Domain Morphology and Rheological Properties of Protein-Polyelectrolyte Complex Hydrogels

Polyelectrolyte complex (PEC) hydrogels are physically-crosslinked three-dimensional (3D) polymeric networks that electrostatically self-assemble from two oppositely-charged ABA polyelectrolytes. The associative microphase separation of the A-blocks (limited by the B-blocks) results in polymer dense domains within a 3D network that are responsible for the unique physical and mechanical properties of PEC hydrogels, such as their ability to encapsulate charged macromolecules. Previous research has demonstrated a relationship between PEC domain morphology and the mechanical properties of PEC hydrogels, but data on how protein additives affect that relationship is still unknown. In this poster, we use small-angle X-ray scattering to determine the domain morphology of protein-PEC hydrogels and use rheology to uncover how protein additives affect the shear properties of PEC hydrogels. This work establishes basic design criteria for moduli-tunable, biomedically relevant protein-PEC hydrogels.