(244e) High Performance Electrospun Nanofiber Membranes for Protein Purifications
Membrane based cation-, anion-exchange and hydrophobic interaction chromatography (HIC) for protein purifications are often limited by the capacity in the flow through mode to remove impurities and aggregates, or capacity, selectivity and recovery in the bind-and-elute mode for protein fractionation. Electrospun nanofiber membranes are characterized by high surface to volume ratio and high permeability. Cationic and anionic ligands are grafted on the electrospun regenerated cellulose membrane substrates using UV-initiated and atom transfer radical polymerization. Static and dynamic binding capacities for model proteins such as BSA, IgG and lysozyme were determined under appropriate bind and elute buffer conditions. Static binding capacities in the order of several hundred mg/mL and dynamic binding capacities in the order of one hundred mg/mL can be obtained. In addition, thermo- and ionic strength responsive poly(vinylcaprolactam) (PVCL) ligands were grafted on the membrane surface for HIC applications. Compared to commercial HIC capacity in the range of 10-20 mg/mL, a much enhanced protein binding capacity was obtained due to the high surface-to-volume ratio of the electrospun membranes.