(395b) Tailoring the Mechanical Properties of Multi-Functional Polyampholyte Hydrogels for Tissue Engineering Applications

The development of novel polymeric scaffolds for tissue engineering depends on the successful demonstration of three critical features: resistance to nonspecific protein adsorption, the capability to deliver bioactive signaling molecules over both short and long term timelines, and the ability to easily tune the mechanical properties to match the tissue of interest. While there are numerous polymeric platforms that can address these three features individually, there are few, if any platforms that can adequately meet all three. Our work is focused on demonstrating the capability of polyampholyte polymers composed of equimolar concentrations of positively and negatively charged subunits to meet all three criteria. Polyampholyte hydrogels composed of varying ratios of [2-(acryloyloxy)ethyl] trimethylammonium chloride (TMA, positively charged), 2-carboxyethyl acrylate (CAA, negatively charged), and 3-sulfopropyl methacrylate (SA, negatively charged) monomers were synthesized. Regardless of the underlying composition, the hydrogels were demonstrated to be resistant to nonspecific protein adsorption from both negatively charged fibrinogen and positively charged lysozyme. All of the different hydrogel compositions were also demonstrated to be capable of covalently attached bioactive molecules using EDC/NHS conjugation chemistry. Finally, the mechanical properties of the resulting hydrogels were demonstrated to be dependent upon the composition, allowing for tunability in this property. When these results are coupled to the literature regarding polyampholyte polymers, it can be concluded that these systems represent a promising approach for tissue engineering applications.