Good use of fruit wastes: eco-friendly synthesis of silver nanoparticles, characterization, BSA protein binding studies

A simple and eco-friendly methodology for the green synthesis of silver nanoparticles (AgNPs) using a mango seed extract was evaluated. The AgNPs were characterized by ultraviolet-visible spectrophotometry, Fourier transform infrared spectroscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The interaction between the green synthesized AgNPs and bovine serum albumin (BSA) in an aqueous solution at physiological pH was examined by fluorescence spectroscopy. The results confirmed that the AgNPs quenched the fluorophore of BSA by forming a ground state complex in aqueous solution. This fluorescence quenching data were also used to determine the binding sites and binding constants at different temperatures. The calculated thermodynamic parameters (Delta G degrees, Delta H degrees and Delta S degrees) suggest that the binding process occurs spontaneously through the involvement of electrostatic interactions. The synchronous fluorescence spectra showed a blue shift, indicating increasing hydrophobicity. Copyright (C) 2015 John Wiley & Sons, Ltd.