Smart multifunctional hydrogels with shape memory, conductivity, self-healing, and adhesive properties for biomedical applications

Shape memory hydrogels often suffer from slow recovery, mechanical weakness, and poor stability under physiological environments, limiting their biomedical applicability. Herein, we developed a multifunctional smart hydrogel composed of gelatin, chitosan, alginate, and montmorillonite clay (GCAM), engineered for advanced biomedical applications. The hydrogel exhibited ion-responsive shape memory behavior, through Ca 2+ -mediated “egg-box” fixation and HCO 3 − -induced recovery, achieving robust recovery of complex geometries. GCAM hydrogels showed high swelling ratios (324.1 ± 22.4%), interconnected porous structure, excellent skin adhesiveness without residue, and controlled degradation (14.1 ± 0.3% weight loss by day 20 and 85.4 ± 2.1% by day 60 in PBS). The hydrogel exhibited rapid self-healing (≤1 h), recovering ∼90% tensile strength and maintaining electrical conductivity to enabling LED illumination in a closed circuit. Enoxaparin was successfully encapsulated and released in a sustained manner for up to 14 days, with cumulative release of 91.62 ± 5.42%. The hydrogel showed strong biocompatibility with over 80% HUVEC viability at 80 μg/mL, excellent hemocompatibility, and promoted vascularization in the CAM assay. Collectively, these findings highlight the multifunctional potential of the GCAM hydrogel for advanced biomedical and wearable applications