Immobilization of α-amylase on electrospun polycaprolactone (PCL)/chitosan (CHI) nanofibers: a novel approach to improve enzyme stability and performance

Abstract

Enhancing enzyme resistance to environmental conditions and optimizing their catalytic performance are crucial for various industrial applications. Enzyme immobilization has emerged as one of the most effective strategies to achieve these goals. In this study, polycaprolactone/chitosan (PCL/CHI) nanofibers were successfully synthesized via electrospinning, followed by the covalent immobilization of α-amylase. The immobilization efficiency was determined, and the resulting nanofibers were characterized through FT-IR, SEM, EDX, and XRD. Optimal pH and temperature conditions for the immobilized enzyme were found to be pH and 50 °C, respectively. The activation energy (Ea) calculated using the Arrhenius equation was 5.14 KJ/mol, while the kinetic parameters K_m and Vmax were determined as 0.37 ± 0.11 mg/mL and 6.23 ± 0.87 µmol/min, respectively. Thermal stability tests revealed that at 50 °C, the immobilized enzyme retained over 50% of its initial activity. Additionally, the immobilized enzyme exhibited enhanced resistance to environmental stressors, including metal ions and organic solvents, compared to its free counterpart. The results confirm that the immobilization process not only improves enzyme stability but also boosts catalytic efficiency under specific conditions. This study provides a cost-effective, scalable, and practical approach for enzyme immobilization using electrospinning, with significant potential for industrial applications.