The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

P T Kalaichelvan - One of the best experts on this subject based on the ideXlab platform.

  • biosynthesis of silver and Gold Nanoparticles using thermophilic bacterium geobacillus stearothermophilus
    Process Biochemistry, 2011
    Co-Authors: Mohammed A Fayaz, M Girilal, Mashihur Rahman, R Venkatesan, P T Kalaichelvan
    Abstract:

    Nanomaterials have assumed a great deal of importance as they often display unique and considerably modified physical, chemical and biological properties as compared to their counterparts of the macroscale. In this study, biogenic synthesis of silver and Gold Nanoparticles by Geobacillus stearothermophilus has been attempted. The exposure of G. stearothermophilus cell free extract to the metal salts leads to the formation of stable silver and Gold Nanoparticles in the solution. These Nanoparticles were characterized by UV–Vis spectra, FTIR, TEM, and XRD. The silver and Gold Nanoparticles have absorption maxima at 423 nm and 522 nm respectively. The TEM micrograph revealed the formation of polydispersed particles in the case of silver Nanoparticles and monodispersed particles with respect to the Gold Nanoparticles. High stability of the nanoparticle solution could be attributed to the secretion of certain capping proteins by the bacterium in the reaction mixture. The involvement of these proteins was confirmed by FTIR and SDS PAGE.

  • biosynthesis of silver and Gold Nanoparticles using thermophilic bacterium geobacillus stearothermophilus
    Process Biochemistry, 2011
    Co-Authors: Mohammed A Fayaz, M Girilal, Mashihur Rahman, R Venkatesan, P T Kalaichelvan
    Abstract:

    Nanomaterials have assumed a great deal of importance as they often display unique and considerably modified physical, chemical and biological properties as compared to their counterparts of the macroscale. In this study, biogenic synthesis of silver and Gold Nanoparticles by Geobacillus stearothermophilus has been attempted. The exposure of G. stearothermophilus cell free extract to the metal salts leads to the formation of stable silver and Gold Nanoparticles in the solution. These Nanoparticles were characterized by UV–Vis spectra, FTIR, TEM, and XRD. The silver and Gold Nanoparticles have absorption maxima at 423 nm and 522 nm respectively. The TEM micrograph revealed the formation of polydispersed particles in the case of silver Nanoparticles and monodispersed particles with respect to the Gold Nanoparticles. High stability of the nanoparticle solution could be attributed to the secretion of certain capping proteins by the bacterium in the reaction mixture. The involvement of these proteins was confirmed by FTIR and SDS PAGE.

Mohammed A Fayaz - One of the best experts on this subject based on the ideXlab platform.

  • biosynthesis of silver and Gold Nanoparticles using thermophilic bacterium geobacillus stearothermophilus
    Process Biochemistry, 2011
    Co-Authors: Mohammed A Fayaz, M Girilal, Mashihur Rahman, R Venkatesan, P T Kalaichelvan
    Abstract:

    Nanomaterials have assumed a great deal of importance as they often display unique and considerably modified physical, chemical and biological properties as compared to their counterparts of the macroscale. In this study, biogenic synthesis of silver and Gold Nanoparticles by Geobacillus stearothermophilus has been attempted. The exposure of G. stearothermophilus cell free extract to the metal salts leads to the formation of stable silver and Gold Nanoparticles in the solution. These Nanoparticles were characterized by UV–Vis spectra, FTIR, TEM, and XRD. The silver and Gold Nanoparticles have absorption maxima at 423 nm and 522 nm respectively. The TEM micrograph revealed the formation of polydispersed particles in the case of silver Nanoparticles and monodispersed particles with respect to the Gold Nanoparticles. High stability of the nanoparticle solution could be attributed to the secretion of certain capping proteins by the bacterium in the reaction mixture. The involvement of these proteins was confirmed by FTIR and SDS PAGE.

