Enhanced antimicrobial performance of single-use polyamide 56 nanofiber membranes modified with chitosan, reactive dyes, and poly(hexamethylene biguanide) (PHMB) for biological waste treatments

Abstract

Polyamide 56 (PA56), derived from renewable resources like wheat and corn via microbial fermentation, presents a sustainable alternative to traditional petrochemical-based polymers and has gained attention for its versatility in various fields. This study explores the antibacterial properties of bio-nylon nanofibers through fabrication and modification processes. PA56 nanofiber membrane was initially fabricated using electrospinning technology. These membranes were then modified with chitosan (CS), forming PA56-CS membranes, and further enhanced with Reactive dyes (Reactive Green 19, RG19 and Reactive Red 141, RR141) to produce PA56-CS-DYE membranes. Poly(hexamethylene biguanide) (PHMB), a positively charged polymer, was subsequently bonded to these membranes, resulting in PA56-CS-DYE-PHMB nanofiber membranes. Comprehensive physical characterizations using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) were conducted alongside qualitative and quantitative antibacterial assays against E. coli. The PA56-CS-RR141-PHMB nanofiber membrane exhibited exceptional antibacterial efficiency (AE), exceeding 97 %, indicating strong potential for biological waste treatment and related applications. However, the high antibacterial performance of these membranes is primarily suited for single-use systems, as their efficacy diminishes with repeated use, making them ideal for immediate and short-term applications in healthcare and environmental settings.