Sunlight-induced green synthesis of silver nanoparticles using aqueous leaf extract of Polyalthia longifolia and its antioxidant activity

In the present work, AgNPs was synthesized using the aqueous extract of Polyalthia longifolia which was monitored by UV–vis spectroscopy at regular time interval. The optimum conditions for AgNPs biosynthesis were found to be 30 min sunlight exposure, 2.0% (v/v) AEP inoculum dose and 4.0 mM AgNO3 concentration. SEM and TEM analysis confirmed the presence of anisotropic AgNPs with average size 13.9 nm. The X-Ray techniques confirmed that the AgNPs were crystallized in the face-centered cubic lattice. FTIR analysis confirmed the involvement of functional groups in the AgNPs synthesis. The AgNPs thus obtained showed sufficient antioxidant activity.