UV Cross-Linked Dextran Methacrylate—Concanavalin A Methacrylamide Gel Materials for Self-Regulated Insulin Delivery

Abstract

In this study, the successful acrylic derivatization of dextran and concanavalin A (con A) to form dextran methacrylate and con A methacrylamide is shown. These derivatized acrylic monomers are then photopolymerized in the presence of a water soluble photoinitiator Irgacure® under various conditions to form covalently bonded glucose-responsive gel materials, which undergo a transformation to sol in the presence of free glucose. Rheological data have revealed that as the degree of substitution for dextran methacrylate is increased, a more elastic material is produced due to the increased covalent linkages. Some of these gel systems show negligible component loss in in vitro diffusion experiments used to simulate the behavior of the cross-linked gel, as would be used in a self-regulated insulin delivery device.

Keywords:

• dextran methacrylate
• concanavalin A
• closed loop
• insulin delivery
• UV-polymerization
• rheology