Magnetic PAES ‐ COOH Nanofibers as Efficient and Reusable Carriers for Glucose Oxidase Immobilization

ABSTRACT Free glucose oxidase (GOx) exhibits high specificity and catalytic efficiency under mild conditions; however, its practical application is limited by poor stability and reusability. In this study, a magnetic nanofiber carrier was fabricated from carboxyl‐functionalized polyaryl ether sulfone (PAES‐COOH) nanofibers via a facile acid precipitation method. The preparation parameters of the magnetic PAES‐COOH nanofiber carrier (MNPAES) and the immobilization conditions for GOx were systematically optimized. The structural and surface properties of PAES‐COOH nanofibers and MNPAES were characterized by SEM, FT‐IR, XPS, 1 H NMR, GPC, and BET analyses. Compared with pristine nanofibers, MNPAES exhibited an increased specific surface area (from 9.5 to 21.1 m 2 /g) and an enlarged average pore size (from 2.3 to 123 nm), facilitating enzyme immobilization. GOx immobilized on MNPAES (GOx@MNPAES) showed a lower apparent K m value and a higher V max / K m ratio than free GOx, indicating enhanced apparent catalytic efficiency. In addition, GOx@MNPAES demonstrated good storage stability, rapid magnetic separation, and high reusability, retaining approximately 60% of its initial activity after 20 cycles. These results suggest that magnetic PAES‐COOH nanofibers are effective carriers for GOx immobilization.