Green Synthesis Of Gold Nanoparticles For controlled Delivery

Abstract

Gold nanoparticles (AuNPs) have been synthesized by green method using chitosan as a reducing/capping agent. We designed a biocompatible carrier for controlled release of hydrophobic drugs. The designed carrier was prepared by using single oil-in-water (O/W) emulsion. The resulting AuNPs were characterized by UV–Vis spectroscopy (UV–Vis) and Fourier transform infrared spectroscopy (FTIR). The transmission electron microscopy (TEM) studies indicate the spherical nature of drug loaded nanoparticles with the size of 50nm while the average particle size of AuNPs is found to be 2-3nm. The chitosan capped AuNPs showed a surface plasmon resonance at 526nm. The FTIR spectra suggest that the amine group is mainly responsible for the reduction of tetrachloroauric acid and capping the AuNPs. The controlled release of rifampicin (RIF) was investigated by in vitro studies using phosphate buffer saline (PBS) at pH=7.4. The loading efficiency of drug molecule was found to be 71%. The encapsulated drugs were released at 37 °C temperature. The results have been fit into various mechanistic models and it is found that the Higuchi model fits in to the release behavior of RIF. Further, the antibacterial activity of RIF loaded nanoparticles was examined by Gram +ve (bacillus subtils) and Gram -ve (Pseudomonas aeruginosa) bacteria. The application of similar drug loaded nanocarrier for treating other diseases like cancer can also be investigated.