Fabrication of highly stretchable hydrogel based on crosslinking between alendronates functionalized poly-γ-glutamate and calcium cations

We report a highly stretchable hydrogel based on the crosslinking structure between calcium cations and alendronates (ALN) conjugated with poly-γ-glutamate (γ-PGA), a typical biodegradable polymer. γ-PGA with ALN (γ-PGA-ALN) forms the hydrogel in the aqueous solution containing CaCl2. The hydrogel shows 2000% of stretchability and reversible stretching without failure at a strain of 250%. The fracture strain and stress are tunable by varying the concentration of either γ-PGA-ALN or CaCl2, indicating the importance of fine-tuning of the density of the cross-linkage to control the mechanical properties of the hydrogel. We believe the biodegradable polymer based highly stretchable hydrogel has potential for use in various fields such as tissue engineering. We demonstrate the design of a highly stretchable hydrogel based on the crosslinking structure between calcium cations and alendronates (ALN) conjugated with poly-γ-glutamate (γ-PGA), a typical biodegradable polymer. γ-PGA-ALN forms the hydrogel in calcium ion aqueous solution and the hydrogel shows 2000% of stretchability and reversible stretching without failure at a strain of 250%. [Display omitted]