Chitosan–Silk Fibroin Hydrogel Scaffold Incorporating Bioactive Aloe vera and Mimosa Complex for Cartilage-Supportive Applications

A composite hydrogel scaffold comprising chitosan, silk fibroin, Aloe vera extract, and Mimosa complex was fabricated and thoroughly characterized. Upon freeze-drying, the scaffolds displayed a uniform cylindrical geometry with a highly porous, interconnected polymeric network. Quantitative image analysis revealed a mean pore diameter of 43.09 ± 2.27 µm alongside an overall porosity of 61.4 ± 6.2%. ATR-FTIR and XRD analyses confirmed successful inclusion of the complex formation and the incorporation of all constituents into the final formulation. The scaffold exhibited a compressive modulus of 46.63 ± 22.71 kPa (dry) and 5.40 ± 3.73 kPa (hydrated), with a swelling ratio of 756.62 ± 114.08%, supporting its suitability for physiological applications. TGF-β3 loading via adsorption yielded an entrapment efficiency of approximately 79.18%, reflecting effective physical immobilization throughout the polymer matrix. Cytocompatibility was subsequently assessed using an indirect contact model combined with an MTT assay, both of which confirmed that TGF-β3-loaded scaffolds exerted no cytotoxic effects on chondrocytes. After 28 days in culture, scanning electron microscopy revealed pronounced cell adhesion, preservation of rounded cell morphology, and ECM deposition along pore walls and throughout interconnected channels. Immunofluorescence analysis further demonstrated a time-dependent accumulation of aggrecan and collagen type II within the three-dimensional scaffold architecture. Collectively, these findings suggest that the developed composite hydrogel scaffold is well-suited for cartilage-related in vitro culture applications.