Synthesis of Annona glabra Mediated Silver Nanoparticles, their Photocatalysis and Toxicity on Daphnia magna

Abstract

This work reports the synthesis of silver nanoparticles (AgNPs) using the leaf extract of Annona glabra as a green synthetic route and assessment of its photocatalytic property using methelyne blue as a model dye and toxic effect against an aquatic model, Daphnia magna. Leaf extract prepared at 100 ºC, 1% plant extract, 1 mM of AgNO₃, 3 h incubation time were optimized for the synthesis of AgNPs. Surface plasmon resonance peak of AgNPs laid around 419 nm. Spherical nanoparticles were in the size ranges 50-80 and 110-195 nm. Biomolecules were present as capping agents on AgNPs. AgNPs have cubic face centered lattice structure and the average particle size as calculated using Debye-Scherrer formula is 55 nm. Green synthesized AgNPs reduced the absorbance of methelyne blue dye by 89% in 3 h showing prominent photocatalytic activity. The EC₅₀ of AgNPs was found to be 1.78 ± 0.20 mg/L against Daphnia magna showing a lower toxicity than silver ions.