AIEgen based drug delivery systems for cancer therapy.

Fluorescent drug delivery systems provide a means to track drug release, trace processes of translocation, monitor excretion of anticancer agents and predict therapeutic responses. Traditional fluorescent dye-labeled drug delivery systems often suffer from notorious aggregation-caused quenching (ACQ) with greatly impeded imaging performance. The emerging fluorogens with aggregation-induced emission characteristics (AIEgens) have provided an elegant alternative to tackle this challenge. Recently, fluorescent drug delivery systems based on AIEgens which combine fluorescence imaging and drug delivery have been extensively studied for the development of theranostic nanomedicine. In this review, we summarize the recent development of fluorescent drug delivery systems using AIEgens as the signal reporter. This review is organized according to the drug delivery systems, which include: (1) AIEgens as the drug delivery carrier; (2) AIE polymer as the drug delivery carrier; (3) Organic-inorganic AIE nanocarrier for drug delivery; (4) Supramolecular AIE system for drug delivery. Through illustration of their design principles and application examples, we hope to stimulate more interest in the design of more advanced fluorescent drug delivery systems based on AIEgens for cancer therapy.