Crosslinked chitosan-guanidine polymeric thin film coated onto polypropylene non-woven fabric for excellent and permanent antibacterial properties

Wearing face masks made from non-woven fabrics is recommended as part of personal protective equipment and as a public health measure to prevent the spread of the coronavirus disease 2019 (COVID-19) pandemic. Enhancing these masks with antibacterial materials and increasing their durability are important. This study investigated the effectiveness of surface coating of polypropylene non-woven fabric (PPNWF) using antibacterial agents chitosan (CS) and polyhexamethylene guanidine hydrochloride (PHMG), with sodium tripolyphosphate (TPP) as the crosslinking agent. The CS-TPP-PHMG coated PPNWF surface was characterized using field emission scanning electron microscopy (FE-SEM), attenuated total reflection - Fourier transform infrared (ATR-FTIR) spectroscopy, and the PHMG release from the coated PPNWF surface over various immersion durations in water was also evaluated. The experimental results showed that the PPNWF surface coated with crosslinked CS-TPP-PHMG materials exhibited improved antibacterial capability against Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria. The CS-TPP-PHMG coated PPNWF material maintained excellent antibacterial properties against these bacteria after 24 h of water immersion.