Sapindus mukorossi aqueous fruit extract as reducing, capping and dispersing agents in synthesis of gold nanoparticles

A report is presented on the synthesis of gold nanoparticles (AuNPs) using aqueous extract of Sapindus mukorossi, a traditional medicinal plant in India. UV-visible spectroscopy analysis indicated the successful formation of AuNPs. The synthesised AuNPs were characterised with different techniques such as transmission electron microscopy (TEM), Fourier transforms infrared (FTIR) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX). TEM experiments showed that AuNPs were predominantly spherical and hexagonal in shape with an average size of 7.3 nm. FTIR spectroscopy revealed that AuNPs were functionalised with biomolecules that have primary amine group (-NH2), carbonyl group, -OH groups and other stabilising functional groups. Thermo gravimetric analysis (TGA) revealed the weight loss (13%) of AuNPs. FTIR, TGA and EDX together confirmed the presence of biomolecules bounded on the AuNPs. Cytotoxicity of the AuNPs was tested on two human cancer cell lines, HeLa and A549 and found to be non-toxic, which thus proved their biocompatibility.