Chitosan-based enzyme-immobilized nanocomposite cryogels with controlled biodegradation profile

Tissue engineering is a technique that applies temporary biomaterials as scaffolds to facilitate the regeneration of native tissue. A critical challenge is precisely controlling the degradation rate of these scaffolds to match the pace of new tissue formation, ensuring optimal integration and functional recovery. In this study, poly(glycerol carbonate methacrylate) (p(GCMA)) nanoparticles with an average diameter of ∼50 nm were successfully synthesized. These nanoparticles were incorporated into chitosan-based nanocomposite cryogels, which exhibited a macroporous structure with pore sizes of 55-60 μm and a swelling capacity 23 to 35 times of their dry weight. Incorporation of p(GCMA) significantly enhanced their flexibility and thermal stability of nanocomposite cryogels. Importantly, p(GCMA)-containing cryogels effectively immobilized up to 7 mg/g of protease within crosslinked network, allowing for sustained enzyme release and controlled biodegradation under physiological conditions. Notably, cryogels containing 50 mg/mL of p(GCMA), after enzyme immobilization under optimal conditions, exhibited approximately 17 % of moderate weight loss over 15 days, while pure chitosan cryogels without enzyme immobilization remained undegraded over the same period. Biocompatibility assessments with L929 fibroblast cells showed no significant cytotoxic effects, confirming material's suitability for biomedical applications. These findings underscore potential of enzyme-containing, chitosan-based nanocomposite cryogels as biodegradable materials with significant biomedical applications.