Antibacterial activity of water soluble dye capped zinc oxide nanoparticles synthesised from waste Zn–C battery

Abstract

Antibacterial activity of functionalized ZnO nanoparticles synthesized from waste Zn–C battery by microwave method was investigated, water soluble 1-(carboxymethyl)-4-[(E)-2-(3-methoxy-4-methylphenyl)ethenyl] pyridin-1-ium photosensitizer was used as capping agent to control the size of nanoparticle. The characterization of the samples was done with the help of UV–visible spectroscopy, FTIR, SEM–EDS and XRD. The nanoparticles have hexagonal wurtzite structure with a mean diameter of 19.7 nm for 3% dye capped nanoparticle and 30.6 nm for uncapped nanoparticle and are composed by a mixture of small crystallites and disordered ZnO particles. Capped ZnO nanoparticles showed high antibacterial (tested on E. coli and B. subtilis) activities compared to that of uncapped nanoparticles under the same experimental conditions. This novel water soluble dye capped ZnO nanoparticles emerged as excellent antibacterial agent, the results show minimum inhibitory concentration of 0.39 and 1.56 for B. subtilis and E. coli and highest zone of inhibition was at concentration of 5 mg/ml. The bioactivity showed dye capped nanoparticle to be new class of antibacterial agent.