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Denis Spitzer - One of the best experts on this subject based on the ideXlab platform.
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Nanodiamond coating by polyethylenimine for optical limitation
Diamond and Related Materials, 2019Co-Authors: Vincent Pichot, M. Guerchoux, Olivier Muller, Mazheva Guillevic, Philippe Fioux, L. Merlat, Denis SpitzerAbstract:Abstract Polyethylenimine (PEI) is used to elaborate detonation Nanodiamonds coated with a polymer material. Evolution of the Nanodiamonds surface charge depending on the PEI concentration is revealed by a zeta potential study. While the surface charge of the nanodiamond is negative due to its oxygenated functional groups, the cationic polymer allows reversing it to a positive one. Spectroscopy characterizations are used to investigate the PEI interaction with the Nanodiamonds and to estimate the very small thickness of the PEI layer on the Nanodiamonds surface. The oxygenated functional groups of the nanoparticles interact electrostatically with the PEI amine groups. The good performances of the non-linear optical properties of this material are demonstrated at a wavelength of 1064 nm.
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Optical properties of functionalized Nanodiamonds.
Scientific reports, 2017Co-Authors: Vincent Pichot, L. Merlat, O. Muller, Aymeric Sève, A. Yvon, Denis SpitzerAbstract:Detonation Nanodiamonds exhibit strong nonlinear optical properties depending on their electronic properties. In the present paper, the nanodiamond functional groups are chemically modified to obtain Nanodiamonds with primary amines on their surface. The optical properties of such Nanodiamonds placed in water suspensions are studied and compared with the one of classical detonation Nanodiamonds. Transmission, scattering and Z-scan experiments are performed for two different wavelengths (532 nm and 1064 nm). A lower threshold for optical limiting associated to more pronounce non-linear optical effects is detected at the wavelength of 1064 nm compared to the one at 532 nm. This effect may be due to a stronger nonlinear backscattering behavior at 1064 nm. Moreover, a striking result obtained from the Z-scan experiments reveals a completely different behavior of the functionalized Nanodiamonds for both wavelengths. This result is discussed in regard to the electronic properties of the material and possible charge transfer.
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Nanodiamond for tuning the properties of energetic composites
Journal of hazardous materials, 2015Co-Authors: Vincent Pichot, Marc Comet, Julien Miesch, Denis SpitzerAbstract:Bismuth oxide (Bi2O3) particles were coated by detonation Nanodiamonds. The resulting nanocomposite materials were mixed with an aluminum nanopowder (≈ 100 nm) to prepare nanothermites, with reduced sensitivity to friction and electrostatic discharge (ESD). The use of nanodiamond for this purpose is reported here for the first time. Their numerous qualities such as their small size, antifriction properties and thermal conductivity make them ideal candidates. Small amounts of detonation Nanodiamonds allow obtaining impressive desensitization, making thus modified Bi2O3/Al nanothermite safe to handle. A composition containing around 1 wt.% of nanodiamond has a sensitivity threshold to friction superior to 100 N instead of 5 N for the thermite without nanodiamond. Furthermore, the sensitivity threshold to electrostatic discharge increases to 20 times when the nanodiamond content reaches 1.8 wt.%. The antifriction properties of nanodiamond limit the scratching of Bi2O3 surface by Al particles. The desensitization to ESD is observed for a sufficient coverage of the oxide particles (1.8 wt.% of ND), which restrains the effect of the melt dispersion mechanism of aluminum and prevents the mixing of the oxidizing and the reducing parts of the composites. A good reactivity of the thermite could be maintained for nanodiamond content up to 2.6 wt.%. The carburizing of aluminum coming on contact with nanodiamond during the thermite reaction could be evidenced by X-ray Diffraction and calorimetry measurements and also participates to the desensitization of the nanothermite. This kind of desensitization by using detonation nanodiamond can also be applied to other nanothermites having low sensitivity threshold to friction and ESD.