  • biosynthesis of silver and Gold Nanoparticles using thermophilic bacterium geobacillus stearothermophilus
    Process Biochemistry, 2011
    Co-Authors: Mohammed A Fayaz, M Girilal, Mashihur Rahman, R Venkatesan, P T Kalaichelvan
    Abstract:

    Nanomaterials have assumed a great deal of importance as they often display unique and considerably modified physical, chemical and biological properties as compared to their counterparts of the macroscale. In this study, biogenic synthesis of silver and Gold Nanoparticles by Geobacillus stearothermophilus has been attempted. The exposure of G. stearothermophilus cell free extract to the metal salts leads to the formation of stable silver and Gold Nanoparticles in the solution. These Nanoparticles were characterized by UV–Vis spectra, FTIR, TEM, and XRD. The silver and Gold Nanoparticles have absorption maxima at 423 nm and 522 nm respectively. The TEM micrograph revealed the formation of polydispersed particles in the case of silver Nanoparticles and monodispersed particles with respect to the Gold Nanoparticles. High stability of the nanoparticle solution could be attributed to the secretion of certain capping proteins by the bacterium in the reaction mixture. The involvement of these proteins was confirmed by FTIR and SDS PAGE.

Jayoung Jeong - One of the best experts on this subject based on the ideXlab platform.

  • subchronic inhalation toxicity of Gold Nanoparticles
    Particle and Fibre Toxicology, 2011
    Co-Authors: Jae Hyuck Sung, Ki Soo Jeon, Jin Uk Yoon, Moon Yong Song, Jayoung Jeong, Kyung Seuk Song, Jun Ho Ji, Yong-hyun Chung, Jung Duck Park, Hee Kyung Chang
    Abstract:

    Background Gold Nanoparticles are widely used in consumer products, including cosmetics, food packaging, beverages, toothpaste, automobiles, and lubricants. With this increase in consumer products containing Gold Nanoparticles, the potential for worker exposure to Gold Nanoparticles will also increase. Only a few studies have produced data on the in vivo toxicology of Gold Nanoparticles, meaning that the absorption, distribution, metabolism, and excretion (ADME) of Gold Nanoparticles remain unclear.

  • acute toxicity and pharmacokinetics of 13 nm sized peg coated Gold Nanoparticles
    Toxicology and Applied Pharmacology, 2009
    Co-Authors: Jinyoung Jeong, Mina Choi, Bong Hyun Chung, Jayoung Jeong
    Abstract:

    In general, Gold Nanoparticles are recognized as being as nontoxic. Still, there have been some reports on their toxicity, which has been shown to depend on the physical dimension, surface chemistry, and shape of the Nanoparticles. In this study, we carry out an in vivo toxicity study using 13 nm-sized Gold Nanoparticles coated with PEG (MW 5000). In our findings the 13 nm sized PEG-coated Gold Nanoparticles were seen to induce acute inflammation and apoptosis in the liver. These Nanoparticles were found to accumulate in the liver and spleen for up to 7 days after injection and to have long blood circulation times. In addition, transmission electron microscopy showed that numerous cytoplasmic vesicles and lysosomes of liver Kupffer cells and spleen macrophages contained the PEG-coated Gold Nanoparticles. These findings of toxicity and kinetics of PEG-coated Gold Nanoparticles may have important clinical implications regarding the safety issue as PEG-coated Gold Nanoparticles are widely used in biomedical applications.

Xing-jie Liang - One of the best experts on this subject based on the ideXlab platform.

