The Hydroxyapatite Nanowires as High Loading Substrate for Immobilization of Dextranase by Crosslinking Method

Abstract

Abstract In this work, dextranase was immobilized on the surface of hydroxyapatite nanowire through covalent cross-linking method. The as-prepared HAPNWs-NH2@dextranase was characterized by FE-SEM, XRD, TGA and FT-IR spectra analysis illustrated that the successful immobilization of dextranase by crosslinking method. The performance of HAPNWs-NH2@dextranase was studied and contrasted to free dextranase such as catalytic activity, loading capacity, kinetic constant, thermal and pH stability, storage stability and reusability. Compared with the free enzyme, HAPNWs-NH2@dextranase showed higher enzyme activity at higher thermal stability (92.28% vs 33.08% at 70°C) and pH stability (93.17% vs 57.78% at pH 7.0). The loading capacity of dextranase on HAPNWs-NH2@dextranase was higher as 868.2 mg·g− 1. HAPNWs-NH2@dextranase retained 83.38% of its initial activity after 12 cycles. It indicated that the HAPNWs-NH2@dextranase could have excellent performance in the industry fields.