Regulation of physicochemical properties of alginate-based hydrogels and preliminary applications in wound healing

Alginate (Alg) hydrogels have demonstrated great potential in drug delivery, wound dressings, and tissue engineering. However, the practical applications of conventional Alg hydrogels suffer from rapid degradation, insufficient controlled drug release, and poor adhesion to tissues. In this paper, the physicochemical properties of Alg hydrogels were comprehensively modulated through chemical modification and the incorporation of various polymers. The results showed that introducing neutral polymers stabilized Alg hydrogels at room temperature. However, this stabilizing effect did not persist at 37 °C. The cationic chitosan (CS) can bind to Alg through electrostatic interaction. The incorporation of CS substantially improved the stability of Alg hydrogels and remarkably prolonged the release of BSA from hydrogels to 14 days at 37 °C. Meanwhile, introducing dopamine (DA)-modified Alg enhanced the adhesion of hydrogel to porcine skin. The optimized hydrogels were utilized to encapsulate platelet-rich plasma (PRP). The PRP-loaded composite hydrogel (2 wt% Alg, with a Ca2+/carboxyl group molar ratio of 0.2, a DA/carboxyl group molar ratio of 0.2, and a CS content of 30 % of Alg) exhibited an excellent therapeutic effect in the healing of rabbit shoulder cuff injury. These findings provide valuable insights into the modulation of physicochemical properties of hydrogels for biomedical applications. Schematic illustration of physicochemical properties modulation of Alg hydrogels. [Display omitted] •The viscoelastic property of alginate hydrogels was effectively regulated.•The stability of alginate hydrogels was substantially improved in PBS at 37 °C.•Sustained protein release was achieved on alginate hydrogels.•Optimized alginate hydrogels containing PRP showed great therapeutic potential in the healing of rabbit rotator cuff injury.