Michael addition crosslinking

Michael-type addition in the context of tissue engineering refers to the addition of a nucleophile (typically a deprotonated thiol) onto a double bond conjugated to an electron withdrawing group such as a carbonyl (typically vinyl sulfone, maleimide, or acrylate). It is also known as conjugate addition or 1,4-nucleophilic addition.

Figure 1. Polymers are linked by Michael-addition crosslinking. The link between thiols and vinyl sulfone are shown in red.

Michael addition between thiols and acrylates or vinyl sulfones can occur in an aqueous medium, at room temperature, and at physiological pH.