Recent advances in stimuli-responsive theranostic systems with aggregation-induced emission characteristics

Theranostic systems by integrating the tumor imaging and tumor therapeutic capabilities into one platform have attracted numerous attentions from worldwide researchers. Despite the great developments, their clinical application is still in the nascent stage, owing to the unsatisfied imaging quality and limited therapeutic efficacy. Fortunately, the emerging of aggregation-induced emission (AIE) molecules with unique fluorescence property offers an opportunity to solve the imaging problem. Besides, further utilizing the tumor microenvironments and external triggers to design the stimuli-responsive imaging-guided therapy could enhance the therapeutic efficacy and reduce the side effects. In this review, the advancements in stimuli-responsive theranostic systems with AIE characteristics are summarized. Theranostic systems are first classified according to their treatment modes, and then subdivided based on various stimuli, including pH, redox, enzyme, and light. In each section, the design strategies and application examples are introduced. At last, the current state of the art, limitations, as well as prospects are also discussed.