Facile and green fabrication of biomimetic gelatin-siloxane hybrid hydrogel with highly elastic properties for biomedical applications

Non-covalent hydrogel attracted a great deal of interest in drugs delivery and tissue regeneration areas because of its excellent characters such as mild preparation conditions and easily controlled structure and properties. Herein, we conducted a study on fabricating a biomimetic gelatin-siloxane (GT-S) hybrid hydrogel with tunable composition and properties by a facile and green method. The hybrid hydrogel was formed in biocompatible phosphate buffer solution (PBS) by a simple physical cross-linking mechanism. Hydrogels' composition, chemical structure, mechanical properties, biodegradation and cellular biocompatibility were investigated in various conditions. The results showed that siloxane contents and curing temperatures had important effects on hybrid hydrogel structure and properties. GT-S hydrogel with optimized siloxane content and curing temperature exhibited high compressive elasticity (3.6 MPa at 86% strain, 85 wt% water) and excellent controlled biodegradation behavior with PBS and enzyme. Furthermore, GT-S hydrogel was shown to support marrow stem cell attachment and proliferation. This study conclusively demonstrates that our hybrid hydrogel has special properties including high elasticity and controlled biodegradation in various conditions. Therefore, it may act as a promising candidate in special biomedical applications such as implants for drugs delivery and scaffolds for tissue regeneration.