(549a) Development of Biodegradable Hydrogel Composites for Growth Plate Regeneration

The growth plate, or physis, is the site of new bone formation near the end of bones in children resulting in longitudinal and circumferential growth. Injury to this area can significantly effect normal growth and development. In many cases, an injury can result in formation of a bone bridge that can lead to growth arrest, which could eventually create angled growth and deformity. The goal of this research is to develop a hydrogel construct that displays the mechanical properties inherent to the natural growth plate, as well as a degradation profile that would allow new tissue to form, allowing continued growth. Here, a porous hydrogel scaffold has been created by suspending fast-degrading hydrogel particles into a longer degrading outer matrix. This system allows for the controlled opening of pores during the degradation, as well as potential for multiphase drug release. The degradation was characterized by gravimetric analysis of samples immersed in PBS at 37°C. SEM imaging was used to characterize the porousity of the systems. The potential for multiphase drug release was demonstrated by measuring the amount of fluorescently labeled lysozyme released during degradation. Finally, cellular toxicity and attachment data were obtained by exposure of the final degradation products and the hydrogel scaffolds to D1 pluripotent mesenchymal cells.