IMX Seminar Series - Engineering Granular Hydrogels for Biomedical Applications

Hydrogels represent a class of biomaterials that have great promise for the repair of tissues, particularly due to our ability to engineer their biophysical and biochemical properties.  Hydrogels can provide instructive signals through material properties alone (e.g., mechanics, degradation, structure) or through the delivery of therapeutics that can influence tissue morphogenesis and repair.  In recent years, we have transitioned from traditional hydrogels to granular hydrogels that are comprised of smaller hydrogel units (i.e., microgels). Microgels can be readily fabricated through microfluidics, with variations in microgel size, shape, and throughput based on device design. Granular hydrogels are formed through the packing of microgels and can be designed to be injectable through shear-thinning behavior, heterogeneous through microgel mixing, and porous to support cell invasion. I will give examples of the design and use of granular hydrogels based on hyaluronic acid for use as injectable therapeutics for endogenous tissue repair or in 3D printing to fabricate hydrogel constructs. For cardiac therapeutics, we injected heterogeneous granular hydrogels into the myocardium and showed selective microgel degradation to release factors and introduce porosity for cellular ingrowth. In 3D printing, we jammed microgels to form shear-thinning and self-healing hydrogels that could be printed either onto surfaces or within other hydrogels. These could be cell-laden or stabilized where necessary with secondary crosslinking. As a last example, we have fabricated granular hydrogels from hydrogel fibers that assemble into structures that permit cell encapsulation and cell-mediated compaction, mimicking features of extracellular matrix. Overall, the design of granular hydrogels opens up new opportunities in the design of functional hydrogels for biomedical applications.
Bio: Jason A. Burdick, PhD is the Robert D. Bent Professor of Bioengineering at the University of Pennsylvania. Dr. Burdick’s research involves the development of hydrogels through techniques such as photocrosslinking and self-assembly and their processing using approaches such as electrospinning and 3D printing.  The applications of his research range from controlling stem cell differentiation through material cues to fabricating scaffolding for regenerative medicine and tissue repair.  Jason currently has over 275 peer-reviewed publications, he is on the editorial boards of Journal of Biomedical Materials Research A, Biofabrication, Bioengineering, and Advanced Healthcare Materials, and he is an Associate Editor for ACS Biomaterials Science & Engineering. He has been recognized through numerous awards such as a Packard Fellowship in Science and Engineering, an American Heart Association Established Investigator Award, the Clemson Award for Basic Science through the Society for Biomaterials, and the Acta Biomaterialia Silver Medal Award. Jason has also been elected as a Fellow of the American Institute for Medical and Biological Engineering, to the International College of Fellows of Biomaterials Science and Engineering, and as a Fellow of the National Academy of Inventors. Lastly, he has founded several companies to translate technology developed in his laboratory towards clinical application.