at negative potential ranges in all media and high offset potentials for hydrogen evolution in comparison to metal electrodes, and therefore are the most suitable electrodes for electrochemistry and electrochemical conversion of CO2 into valuable chemicals. In this presentation, we will summarize on carbon electrodes the voltammetry, electrochemical and electrocatalytic CO2 reduction, as well as electron synthesis using CO2 and carbon electrodes. The electrocatalytic CO2 reduction using carbocatalyts and the application of boron-doped diamond for CO2 conversion will be highlighted.

Resume : Nanostructured ZnO/diamond has high surface area, good biocompatibility, chemical stability and non toxic properties making it interesting notably for electrochemical biosensors applications [1]. The electrodeposition (ED) of ZnO on boron-doped diamond (BDD) represents an interesting way for the preparation of such heterostructures which are usually obtained by high temperature process [2-3]. We recently performed for the first time the ED of ZnO on BDD using the method based on the reduction of dissolved O2 leading to various ZnO structures [4]. In this work, we focus on the influence of the BDD surface chemistry either H- or O-terminated obtained by different oxidation treatments (electroless[5] or anodic [6]) on the ZnO deposition process. Surface terminations are followed by contact angle and XPS analyses. The morphologies and structures of ZnO deposits are characterized by XRD and SEM. Besides playing on deposit morphology, this work shows that the surface terminations of BDD (-CH, -COH, -COOH, -COC- or -C=O) have also a strong effect on the ZnO deposit adhesion. [1] Sensors. 2010, 10, 1216–1231. [2] Appl. Surf. Sci. 2011, 258, 333–336. [3] Diam. Relat. Mater. 2011, 20, 351–354. [4] Diam. Relat. Mater. 2016, 62, 1-6. [5] Diam. Relat. Mater. 2011, 20, 944-950. [6] Diam. Relat. Mater. 2007, 16, 316-325