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Two-dimensional nanodiamond monolayers deposited by combined ultracentrifugation and electrophoresis techniques
Applied Physics Letters, 2012Co-Authors: Loïc Schmidlin, Vincent Pichot, Sébastien Josset, Rémy Pawlak, Thilo Glatzel, Shigeki Kawai, Ernst Meyer, Denis SpitzerAbstract:Dense detonation Nanodiamonds deposit has been obtained through a coupled process: Electrophoretic deposition was applied to an ultracentrifugated detonation Nanodiamonds suspension. The resulting coating exhibits nearly complete 5 nm thick monolayer coverage of the substrate. The described process is a soft and easily tunable approach, particularly suitable for the development of sensors or the growth of high performance nanodiamond films. The proximity of the adsorbed nanoparticles on the substrate was demonstrated by scanning probe techniques, such as atomic force microscopy and scanning tunneling microscopy.
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Detonation Nanodiamonds for doping Kevlar.
Journal of Nanoscience and Nanotechnology, 2010Co-Authors: Marc Comet, Vincent Pichot, Benny Siegert, Fabienne Britz, Denis SpitzerAbstract:: This paper reports on the first attempt to enclose diamond nanoparticles--produced by detonation--into a Kevlar matrix. A nanocomposite material (40 wt% diamond) was prepared by precipitation from an acidic solution of Kevlar containing dispersed Nanodiamonds. In this material, the diamond nanoparticles (O = 4 nm) are entirely wrapped in a Kevlar layer about 1 nm thick. In order to understand the interactions between the nanodiamond surface and the polymer, the oxygenated surface functional groups of nanodiamond were identified and titrated by Boehm's method which revealed the exclusive presence of carboxyl groups (0.85 sites per nm2). The hydrogen interactions between these groups and the amide groups of Kevlar destroy the "rod-like" structure and the classical three-dimensional organization of this polymer. The distortion of Kevlar macromolecules allows the wrapping of Nanodiamonds and leads to submicrometric assemblies, giving a cauliflower structure reminding a fractal object. Due to this structure, the macroscopic hardness of Kevlar doped by Nanodiamonds (1.03 GPa) is smaller than the one of pure Kevlar (2.31 GPa). To our knowledge, this result is the first illustration of the change of the mechanical properties induced by doping the Kevlar with nanoparticles.
Vadym Mochalin - One of the best experts on this subject based on the ideXlab platform.
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effect of nanodiamond surface chemistry on adsorption and release of tiopronin
Diamond and Related Materials, 2019Co-Authors: Justin Beltz, Vadym Mochalin, Annalise R Pfaff, Ibrahim Munkaila Abdullahi, Alex Cristea, Nuran ErcalAbstract:Abstract Tiopronin is an FDA-approved thiol drug currently used to treat cystinuria and rheumatoid arthritis. However, due to its antioxidant properties, it may be beneficial in a variety of other conditions. One primary obstacle to its wider application is its limited bioavailability, which necessitates administration of high systemic doses to achieve localized therapeutic effects. Incorporation of a drug delivery vehicle can solve this dilemma by providing a means of controlled, targeted release. Functionalized nanodiamond is a promising theranostic platform that has demonstrated great potential for biomedical applications, including drug delivery. Design of nanodiamond theranostic platforms requires comprehensive understanding of drug-platform interactions, and the necessary physical chemical investigations have only been realized for a limited number of compounds. Towards the long-term goal of developing a nanodiamond-tiopronin treatment paradigm, this study aims to shed light on the effects of nanodiamond surface chemistry on adsorption and release of tiopronin. Specifically, adsorption isotherms were measured and fit to Langmuir and Freundlich models for carboxylated, hydroxylated, and aminated Nanodiamonds, and release was monitored in solutions at pH 4.0, 5.8, 7.3, and 8.1. Our results indicate that aminated Nanodiamonds exhibit the highest loading capacity while hydroxylated Nanodiamonds are the most effective for sustained release. Therefore, a high degree of flexibility may be afforded by the use of Nanodiamonds with different surface chemistries optimized for specific applications.
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Biomedical applications of nanodiamond (Review).
