Hemocompatible polymeric hydrogels with tunable photoresponsive volumetric properties

Hydrogels exhibit crosslink density-dependent properties that can be tuned to achieve spatiotemporal control, making them well-suited for a wide range of biomedical applications. In particular, light reactive hydrogels have requisite features for use in size-changing biomaterial devices such as pediatric blood shunts, that can uniquely meet evolving patient-specific needs after in vivo implantation. Here, we report on the design of a tunable photoresponsive and hemocompatible methacrylated dextran hydrogel suitable for use in such devices. The formation and subsequent deswelling of hydrogels proceeded through discrete sequential photopolymerization steps. The range of geometric tunability (up to 20% volume change) was a function of methacrylate density (e.g., polymer modification and concentration) and the extent of initial polymerization that was controlled via exposure time, intensity, and photoinitiator concentration. Furthermore, the hydrogels exhibited long-term (>3 months) stability and hemocompatibility, including with blood-borne cell types (e.g., erythrocytes and leukocytes). In vitro verification demonstrated the feasibility of this concept; our elucidation of the parameter space governing hydrogel properties will facilitate the use of the platform in various blood-interface constructs, specifically pediatric blood shunts.