Influence of network parameters on the properties of dynamic, protein-based hydrogels

PMSE 142

Zhijie Sui, zsui@wisc.edu1, William J. King, wjking@wisc.edu1, and William L. Murphy, wlmurphy@wisc.edu2. (1) Department of Biomedical Engineering, University of Wisconsin, 2145 Engineering Centers Building, 1550 Engineering Dr, Madison, WI 53706, (2) Department of Pharmacology, University of Wisconsin, 1550 Engineering Drive, Madison, WI 53706
Dynamic hydrogels have become an important tool in multiple disciplines due to their ability to sense environmental changes and respond with structural changes. In a previous study, we reported a novel dynamic hydrogel that is capable of translating a molecular-level protein conformational change to a macroscopic volume change in response to ligand-protein binding. Specifically, our general approach involves photo-crosslinking of networks composed of two components: 1) the dynamic protein calmodulin (CaM); and 2) acrylate-terminated poly(ethylene glycol) chains. Crosslinking of these molecules results in formation of a hydrogel network that undergoes pronounced macroscopic structural changes upon binding of the small molecule ligand trifluoperazine to CaM. Here we report a systematic study of the influence of network parameters (e.g. polymer molecular weight, chain concentration) on the dynamic properties of calmodulin-based hydrogels. This study provides a preliminary understanding of physics of protein-based hydrogel networks, and examines the associated dynamic properties of these materials.