Plant extract mediated silver nanoparticles by concentrated sunlight and their antibacterial and cytotoxic activities

Abstract

Here we report the synthesis of silver nanoparticles (AgNPs) under concentrated sunlight by using a newly designed solar system. In the study, AgNPs synthesized by using different plant extracts of Ginko biloba (Gb), Alpinia officinarum (Ao), Foeniculum vulgare (Fv) and Cassia angustifolia (Ca) were characterized by different techniques. The antibacterial activity of the AgNPs was determined by agar diffusion assay. TEM analysis revealed the spherical nanoparticles with average size of 26, 23,44 and 32 nm in diameter for Gb, Ao, Fv and Ca AgNPs, respectively. Also, we found that the AgNPs were not cytotoxic at the concentration of 2.5 µg/mL. We also revealed that Ca AgNPs showed the highest antibacterial activity against S. aureus with inhibition zone of 15.27 mm. All in all, the results indicated that the formation of AgNPs was achieved in less than 1 h without any energy consumption in the solar system with concentrated sunlight.