UC Berkeley

Hydrogels have been used to develop scaffolds to address challenges in tissue engineering and drug delivery for several decades. The major advantage of using hydrogels is that their high water content and low stiffness enables them to mimic tissue-like environments. In my work, I develop four unique hydrogels using a single polymer, elastin-like polypeptide. The first challenge I address is that of hydrogel extensibility. Typical hydrogels cannot undergo large strains, which limits their durability and applicability to active tissues such as muscles. I use ELP to create a rubber-like elastic hydrogel that can stretch to 15 times its original length. Unlike most previous ELP hydrogels, our gels can reach such high strains due to the well-defined structure of our materials with minimal crosslinks. Next, I focus on developing an adhesive hydrogel using ELP. Unlike most adhesives, especially protein-based adhesives, our adhesive hydrogels are flexible and deswell in physiological conditions. This improves their potential for success in practical applications. We also developed a self-healing hydrogel by combining ELP with bioglass. Unlike other strategies that use reversible physical bonds, we use pH driven reversible Schiff base formation to synthesize hydrogels. Bioglass raises the localized pH to yield ideal conditions that favor gelling in our system. We also show that our materials can self-heal after being severed, which makes them durable and ideal for topical applications. Finally, we employ our efforts in the design and synthesis of protein-based beads for biolaser development. These devices are stimuli-responsive, which makes them ideal for optical sensing applications for biomolecule sensing and the flexibility of the hydrogels also makes them suitable for studying cellular biophysics. Through my dissertation, I hope to convey the versatility of ELP and the potential of structural design that can lead to the development of hydrogels with diverse functions.