Synthesis and characterization of electrospun PVA/Zn2+ metal composite nanofibers for lipase immobilization with effective thermal, pH stabilities and reusability.

Polyvinyl alcohol (PVA)/Zn2+ electrospun nanofibers that were a kind of polymer/ionic metal composite was successfully embedded in the hybrid fibers for the first time in the literature, due to chemical interactions between PVA and Zn2+. Also, the nanofibers were used as carriers for the first time in enzyme immobilization. The nanofibers were optimized and synthesized by electrospinning technique according to the operational parameters like as PVA concentration (%), Zn2+ concentration (%), voltage (kV), needle tip-collector distance (cm) and injection speed (ml/h). The morphology and structure of the nanofibers were characterized by SEM, XRD, ATR-FTIR and TGA. Lipase was immobilized on the nanofibers by adsorption and crosslinking methods. According to immobilization results, nanofiber enhanced enzyme stability properties like as thermal stability, pH stability and reusability. Lipase immobilized nanofiber protected 90% of its activity after 14 reuses.