THERANOSTIC SYSTEMS BASED ON AIEGENS
Ben Zhong Tang
The Hong Kong University of Science & Technology, Hong Kong
Traditional π-conjugated fluorophors are prone to aggregate with light emission quenching which is known as aggregation-caused quenching (ACQ). We have observed an opposite phenomenon termed “aggregation-induced emission” (AIE) and identified the restriction of intramolecular rotation (RIR) as the main reason for the AIE effect. Guided by the RIR mechanism, we have developed a series of new AIE materials with emission colors covering the whole visible spectrum, fluorescence quantum yields up to unity. Nanoparticles of the AIE materials with efficient fluorescence and excellent biocompatibility can be readily fabricated. The nanoparticles of the AIE materials with specific surface functional groups exhibit high emission efficiency, large absorptivity, excellent biocompatibility and strong photo-stability, endowing them ideal for targeting specific cells and/ or tissues, and long-term non-invasive in vitro and in vivo cell tracing. Moreover, some AIE materials show aggregation enhanced photodynamic activity and the formulated AIE dots have been used for targeted and imaging-guided photodynamic cancer therapy.