Essay on Gold Nano Particles - 551 Words

In recent years Nano sized materials play the significant role in science and technology due to their unique shape, size, peculiar properties and potential applications. Metal nanoparticles, which possess considerable electronic, chemical and optical [1, 2] properties, are different from those of the bulk materials. Among the several metal nano particles gold (Au) nanoparticles have attracted rigorous consideration for their numerous applications in catalytic , sensing, imaging, diagnostics [3-6], tunable surface Plasmon resonance, surface enhanced Raman scattering, electrical, magnetic, thermal conductivity chemical and bio stability and anti-bacterial activity [7-13]. Besides, Gold nano particles have widely been used as the platform†¦show more content†¦It is exuded from the bark of cochlospermum gossypium (bixaceae family) and it is largely collected by tribes. The primary structure of gum kondagogu is made up of sugars such as galactose, aabinose, mannose, glucose, gluc onic acid, rhamnose and galactoronic acid with sugar linkage of (1→2) ÃŽ ²-D-Gal p, (1→4) ÃŽ ²-D-Glc p, (1→6) ÃŽ ²-D-Gal p, 4-O-Me-ÃŽ ±-D-Glc p, (1→2) ÃŽ ±-L-Rha (29). Gum kondagogu is an acidic gum with major functional groups and identified in the gum is acetyl, hydroxyl, carboxylic acid and carbonyl groups. Gold has usually been regarded to be inactive as a catalyst. But gold in the form of nanoparticles shows excellent catalytic activity towards several chemical reactions (30). Nitro phenols are environmental poisons due to their toxicity (31) and inhibitory nature. In addition, Nitro phenols have highly solubility and stability in water (32). Due to this reason the reduction of 4-NP in to 4-AP is prominent. Sodium borohydride is a strong reducing agent, but, it has no ability to reduce the nitro phenol. NaBH4 is not effective in this reaction except provided with some catalyst to reduce the kinetic barrier of the reaction. A variety of catalysts were used in the past and, recently, pt (33), Ag (34) nanoparticles have been used for the same purpose. In this study the green synthesis of gold nano particles made by gum kondagogu is a core subject. This gum acts as a reducing and stabilizing agent. We studied the synthesis of AuNPs and theirShow MoreRelatedGold Of Bacterial Detection By W illiam Farrell980 Words   |  4 PagesGOLD IN BACTERIAL DETECTION By William Farrell The purpose of this Poster is to inform you of the treatment of certain bacterial strains using a combination of ‘pulsed laser energy and absorbing nanoparticles selectively attached to the bacterium.’ (2006, The Biophysical Society) INTRO Nanotechnology has expanded human capabilities to perform tasks by manufacturing nanostructured materials with certain properties, properties which we use in many different areas. 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