Green synthesis of bacterial gold nanoparticles conjugated to resveratrol as delivery vehicles

Bio-directed synthesis of metal nanoparticles is gaining importance in view of their biocompatibility, low toxicity and eco-friendly characteristics. The present study describes the application of resveratrol conjugated gold nanoparticles as effective delivery vehicles. The green chemistry approach was used for the synthesis of gold nanoparticles by using the culture supernatant of Delftia sp. strain KCM-006. The synthesized gold nanoparticles were mono-dispersed, spherical in shape with an average size of 11.3 nm. They were found to be photoluminescent and crystalline in nature with a zeta potential of −25 mV, indicating their high stability. Resveratrol, an anticancer drug, was conjugated to these gold nanoparticles (RSV-AuNP). The cell viability and immunocytochemistry analysis with human lung cancer cell line (A549) demonstrated that RSV-AuNPs were 65% more effective as drug when compared to resveratrol alone. In vitro observations on the drug release from these nanoparticles exhibited pH dependency; the release was significant (95%) under acidic conditions (pH 5.2) when compared to physiological conditions (pH 7.4).