Non-enveloped virus reduction with quaternized chitosan nanofibers containing graphene

Membranes are an accepted technology for water purification. Membrane filtration can remove pathogens, including bacteria and viruses, by size. For small viruses that can have a diameter <25nm, removal by size leads to large membrane areas, high transmembrane pressures, low water flux, and frequent changing of membranes. In this work, we discovered that electrospun nanofibers made of chitosan and functionalized with a quaternary amine (HTCC) have the ability to adsorb a model non-enveloped virus, porcine parvovirus (PPV). To improve the virus removal of HTCC, we added graphene. Graphene both enhanced the ability to form nanofibers with HTCC and improved the virus removal. The hydrophobicity of graphene and the high charge of the HTCC create a system that can bind 95% of PPV. The HTCC/graphene nanofibers could be incorporated into microfiltration membranes and remove virus by adsorption. This would create a low pressure system that is more likely to benefit areas in need of fresh water.