FURI | Spring 2022

Characterization of Adhesive Peptide Binding Efficacy in SPAAC and Michael-Type Addition PEG Hydrogels to Support Encapsulated Pancreatic Islet Cell Viability

A promising treatment for Type 1 diabetes is encapsulation of pancreatic islet cells in hydrogels, which may prevent transplant issues, like immune rejection. These hydrogels can be modified to promote passive nutrient diffusion and prevent hypoxia via injection molding that produces geometries with reduced diameters. Polyethyleneglycol-maleimide (PEG-MAL) is a common macromer used to encapsulate islet cells, but gels too quickly for injection molding. Consequently, this research focuses on slower gelling alternative, strain-promoted azide-alkyne cycloaddition (SPAAC) hydrogels. This research characterizes SPAAC hydrogel suitability for cell encapsulation by comparing binding efficacy of Azide-functionalized adhesive peptide, RGD, versus thiol-functionalized RGD binding to PEG-MAL.