Functionalized electrospun nanofibrous microfiltration membranes for removal of bacteria and viruses

A novel nanofibrous microfiltration membrane system, fabricated from surface functionalized polyacrylonitrile (PAN) electrospun nanofibers, was demonstrated for the effective removal of bacteria and viruses from contaminated water. For membrane modification, dual-vinyl and tri-vinyl monomers were polymerized on the surface of the PAN electrospun nanofibers, which also improved the membrane mechanical properties due to the formation of a cross-linked. Meanwhile, the dual-vinyl monomer with an imidazolium cation resulted in positively charged electrospun PAN nanofibers, allowing the membrane to create not only 2–3 times higher permeation flux or lower pressure drop, but also 99.9999% retention of bacteria (e.g., Escherichia coli) and 99.99% retention of bacteriophage (e.g., MS2) during microfiltration when compared with commercial microfiltration membranes (e.g., 90% retention of MS2).