Antioxidant, Antibacterial, and BSA Binding Properties of Curcumin Caffeate Capped Silver Nanoparticles Prepared by Greener Method

Abstract

A green method of silver nanoparticle (AgNP) preparation using curcumin caffeate (CCaf) as stabilizing/capping and reducing group is reported here. CCaf is prepared through esterification of curcumin and caffeic acid in presence of p‐toluene sulphonic acid as catalyst. CCaf facilitates production of AgNPs in aqueous medium and room temperature without any external reducing agents. The antioxidant, antibacterial and BSA binding interactions of these CCafAgNPs are evaluated. The antioxidant activity and the corresponding IC50 value for the CCafAgNPs is found to be comparable with ascorbic acid taken as standard antioxidant for the study. The results of bactericidal screening of CCafAgNPs are better compared to CCaf capping group and found to exhibit broad spectrum antibacterial property against Gram‐positive and Gram‐negative bacterial pathogens. In presence of CCafAgNPs the absorption spectra of BSA showed changes with increase in intensity around 280 nm of native BSA peak and appearance of a new band around 320 nm, indicating the possible binding interactions between BSA and CCafAgNPs.