A responsive hydrogel-based material may be used as a carrier system for the in situ delivery of various cargo substances, including bioactive moieties. The hydrogel structure, which includes photodegradable and thioether moieties in its three dimensional network, enables finely tuned local release of cargo substances as a function of the in vivo tissue environment (e.g., enzyme concentration or reducing environment) and externally applied stimuli (e.g., light) by selective spatiotemporal hydrogel degradation.