Reusable anionic sulfonate functionalized nanofibrous membranes for cellulase enzyme adsorption and separation.

Poly (vinyl alcohol-co-ethylene) nanofibrous membranes (PVA-co-PE NFM) were successfully modified by sodium-3-sulfobenzoate to become negatively charged with sulfonate groups, and the sulfonated (PVA-co-PE) nanofiber membrane SS (PVA-co-PE NFM) was used in non-covalent adsorption of cellulases via electrostatic attraction. The modified NFM showed excellent adsorption to the enzyme molecules due to the incorporated static charge interaction with the fibers, high open-porosity and ultrahigh surface areas of the nanofibers. Such unique morphology and chemical structures lead to the adsorption capacity of 130 mg g-1 and reusability for 5 cycles without significant change in catalytic functions. The morphology changes of the nanofibrous membranes were observed by using a scanning electron microscopy, and chemical structures of the membranes were characterized by using FTIR and water contact angle measurements. SS (PVA-co-PE NFM) is a promising solid support media for enzyme immobilization, and the immobilized enzymes can be applied in industrial applications.