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Peter J. Pauzauskie - One of the best experts on this subject based on the ideXlab platform.
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Photothermal effects during Nanodiamond synthesis from a carbon aerogel in a laser-heated diamond anvil cell
Diamond and Related Materials, 2018Co-Authors: Matthew J. Crane, Bennett E. Smith, Peter B. Meisenheimer, Xuezhe Zhou, E. James Davis, Rhonda M Stroud, Peter J. PauzauskieAbstract:Nanodiamonds have emerged as promising materials for quantum computing, biolabeling, and sensing due to their ability to host color centers with remarkable photostability and long spin-coherence times at room temperature. Recently, a bottom-up, high-pressure, high-temperature (HPHT) approach was demonstrated for growing Nanodiamonds with color centers from amorphous carbon precursors in a laser-heated diamond anvil cell (LH-DAC) that was supported by a near-hydrostatic noble gas pressure medium. However, a detailed understanding of the photothermal heating and its effect on diamond growth, including the phase conversion conditions and the temperature-dependence of color center formation, has not been reported. In this work, we measure blackbody radiation during LH-DAC synthesis of Nanodiamond from carbon aerogel to examine these temperature-dependent effects. Blackbody temperature measurements suggest that Nanodiamond growth can occur at 16.3 GPa and 1800 K. We use Mie theory and analytical heat transport to develop a predictive photothermal heating model. This model demonstrates that melting the noble gas pressure medium during laser heating decreases the local thermal conductivity to drive a high spatial resolution of phase conversion to diamond. Finally, we observe a temperature-dependent formation of nitrogen vacancy centers and interpret this phenomenon in the context of HPHT carbon vacancy diffusion.
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photothermal effects during Nanodiamond synthesis from a carbon aerogel in a laser heated diamond anvil cell
arXiv: Materials Science, 2017Co-Authors: Matthew J. Crane, Bennett E. Smith, Peter B. Meisenheimer, Xuezhe Zhou, Rhonda M Stroud, Peter J. Pauzauskie, James E DavisAbstract:Nanodiamonds have emerged as promising materials for quantum computing, biolabeling, and sensing due to their ability to host color centers with remarkable photostability and long spin-coherence times at room temperature. Recently, a bottom-up, high-pressure, high-temperature (HPHT) approach was demonstrated for growing Nanodiamonds with color centers from amorphous carbon precursors in a laser-heated diamond anvil cell (LH-DAC) that was supported by a near-hydrostatic noble gas pressure medium. However, a detailed understanding of the photothermal heating and its effect on diamond growth, including the phase conversion conditions and the temperature-dependence of color center formation, has not been reported. In this work, we measure blackbody radiation during LH-DAC synthesis of Nanodiamond from carbon aerogel to examine these temperature-dependent effects. Blackbody temperature measurements suggest that Nanodiamond growth can occur at 16.3 GPa and 1800 K. We use Mie theory and analytical heat transport to develop a predictive photothermal heating model. This model demonstrates that melting the noble gas pressure medium during laser heating decreases the local thermal conductivity to drive a high spatial resolution of phase conversion to diamond. Finally, we observe a temperature-dependent formation of nitrogen vacancy centers and interpret this phenomenon in the context of HPHT carbon vacancy diffusion using CB{\Omega} theory.
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 behavior and reduction of copper ii acetate on the surface of detonation Nanodiamond with well defined surface chemistry
Carbon, 2016Co-Authors: Kostiantyn Turcheniuk, Vadym MochalinAbstract:Abstract We report a novel wet chemistry route to metal coated Nanodiamond particles. The technique includes adsorption of copper (II) acetate followed by reduction with hydrazine. To understand factors influencing the adsorption of the copper salt, Nanodiamonds with different and well defined chemistries have been synthesized. The interaction of copper ions with NDs was studied by means of adsorption isotherms revealing different behavior depending on Nanodiamond surface chemistry. Reduction of copper ions adsorbed on Nanodiamond yields Nanodiamond particles encapsulated into copper shells (ND@Cu). Using this technique, we can achieve up to 7.5 wt% of metallic copper on the Nanodiamond surface, which is 3 times higher than reported so far. Synthesized copper coated Nanodiamond particles will be used as a convenient nanofiller to reinforce copper and other metals with Nanodiamond.
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adsorption of drugs on Nanodiamond toward development of a drug delivery platform
Molecular Pharmaceutics, 2013Co-Authors: Vadym Mochalin, Amanda Pentecost, Ioannis Neitzel, 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, Amanda Pentecost, Ioannis Neitzel, 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...
Matthew J. Crane - One of the best experts on this subject based on the ideXlab platform.
