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bioRxiv · 10.1101/164103

Exploration of Western Himalayan region for identification of gold nanoparticles synthesizing bacteria

Thakur, R. K.·Shirkot, P.
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Abstract

The development of eco-friendly methods for the synthesis of nanomaterial shape and size is an important area of research in the field of nanotechnology. In present study an indigenous bacterial strain GPI-1 has been isolated from a local gold mine Khaltunala. It was characterized morphological, biochemically and also by using 16S rrna gene technology and was identified as Bacillus flexus GPI-1, the phylogeny of this bacterial strain was determined using various bioinformatics tools viz BLASTn and MEGA 5.0. To achieve maximum invitro gold nanoparticles synthesis various parameters such as pH, incubation temperature, incubation time period and wavelength were optimized as 6.8, 37{degrees}C, 36 hrs, 560 nm respectively. Stable and cubical gold nanoparticles (GNPs) formation with 40-45 nm dimensions were synthesized successfully under invitro conditions upon exposure of gold chloride trihydrates (HAuCl4) solution to the supernatant of Bacillus flexus strain GPI-1. These gold nanoparticles have been characterized by Transmission electron microscope, Fourier transform infrared spectroscopy (FTIR). Thus in the present study successful biosynthesis method of stable and cubical gold nanoparticles in the size range of 12-30 nm using this efficient Bacillus flexus GPI-1 strain. Thus in the present study leading to development of an easy bioprocess for synthesis of GNPs of desired size and shape, has been reported and this green route of biosynthesis of GNPs is a simple, economically viable and an eco-friendly process. The use of gold nanoparticles in biomedical research like X-ray computed tomography and magnetic resonance imaging, cancer research, drug delivery applications.

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Thakur, R. K., Shirkot, P.. 2017-07-15. Exploration of Western Himalayan region for identification of gold nanoparticles synthesizing bacteria. https://doi.org/10.1101/164103

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