Multi-Stimuli-Responsive Hydrogels: From Strategic Design to Biomedical Applications

Multi-stimuli-responsive hydrogels have emerged as versatile biomaterial platforms for biomedical applications owing to their capacity to recognize and respond to multiple environmental signals. Such integration can provide responsiveness to signals that vary spatially and temporally. However, the effectiveness of such integrated systems requires more than simply incorporating signal-recognition components: the response characteristics of individual components must be preserved after integration and translated into measurable network-level changes rather than inferred from component-level sensitivity alone. This review develops a structure-response-application framework for multi-stimuli-responsive biomedical hydrogels. Strategies based on responsive polymer segments, dynamic covalent bonds, and functional nanocomposites are examined according to how responsive components are structurally integrated and coordinated to achieve application-specific functions. By connecting component integration with biomedical function, this cross-scale framework provides criteria for selecting integration strategies and assessing whether multiple responses are functionally coordinated rather than merely coincident.