Bactericidal coating of paper towels via sustainable biosynthesis of silver nanoparticles using Ocimum sanctum leaf extract

The present study reports the effective impregnation of silver nanoparticles (AgNPs) biosynthesized using Ocimum sanctum leaf extract onto conventional tissue paper for the inhibition of hospital borne pathogenic bacterial growth. The AgNPs biosynthesised using the leaf extract had face centered cubic lattice structure, nano scale dimensions, biocompatible coating of plant proteins and an absorbance maximum at 438 nm. Further, these nanoparticles were used to engineer tissue paper towels under conditions akin to room temperature. The presence of nanoparticles on the tissue paper filaments were confirmed using SEM analysis. Detailed analysis using XRD and FTIR indicated the presence of AgNPs on the paper fibres and the appreciable amounts of bio-active functional groups on the modified tissue paper when compared to the conventional ones. The bioactive layers aid the firm adherence of bacterial cell wall proteins and there after the silver particles extend their bactericidal action on the attached bacteria. The antibacterial activity of the nano-engineered tissue paper towels were tested against common gram positive and gram negative pathogens. Further, cytotoxicity evaluation using MTT assay revealed that the AgNPs coated paper towels does not pose any unintended adverse effects on fibroblast cell lines. These results highlight that biogenic AgNPs coated paper towels are cost effective, eco-friendly and wholesome alternative for the conventional paper towels and can be an effective sanitizing product for decreasing the risk of health associated infections.