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Photothermal effects during Nanodiamond synthesis from a carbon aerogel in a laser-heated diamond anvil cell
Diamond and Related Materials, 2018Co-Authors: Matthew J. Crane, Bennett E. Smith, Peter B. Meisenheimer, Xuezhe Zhou, E. James Davis, Rhonda M Stroud, Peter J. PauzauskieAbstract:Nanodiamonds have emerged as promising materials for quantum computing, biolabeling, and sensing due to their ability to host color centers with remarkable photostability and long spin-coherence times at room temperature. Recently, a bottom-up, high-pressure, high-temperature (HPHT) approach was demonstrated for growing Nanodiamonds with color centers from amorphous carbon precursors in a laser-heated diamond anvil cell (LH-DAC) that was supported by a near-hydrostatic noble gas pressure medium. However, a detailed understanding of the photothermal heating and its effect on diamond growth, including the phase conversion conditions and the temperature-dependence of color center formation, has not been reported. In this work, we measure blackbody radiation during LH-DAC synthesis of Nanodiamond from carbon aerogel to examine these temperature-dependent effects. Blackbody temperature measurements suggest that Nanodiamond growth can occur at 16.3 GPa and 1800 K. We use Mie theory and analytical heat transport to develop a predictive photothermal heating model. This model demonstrates that melting the noble gas pressure medium during laser heating decreases the local thermal conductivity to drive a high spatial resolution of phase conversion to diamond. Finally, we observe a temperature-dependent formation of nitrogen vacancy centers and interpret this phenomenon in the context of HPHT carbon vacancy diffusion.
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photothermal effects during Nanodiamond synthesis from a carbon aerogel in a laser heated diamond anvil cell
arXiv: Materials Science, 2017Co-Authors: Matthew J. Crane, Bennett E. Smith, Peter B. Meisenheimer, Xuezhe Zhou, Rhonda M Stroud, Peter J. Pauzauskie, James E DavisAbstract:Nanodiamonds have emerged as promising materials for quantum computing, biolabeling, and sensing due to their ability to host color centers with remarkable photostability and long spin-coherence times at room temperature. Recently, a bottom-up, high-pressure, high-temperature (HPHT) approach was demonstrated for growing Nanodiamonds with color centers from amorphous carbon precursors in a laser-heated diamond anvil cell (LH-DAC) that was supported by a near-hydrostatic noble gas pressure medium. However, a detailed understanding of the photothermal heating and its effect on diamond growth, including the phase conversion conditions and the temperature-dependence of color center formation, has not been reported. In this work, we measure blackbody radiation during LH-DAC synthesis of Nanodiamond from carbon aerogel to examine these temperature-dependent effects. Blackbody temperature measurements suggest that Nanodiamond growth can occur at 16.3 GPa and 1800 K. We use Mie theory and analytical heat transport to develop a predictive photothermal heating model. This model demonstrates that melting the noble gas pressure medium during laser heating decreases the local thermal conductivity to drive a high spatial resolution of phase conversion to diamond. Finally, we observe a temperature-dependent formation of nitrogen vacancy centers and interpret this phenomenon in the context of HPHT carbon vacancy diffusion using CB{\Omega} theory.
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, Amanda Pentecost, Ioannis Neitzel, 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, Amanda Pentecost, Ioannis Neitzel, 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.
Huancheng Chang - One of the best experts on this subject based on the ideXlab platform.
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tracking the engraftment and regenerative capabilities of transplanted lung stem cells using fluorescent Nanodiamonds
Nature Nanotechnology, 2013Co-Authors: Yankai Tzeng, Huancheng Chang, Weiwei Chang, Chian Cheng, Yung Kuo, Chinhsiang ChienAbstract:Lung stem/progenitor cells are potentially useful for regenerative therapy, for example in repairing damaged or lost lung tissue in patients. Several optical imaging methods and probes have been used to track how stem cells incorporate and regenerate themselves in vivo over time. However, these approaches are limited by photobleaching, toxicity and interference from background tissue autofluorescence. Here we show that fluorescent Nanodiamonds, in combination with fluorescence-activated cell sorting, fluorescence lifetime imaging microscopy and immunostaining, can identify transplanted CD45(-)CD54(+)CD157(+) lung stem/progenitor cells in vivo, and track their engraftment and regenerative capabilities with single-cell resolution. Fluorescent Nanodiamond labelling did not eliminate the cells' properties of self-renewal and differentiation into type I and type II pneumocytes. Time-gated fluorescence imaging of tissue sections of naphthalene-injured mice indicates that the fluorescent Nanodiamond-labelled lung stem/progenitor cells preferentially reside at terminal bronchioles of the lungs for 7 days after intravenous transplantation.
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mass production and dynamic imaging of fluorescent Nanodiamonds
Nature Nanotechnology, 2008Co-Authors: Yi Ren Chang, Yankai Tzeng, Kowa Chen, Chunchieh Chang, Dungsheng Tsai, Chicheng Fu, Chiayi Fang, Huancheng ChangAbstract:Fluorescent Nanodiamond is a new nanomaterial that possesses several useful properties, including good biocompatibility1, excellent photostability1,2 and facile surface functionalizability2,3. Moreover, when excited by a laser, defect centres within the Nanodiamond emit photons that are capable of penetrating tissue, making them well suited for biological imaging applications1,2,4. Here, we show that bright fluorescent Nanodiamonds can be produced in large quantities by irradiating synthetic diamond nanocrystallites with helium ions. The fluorescence is sufficiently bright and stable to allow three-dimensional tracking of a single particle within the cell by means of either one- or two-photon-excited fluorescence microscopy. The excellent photophysical characteristics are maintained for particles as small as 25 nm, suggesting that fluorescent Nanodiamond is an ideal probe for long-term tracking and imaging in vivo, with good temporal and spatial resolution.
