Green synthesis of silver nanoparticles using Coffea arabica seed extract and its antibacterial activity
Vivek Dhand1, L Soumya2, S Bharadwaj3
1Center for Nanoscience and Technology, IST, JNTUH, Kukatpally, Hyderabad, 500085 AP, India; Centre for Knowledge Management of Nanoscience and Technology, 12-5-32/8, Vijayapuri Colony, Tarnaka, 500017 AP, India; Department of Mechanical Engineering, College of Engineering, Kyung Hee University, 446-701 Yongin, Republic of Korea.
Abstract:
A novel green source was opted to synthesize silver nanoparticles using dried roasted Coffea arabica seed extract. Bio-reduction of silver was complete when the mixture (AgNO3+extract) changed its color from light to dark brown. UV-vis spectroscopy result showed maximum adsorption at 459 nm, which represents the characteristic surface plasmon resonance of nanosilver. X-ray crystal analysis showed that the silver nanoparticles are highly crystalline and exhibit a cubic, face centered lattice with characteristic (111), (200), (220) and (311) orientations. Particles exhibit spherical and ellipsoidal shaped structures as observed from TEM. Composition analysis obtained from SEM-EDXA confirmed the presence of elemental signature of silver. FTIR results recorded a downward shift of absorption bands between 800-1500 cm(-1) indicting the formation of silver nanoparticles. The mean particle size investigated using DLS was found to be in between 20-30 nm respectively. Anti-bacterial activity of silver nanoparticles on E. coli and S. aureus demonstrated diminished bacterial growth with the development of well-defined inhibition zones.
