Nano-silver from plant extract
doi:10.1038/nindia.2018.74 Published online 17 June 2018
Chemists have developed an eco-friendly protocol for biosynthesis of silver nanoparticles – in the size range 100-300 nanometre – using the root extract of the plant Curculigo orchioides, commonly known as kali musli across India1.
The researchers report that in an aqueous solution of the root extract of C. orchioides, silver ions are reduced to zero-valent silver and eventually stabilize as silver nanoparticles.
Due to its unique electronic, optical, chemical and biochemical properties, nano-silver is variously used in spectrally-selective coating for solar energy, absorption electrical batteries, antimicrobial agents for safe water, food packaging and wound dressing. Scientists have long been exploring eco-friendly ways to synthesize them.
Sushma Dave of Jodhpur Institute of Engineering & Technology and Sunita Kumbhat of Jai Narain Vyas University, Jodhpur – both in Rajasthan – report that this extracellular bio-nanosynthesis route using renewable plant resources "represents an environmentally benign, clean, green and rapid approach to nano particle synthesis”. X-ray diffraction analyses and atomic force microscopy confirmed that the particles thus prepared displayed all characteristic features of nano size silver.
At room temperature the reaction time for synthesis of these nanoparticles was 40 minutes, much faster than the microbe-mediated synthesis yielding spherical silver nanoparticles, the report says. The researchers say the biogenic nanoparticles can be used for various biomedical, pharmaceutical and biotechnological commercial applications.
1. Dave, S. & Kumbhat, S. Electrochemical and spectral characterization of silver nanoparticles synthesized employing root extract of Curculigo orchioides. Ind. J. Chem. Technol. 25, 201-207 (2017)