A hydrogel composition is formed from a natural polymer derivative having a plurality of cross-linkable units depending therefrom, and a synthetic polymer derivative having a plurality of cross-linkable units depending therefrom, said natural and synthetic polymer derivatives having hydrolysable units disposed between the polymer backbone of said derivative and at least some of said cross-linkable units. The use of a combination of natural and synthetic polymers provides for biodegradability of the hydrogel, along with mechanical properties such as strength and elasticity.
