Glycerol-modified γ-PGA and gellan composite hydrogel materials with tunable physicochemical and thermal properties for soft tissue engineering application

Biocompatible hydrogel materials are considered to be a crucial and indispensable character that transitorily supplants the natural skeleton and acts as a preferable microenvironment. In this study, two modifiers – poly(γ-glutamic acid) (γ-PGA) and glycerol (Gly) – were incorporated to form a rigid and coarse structure, which significantly ameliorates the mechanical and biological properties as compared with original gellan gum (GG). The surface characterization and thermal and mechanical properties of the modified compositions were scrutinized using SEM, FTIR, TGA, DSC, and tensile testing. The cytocompatibility and cell viability were reported by regulating fibroblast cells (L929). As a result, it is found that adequate γ-PGA modification considerably enhances the thermal and mechanical properties. The glycerol additives advance the elongation by decreasing the elastic modulus, and the modification did not cause a pernicious effect on chemical structure and non-toxicity according to a cellular response. The adhered fibroblast cells on suitable γ-PGA (0.5–0.7 w/v%) and glycerol (0–2 w/v%) modified structures present better proliferation and higher adhesion than those of pure GG and other study groups. These useful combinations inspired the prospective development of biodegradable hydrogel materials, which were enhanced with excellent material stability and biological activity, for utilization in soft tissue engineering.