Sarbjeet Singh Gujral
Objective: synthesis of gold and silver nano-particles using leaf extracts of Catharanthus roseus, Datura metel and Azadirachta indica and Estimation of antimicrobial activity of silver nano-particles using disc diffusion method. Method: Green approach has been utilized for the synthesis of gold and silver nano-particles. Different aqueous plant extracts has been prepared which was then utilized for the biosynthesis of gold and silver nano-particles. Estimation for the synthesis of nano-particles were done using UV-Visible spectroscopy and Fourier- Transform infrared spectroscopy. Antimicrobial activity of silver nano-particles prepared using aqueous neem extract was investigated using disc diffusion method. Result: UV- Vis spectroscopy of prepared nano-particles was done which gave a peak at about 550 nm for gold nano-particles and around 430 nm for silver nano-particles. FTIR of collected nano-particles gave an idea about the type of bio-molecules which helped in the reduction of auric and silver salts into corresponding nano-particles. Anti-microbial activity of silver nano-particles showed that the nano-particles have better anti-microbial activity than 2% silver nitrate solution (kept as standard) when experiments were performed under similar conditions. Conclusion: Gold and silver nano-particles were successfully synthesized using greener approach and anti-microbial activity of silver nano-particles prepared using aqueous neem extract was estimated against 2% AgNO3 solution. Nano-particles gave better anti-microbial activity than Silver nitrate solution.
