Antibacterial activity of quaternized chitosan modified nanofiber membrane

Abstract

The electrospinning PAN nanofiber membrane (P-CN) was hydrolysed to convert carboxylic groups as reaction sites and covalently graft chitosan molecule. The chitosan derivatives with quaternary ammonium groups exerted greater efficiency against bacteria as compared to pure chitosan. Hence, the chitosan modified membrane (P-CS), can be functionalized with quaternary amine (i.e., glycidyl trimethyl ammonium chloride, GTMAC) to form quaternized chitosan nanofiber membrane (designated as P-HTCC) under various conditions (acidic, neutral, and alkaline). N-quaternized derivatives of chitosan modified membrane (N-HTCC) showed 72% and 60% degree of quaternization (DQ) under acidic and neutral conditions, respectively. Under alkaline condition, additional quaternization of N, O-HTCC via its amino and hydroxyl groups, has improved up to 90% DQ of the chitosan. The antibacterial activity of the quaternized chitosan modified membrane prepared from acetic acid medium is stronger than that prepared from water and alkaline media. Also, antibacterial activity of quaternized chitosan is stronger than chitosan modified membrane against E. coli. The microbiological assessments showed that the water-stable P-HTCC nanofiber membrane under modification in acidic medium exerted antibacterial activity up to 99.95% against E. coli. Therefore, the P-HTCC membrane exhibited high potential to be integrated into microfiltration membrane to effectively disinfect E. coli.

Keywords: Antibacterial activity; E. coli; Electrospinning; Nanofiber membrane; Quaternized chitosan.