A new and simple green synthesis of non-toxic, eco-friendly silver nanoparticles by Gum Rosin and antibacterial activity study

Ag nanocolloid was prepared by green synthesis method using gum rosin as a capping and reducing agent and silver nitrate (AgNO3). The prepared Ag nanocolloid was characterized by using different analytical techniques such as UV-Vis, Dynamic light scattering (DLS), Zeta potential, Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), and Transmission electron microscopy (TEM). UV–visible spectra of the prepared Ag nanocolloid showed a sharp peak at ∼425 nm corresponding to the surface plasmon resonance (SPR) of the silver nanoparticles that were capped with gum rosin molecules. Ag nanoparticles with a diameter of 15-30 nm were observed in TEM and DLS analysis. A negative zeta potential value of −20.54 mV proved the stability of the rosin-stabilized silver nanoparticles. The Ag nanocolloid has shown an antibacterial activity against model organisms, a gram-negative Escherichia coli NCIM 2931 in Mueller–Hinton (MH) medium, which is hitherto unattempted up to now. In this study the ratio of Minimum Inhibitory (MIC) and Minimum Bactericidal Concentration (MBC) (MIC/MBC) was equal to 1, the green synthesized nanocolloid can be regarded as possessing an antibactericidal performance. The Ag nanocolloid with monodispersed Ag nanoparticles is considered to have potential applications in a variety of fields such as nanosensors, catalysis, electronic devices, and batteries.