Triethylamine induced synthesis of silver and bimetallic (Ag/Au) nanoparticles in glycerol and their antibacterial study

Formation of Ag nanoplates in the presence of glycerol/triethylamine/polyvinylpyrrolidone without using any external reducing agent is shown for the first time. This approach is a unique and size-controlled synthetic method for the preparation of Ag nanoplates. Results reveal that addition of triethylamine to the precursor reaction mixture plays an important role both as a reagent for initiation and accelerator to produce nanoparticles at room temperature in the presence of glycerol. The basicity of the reaction mixture results in the appearance of two strongly localized surface plasmon resonance peaks of Ag nanoplates, effectively indicating the steady transition from non-planar structure to planar structure as confirmed by UV–Vis and transmission electron microscope measurements. The antibacterial activity of Ag and bimetallic (Ag/Au) nanoparticles were tested against gram-negative and grampositive bacteria. The enhanced antibacterial activity was observed with bimetallic nanoparticles with equal concentration of silver.