Antibacterial poly(D

L-lactide) (PDLLA) fibrous membranes were developed via electrospinning

followed by surface modification which involved plasma pretreatment

UV-induced graft copolymerization of 4-vinylpyridine (4VP) and quaternization of the grafted pyridine groups with hexylbromide. The success of modification with quaternized pyridinium groups on the PDLLA fibrous membranes was ascertained by X-ray photoelectron spectroscopy (XPS). The antibacterial activities of these membranes were assessed against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). The PDLLA fibrous membranes modified with quaternized pyridinium groups showed antibacterial efficiency against both bacteria as high as 99.999%. The results demonstrated that the antibacterial activity was based on the interaction of the positive charge of pyridinium group and negatively charged cell membrane of bacteria

resulting in loss of membrane permeability and cell leakage.