Laser-assisted fabrication of silver quantum dots/polyaspartate polymer composite for antimicrobial applications

Abstract

Therapeutic utilization of biodegradable polymers for controlled drug delivery is a promising approach. The safety of this approach can be enhanced by using a green synthesis technique such as Pulsed Laser Ablation of solids in liquid (PLAL) for the fabrication of the nanoparticles. In this study, polyaspartate, a biodegradable polymer, was prepared by polycondensation of L-aspartic acid (PASP) and the AgNPs were synthesized in water, and solutions of PASP by ablation of silver plate with a Q-switched Nd: YAG laser at a wavelength of 1064 nm. The influence of PASP concentrations on the size and dispersity of the AgNPs were investigated. Antibacterial efficiency of the AgNPs was investigated on some bacterial strains by measuring the inhibition zones in agar using disc diffusion method. The nanoparticles were characterized by techniques such as XRD, TEM, UV–Vis, EDX, XRD, and XPS. The structural analysis revealed spherical shaped and well-dispersed silver nanoparticle quantum dots (Ag QDs) when silver metal was ablated in 0.5 mM of PASP. The Ag QDs/0.5 mM PASP sample showed a good inhibition effect against the bacterium Escherichia coli. The findings suggest that biofriendly PASP can successfully be employed in laser ablation for capping AgNPs, and the resultant material can be deployed as promising growth inhibitors against some pathogenic bacterial strains in relevant fields.