N-halamine-decorated electrospun polyacrylonitrile nanofibrous membranes: characterization and antimicrobial properties

Microbial contamination of drinking water and air is an alarming phenomenon that has attracted increasing global attention. Although many advances in microbial disinfection have been made over the years, robust, rapid, inexpensive and field-deployable strategies are still urgently needed to address this public health issue. Herein we report the preparation of antimicrobial nanofibrous membranes, which involves incorporation of highly porous electrospun polyacrylonitrile (PAN) membranes with 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) by two different approaches, namely, blend electrospinning and soaking. The functionalized membranes were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and titrimetry, and their antimicrobial efficacies were evaluated against two bacteria (Klebsiella pneumoniae and Escherichia coli). The MC-decorated electrospun PAN membranes inactivated both bacterial strains within 2 min of contact time. Moreover, the MC-soaked PAN membrane showed excellent disinfection efficacy against aerosolized E. coli after an exposure of 30 min. The simplicity, cost-effectiveness, versatility, and scalability of the electrospinning process, together with the superior antimicrobial activity of N-halamines make it a promising solution for water disinfection, and for the inactivation of airborne microorganisms.