Adsorption of a non-enveloped mammalian virus to functionalized nanofibers

In the pursuit of finding superior methods to remove pathogens from drinking water, this study examines the adsorption of a non-enveloped, mammalian virus to highly charged nanofibers. N-[(2-Hydroxyl-3-trimethylammonium) propyl] chitosan (HTCC) nanofibers were synthesized by the addition of a quaternary amine to chitosan. HTCC was blended with polyvinyl alcohol (PVA) to produce nanofibers by electrospinning. The nanofibers were stabilized against water by crosslinking with glutaraldehyde. When studied in the range of 100–200 nm in diameter, larger fibers were able to adsorb about 90% more virus than smaller fibers. The kinetics of the adsorption was modeled with pseudo-first order kinetics and equilibrium was achieved in as little as 10 min. Equilibrium adsorption was modeled with the Freundlich isotherm with a Freundlich constant of 1.4. When the Freundlich constant deviates from 1, this demonstrates that there is heterogeneity at the adsorption surface. The heterogeneity likely occurs at the nanofiber surface since a polymeric blend of two polymers was used to electrospin the nanofibers. The model mammalian virus, porcine parvovirus (PPV), has a fairly homogeneous, icosahedral protein capsid available for adsorption. The fast adsorption kinetics and high capacity of the nanofibers make HTCC/PVA a potential filter material for the removal of pathogens from drinking water.