Collagen immunostaining (green) of rabbit’s colon (red), and Dendrimer:Dextran adhesive hydrogel (green) applied to rat’s colon (red).
Biomaterials of ever-greater sophistication are being implanted in the body for the purposes of drug delivery, tissue regeneration, and structural support. An ongoing challenge, however, has been appropriately designing biomaterials in vitro that will exhibit optimal in vivo performance. The complex chemical, mechanical, and biological environment inside the body is highly variable based on the site of implantation, disease states, and the dynamic cellular milieu following implantation. This complexity makes traditional static and inert materials unlikely candidates for successful implants. To address this shortfall, we design ‘smart’ injectable biomaterial systems that dynamically interact with the implantation site in a tissue- and disease-specific manner. We use polymer chemistry, mechanical testing, in vivo tracking of tagged polymers and drugs, and a variety of disease models to develop rationally designed biomaterials with controlled tissue integration, drug release kinetics, mechanics, and degradation profiles. By using modeling to correlate in vitro data with in vivo performance, we can dramatically accelerate the development of new biomaterial ‘platforms’ that can be tuned for different disease states and implantation sites.