Enzymatic crosslinking

Endogenous or exogenous enzymes can mediate the crosslinking which allows in situ gelations in a biologic environment. These crosslinks have limited toxicity concerns because of the enzyme specificity.

Figure 1. Enzymatic crosslinked multi-armed polymer. Polymers are shown in grey.The links are created between lysine and glutamine by transglutaminase enzyme.

The most commonly used peroxides in hydrogels formation are transglutaminases (including Factor XIIIa) and horseradish peroxide (HRP).