Nanotechnology, 2017Co-Authors: Kostiantyn Turcheniuk, Vadym MochalinAbstract:The interest to applications of nanodiamond in biology and medicine is on the rise over the recent years. This is due to the unique combination of properties that nanodiamond provides. Small size (~ 5 nm), low cost, scalable production, negligible toxicity, chemical inertness of diamond core and rich chemistry of nanodiamond surface, as well as bright and robust fluorescence resistant to photobleaching are the distinct parameters that render nanodiamond superior to any other nanomaterial when it comes to biomedical applications. The most exciting recent results have been related to the use of Nanodiamonds for drug delivery and diagnostics – two components of quickly growing area of biomedical research dubbed theranostics. However, nanodiamond offers much more in addition: it can be used to produce biodegradable bone surgery devices, tissue engineering scaffolds, kill drug resistant microbes, help us to fight viruses, and deliver genetic material into cell nucleus. All these exciting opportunities require an in-depth understanding of nanodiamond. This review covers the recent progress as well as general trends in biomedical applications of nanodiamond, and underlines the importance of purification, characterization, and rational modification of this nanomaterial when designing nanodiamond based theranostic platforms.
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adsorption of drugs on nanodiamond toward development of a drug delivery platform
Molecular Pharmaceutics, 2013Co-Authors: Vadym Mochalin, Ioannis Neitzel, Amanda Pentecost, Matthew Nelson, Chongyang Wei, Fang Guo, Yury GogotsiAbstract:Nanodiamond particles produced by detonation synthesis and having ∼5 nm diameter possess unique properties, including low cell toxicity, biocompatibility, stable structure, and highly tailorable surface chemistry, which render them an attractive material for developing drug delivery systems. Although the potential for Nanodiamonds in delivery and sustained release of anticancer drugs has been recently demonstrated, very little is known about the details of adsorption/desorption equilibria of these and other drugs on/from Nanodiamonds with different purity, surface chemistry, and agglomeration state. Since adsorption is the basic mechanism most commonly used for the loading of drugs onto nanodiamond, the fundamental studies into the details of adsorption and desorption on nanodiamond are critically important for the rational design of the nanodiamond drug delivery systems capable of targeted delivery and triggered release, while minimizing potential leaks of dangerous drugs. In this paper we report on a physical-chemical study of the adsorption of doxorubicin and polymyxin B on Nanodiamonds, analyzing the role of purification and surface chemistry of the adsorbent.
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adsorption of drugs on nanodiamond toward development of a drug delivery platform
Molecular Pharmaceutics, 2013Co-Authors: Vadym Mochalin, Ioannis Neitzel, Amanda Pentecost, Matthew Nelson, Chongyang Wei, Fang Guo, Yury GogotsiAbstract:Nanodiamond particles produced by detonation synthesis and having ∼5 nm diameter possess unique properties, including low cell toxicity, biocompatibility, stable structure, and highly tailorable surface chemistry, which render them an attractive material for developing drug delivery systems. Although the potential for Nanodiamonds in delivery and sustained release of anticancer drugs has been recently demonstrated, very little is known about the details of adsorption/desorption equilibria of these and other drugs on/from Nanodiamonds with different purity, surface chemistry, and agglomeration state. Since adsorption is the basic mechanism most commonly used for the loading of drugs onto nanodiamond, the fundamental studies into the details of adsorption and desorption on nanodiamond are critically important for the rational design of the nanodiamond drug delivery systems capable of targeted delivery and triggered release, while minimizing potential leaks of dangerous drugs. In this paper we report on a ph...
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maximizing young s modulus of aminated nanodiamond epoxy composites measured in compression
Polymer, 2012Co-Authors: Ioannis Neitzel, Vadym Mochalin, Junjie Niu, Jefferson Cuadra, Antonios Kontsos, Giuseppe R Palmese, Yury GogotsiAbstract:Abstract Nanodiamond, due to its superior hardness and Young's modulus in combination with its large surface area holds great potential for the mechanical reinforcement of polymer matrices. However, it is still not possible to take full advantage of these properties in polymer matrix composites. The main reasons are poor dispersion, agglomeration and a weak interface between nanodiamond and the polymer. Aminated nanodiamond can be used to form a strong covalent interface with an epoxy polymer. We show how Young's modulus can be further improved if an interference of Nanodiamonds amino groups with the epoxy stoichiometry is taken into account. Dispersion of nanodiamond is improved by slightly adjusting the manufacturing process, thus increasing Young's modulus of the composites. Predictions by a micromechanics homogenization method that consider nanodiamond agglomeration and dispersion suggest that Young's modulus can be further increased by slightly improving both parameters. For the first time we show that epoxy can be cured solely by Nanodiamonds amino groups without any additions of curing agent, resulting in a composite's Young's modulus measured by nanoindentation of up to ∼18 GPa – a 700% improvement over neat epoxy.
