Designing Self-Healing Hydrogels with Antibacterial Property Based on Host–Guest Interactions between Aminoazobenzene-Modified Gelatin and Polycyclodextrin for Prolonging the Shelf Life of Tyrosinase Enzyme
Shaghayegh Vakili, Hamed Azadfar, Ebrahim Ahmadi, Zahra Mohamadnia, Atiyeh Mahdavi, Faezeh Hanifeh
Abstract
Here, a self-healing hydrogel was designed and synthesized to immobilize tyrosinase enzyme (Tyr), addressing the need for improved enzyme performance. The self-healing properties of the hydrogel ensured structural integrity, while its enzyme immobilization capability significantly enhanced enzyme stability and activity. The hydrogel was synthesized via host–guest interactions between polycyclodextrin (PCD) and aminoazobenzene-modified gelatin (Gel-AZO), and chemically cross-linked in the presence of glycidyl methacrylate-modified gelatin (GM-Gelatin) and acryloyloxyethyltrimethylammonium chloride (DAC) to form a dual-network structure. The immobilized enzyme retained 94.56% of the free enzyme’s activity and remained stable under varying pH and temperatures, maintaining 70% activity at 70 °C. Reusability tests showed preserved enzymatic activity over six cycles. The hydrogel exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli, maintained cell viability above 80%, and showed hemolytic activity below 5%. These results highlight the potential applicability of this self-healing hydrogel in biomedical and industrial settings that require stable enzymatic performance.