The surface chemistry and stability of gold nanoparticles prepared using methanol extract of Eucalyptus camaldulensis

Abstract

The development of nontoxic, clean techniques for synthesising metal nanoparticles such as gold has attracted increasing attention in recent years. Many reports have been published about the synthesis of gold nanoparticles using plant extracts. However, the stability of these prepared gold nanoparticles has not been investigated. In this research, the stability of gold nanoparticles prepared by Eucalyptus camaldulensis was investigated at different temperatures (4°C, 25°C and 45°C) for 8 weeks. Transmission electron microscopy and visible absorption spectroscopy confirmed the stability of gold nanoparticles during the storage period at the mentioned condition. In addition, Fourier transform–infrared spectroscopy was used to investigate the surface chemistry of gold nanoparticles prepared by the methanol extract of E. camaldulsis. The carboxyl group was characterised on the surface of the gold nanoparticles, and this functional group may have a critical role in the stability of gold nanoparticles prepared by the mentioned plant extract at different conditions. This functional group can be used for drug delivery of amino derivative drugs using gold nanoparticles.