  • size dependent radiosensitization of peg coated Gold Nanoparticles for cancer radiation therapy
    Biomaterials, 2012
    Co-Authors: X. Zhang, Xiu Shen, Di Wu, Jie Chen, Xing-jie Liang
    Abstract:

    Abstract Gold Nanoparticles have been conceived as a radiosensitizer in cancer radiation therapy, but one of the important questions for primary drug screening is what size of Gold Nanoparticles can optimally enhance radiation effects. Herein, we perform in vitro and in vivo radiosensitization studies of 4.8, 12.1, 27.3, and 46.6 nm PEG-coated Gold Nanoparticles. In vitro results show that all sizes of the PEG-coated Gold Nanoparticles can cause a significant decrease in cancer cell survival after gamma radiation. 12.1 and 27.3 nm PEG-coated Gold Nanoparticles have dispersive distributions in the cells and stronger sensitization effects than 4.8 and 46.6 nm particles by both cell apoptosis and necrosis. Further, in vivo results also show all sizes of the PEG-coated Gold Nanoparticles can significantly decrease tumor volume and weight after 5 Gy radiations, and 12.1 and 27.3 nm PEG-coated Gold Nanoparticles have greater sensitization effects than 4.8 and 46.6 nm particles, which can lead to almost complete disappearance of the tumor. In vivo biodistribution confirms that 12.1 and 27.3 nm PEG-coated Gold Nanoparticles are accumulated in the tumor with high concentrations. The pathology, immune response, and blood biochemistry indicate that the PEG-coated Gold Nanoparticles have not caused spleen and kidney damages, but give rise to liver damage and Gold accumulation. It can be concluded that 12.1 and 27.3 nm PEG-coated Gold Nanoparticles show high radiosensitivity, and these results have an important indication for possible radiotherapy and drug delivery.

R Venkatesan - One of the best experts on this subject based on the ideXlab platform.

  • biosynthesis of silver and Gold Nanoparticles using thermophilic bacterium geobacillus stearothermophilus
    Process Biochemistry, 2011
    Co-Authors: Mohammed A Fayaz, M Girilal, Mashihur Rahman, R Venkatesan, P T Kalaichelvan
    Abstract:

    Nanomaterials have assumed a great deal of importance as they often display unique and considerably modified physical, chemical and biological properties as compared to their counterparts of the macroscale. In this study, biogenic synthesis of silver and Gold Nanoparticles by Geobacillus stearothermophilus has been attempted. The exposure of G. stearothermophilus cell free extract to the metal salts leads to the formation of stable silver and Gold Nanoparticles in the solution. These Nanoparticles were characterized by UV–Vis spectra, FTIR, TEM, and XRD. The silver and Gold Nanoparticles have absorption maxima at 423 nm and 522 nm respectively. The TEM micrograph revealed the formation of polydispersed particles in the case of silver Nanoparticles and monodispersed particles with respect to the Gold Nanoparticles. High stability of the nanoparticle solution could be attributed to the secretion of certain capping proteins by the bacterium in the reaction mixture. The involvement of these proteins was confirmed by FTIR and SDS PAGE.

  • biosynthesis of silver and Gold Nanoparticles using thermophilic bacterium geobacillus stearothermophilus
    Process Biochemistry, 2011
    Co-Authors: Mohammed A Fayaz, M Girilal, Mashihur Rahman, R Venkatesan, P T Kalaichelvan
    Abstract:

    Nanomaterials have assumed a great deal of importance as they often display unique and considerably modified physical, chemical and biological properties as compared to their counterparts of the macroscale. In this study, biogenic synthesis of silver and Gold Nanoparticles by Geobacillus stearothermophilus has been attempted. The exposure of G. stearothermophilus cell free extract to the metal salts leads to the formation of stable silver and Gold Nanoparticles in the solution. These Nanoparticles were characterized by UV–Vis spectra, FTIR, TEM, and XRD. The silver and Gold Nanoparticles have absorption maxima at 423 nm and 522 nm respectively. The TEM micrograph revealed the formation of polydispersed particles in the case of silver Nanoparticles and monodispersed particles with respect to the Gold Nanoparticles. High stability of the nanoparticle solution could be attributed to the secretion of certain capping proteins by the bacterium in the reaction mixture. The involvement of these proteins was confirmed by FTIR and SDS PAGE.