Spatiotemporally Controlled Photoresponsive Hydrogels: Design and Predictive Modeling from Processing through Application

Photoresponsive hydrogels (PRHs) are soft materials whose mechanical and chemical properties can be tuned spatially and temporally with relative ease. Both photo‐crosslinkable and photodegradable hydrogels find utility in a range of biomedical applications that require tissue‐like properties or programmable responses. Progress in engineering with PRHs is facilitated by the development of theoretical tools that enable optimization of their photochemistry, polymer matrices, nanofillers, and architecture. This review brings together models and design principles that enable key applications of PRHs in tissue engineering, drug delivery, and soft robotics, and highlights ongoing challenges in both modeling and application. Photoresponsive hydrogels (PRHs) are an emerging class of soft materials whose mechanical properties can be programmed to evolve spatiotemporally with illumination. Their hydrophilic polymer networks crosslink or degrade as photosensitive components become activated. This review focuses on models and design principles enabling PRH applications in mechanobiology, drug delivery, and soft robotics, and highlights ongoing challenges in both modeling and application.