Yury Gogotsi - One of the best experts on this subject based on the ideXlab platform.
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adsorption of drugs on nanodiamond toward development of a drug delivery platform
Molecular Pharmaceutics, 2013Co-Authors: Vadym Mochalin, Ioannis Neitzel, Amanda Pentecost, Matthew Nelson, Chongyang Wei, Fang Guo, Yury GogotsiAbstract:Nanodiamond particles produced by detonation synthesis and having ∼5 nm diameter possess unique properties, including low cell toxicity, biocompatibility, stable structure, and highly tailorable surface chemistry, which render them an attractive material for developing drug delivery systems. Although the potential for Nanodiamonds in delivery and sustained release of anticancer drugs has been recently demonstrated, very little is known about the details of adsorption/desorption equilibria of these and other drugs on/from Nanodiamonds with different purity, surface chemistry, and agglomeration state. Since adsorption is the basic mechanism most commonly used for the loading of drugs onto nanodiamond, the fundamental studies into the details of adsorption and desorption on nanodiamond are critically important for the rational design of the nanodiamond drug delivery systems capable of targeted delivery and triggered release, while minimizing potential leaks of dangerous drugs. In this paper we report on a ph...
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adsorption of drugs on nanodiamond toward development of a drug delivery platform
Molecular Pharmaceutics, 2013Co-Authors: Vadym Mochalin, Ioannis Neitzel, Amanda Pentecost, Matthew Nelson, Chongyang Wei, Fang Guo, Yury GogotsiAbstract:Nanodiamond particles produced by detonation synthesis and having ∼5 nm diameter possess unique properties, including low cell toxicity, biocompatibility, stable structure, and highly tailorable surface chemistry, which render them an attractive material for developing drug delivery systems. Although the potential for Nanodiamonds in delivery and sustained release of anticancer drugs has been recently demonstrated, very little is known about the details of adsorption/desorption equilibria of these and other drugs on/from Nanodiamonds with different purity, surface chemistry, and agglomeration state. Since adsorption is the basic mechanism most commonly used for the loading of drugs onto nanodiamond, the fundamental studies into the details of adsorption and desorption on nanodiamond are critically important for the rational design of the nanodiamond drug delivery systems capable of targeted delivery and triggered release, while minimizing potential leaks of dangerous drugs. In this paper we report on a physical-chemical study of the adsorption of doxorubicin and polymyxin B on Nanodiamonds, analyzing the role of purification and surface chemistry of the adsorbent.
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maximizing young s modulus of aminated nanodiamond epoxy composites measured in compression
Polymer, 2012Co-Authors: Ioannis Neitzel, Vadym Mochalin, Junjie Niu, Jefferson Cuadra, Antonios Kontsos, Giuseppe R Palmese, Yury GogotsiAbstract:Abstract Nanodiamond, due to its superior hardness and Young's modulus in combination with its large surface area holds great potential for the mechanical reinforcement of polymer matrices. However, it is still not possible to take full advantage of these properties in polymer matrix composites. The main reasons are poor dispersion, agglomeration and a weak interface between nanodiamond and the polymer. Aminated nanodiamond can be used to form a strong covalent interface with an epoxy polymer. We show how Young's modulus can be further improved if an interference of Nanodiamonds amino groups with the epoxy stoichiometry is taken into account. Dispersion of nanodiamond is improved by slightly adjusting the manufacturing process, thus increasing Young's modulus of the composites. Predictions by a micromechanics homogenization method that consider nanodiamond agglomeration and dispersion suggest that Young's modulus can be further increased by slightly improving both parameters. For the first time we show that epoxy can be cured solely by Nanodiamonds amino groups without any additions of curing agent, resulting in a composite's Young's modulus measured by nanoindentation of up to ∼18 GPa – a 700% improvement over neat epoxy.
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Advances in Surface Chemistry of Nanodiamond and Nanodiamond–Polymer Composites
Ultananocrystalline Diamond, 2012Co-Authors: Ioannis Neitzel, Vadym Mochalin, Yury GogotsiAbstract:Nanodiamonds have excellent mechanical and optical properties, high surface areas and tunable surface structures. These properties make ND a highly promising material for nanocomposite applications, in particular, when used in polymer matrix composites. However, to take full advantage of Nanodiamonds in composite applications, their purity, rational control of surface chemistry, dispersion in the matrix, and interface between the nanofiller and the matrix need to be considered. This chapter summarizes recent developments in the optimization of nanodiamond surface chemistry and application of this material in polymer matrix composites.
Irina V. Perminova - One of the best experts on this subject based on the ideXlab platform.
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Tritium labelling to study humic substance-nanodiamond composites
Environmental research, 2020Co-Authors: Irina V. Abmetko, Maria G. Chernysheva, Natаlia A. Kulikova, Andrey I. Konstantinov, Andrey G. Popov, Gennadii A. Badun, Irina V. PerminovaAbstract:Abstract Nanodiamonds produced by the detonation method are used as lubricants, polishing compositions, polymer composites, etc. To reveal how Nanodiamonds differ in terms of surface properties and interact with natural organic matter, we used tritium-labelled humic substances to quantitively describe their adsorption onto the nanodiamond surface. It was shown that the adsorption of humic substances onto Nanodiamonds resulted in fractionation of humic substances that was strongly dependent on the zeta potential of Nanodiamonds in water but did not significantly affect the uptake of Nanodiamonds by wheat seedlings. The uptake of nanodiamond particles by plants was determined by the functional composition of the particle surface.
J R Rabeau - One of the best experts on this subject based on the ideXlab platform.
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processing 15 nm Nanodiamonds containing nitrogen vacancy centres for single molecule fret
Australian Journal of Chemistry, 2012Co-Authors: Jana M Say, Carlo Bradac, T Gaebel, J R Rabeau, Louise J BrownAbstract:Colour centres in Nanodiamonds have many properties such as chemical and physical stability, biocompatibility, straightforward surface functionalisation as well as bright and stable photoluminescence, which make them attractive for biological applications. Here we examine the use of fluorescent Nanodiamonds containing a single nitrogen-vacancy (NV) centre, as an alternative nano-label over conventional fluorophores. We describe a series of chemical treatments and air oxidation to reliably produce small (~15 nm) oxidised Nanodiamonds suitable for applications in bioscience. We use Forster resonance energy transfer to measure the coupling efficiency from a single NV centre in a selected nanodiamond to an IRDye 800CW dye molecule absorbed onto the surface. Our single-molecule Forster resonance energy transfer analysis, based on fluorescence lifetime measurements, locates the position of the photostable NV centre deep within the core of the nanodiamond.
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observation and control of blinking nitrogen vacancy centres in discrete Nanodiamonds
Nature Nanotechnology, 2010Co-Authors: Carlo Bradac, T Gaebel, Nishen Naidoo, Matthew Sellars, J Twamley, Louise J Brown, Amanda S Barnard, Taras Plakhotnik, Andrei V Zvyagin, J R RabeauAbstract:Nitrogen-vacancy colour centres in diamond can undergo strong, spin-sensitive optical transitions under ambient conditions, which makes them attractive for applications in quantum optics1, nanoscale magnetometry2,3 and biolabelling4. Although nitrogen-vacancy centres have been observed in aggregated detonation Nanodiamonds5 and milled Nanodiamonds6, they have not been observed in very small isolated Nanodiamonds7. Here, we report the first direct observation of nitrogen-vacancy centres in discrete 5-nm Nanodiamonds at room temperature, including evidence for intermittency in the luminescence (blinking) from the Nanodiamonds. We also show that it is possible to control this blinking by modifying the surface of the Nanodiamonds. Nitrogen-vacancy colour centres have been observed in discrete 5-nm Nanodiamonds at room temperature, and their blinking has been switched on and off by modifying the surface of the Nanodiamonds.