Aggregation-induced emission fluorogenic probes for wash-free imaging of lipid droplets in living cells

As essential subcellular organelles, lipid droplets (LDs) are involved in various the pathophysiological processes of metabolic diseases, including fatty liver and diabetes. Therefore, detecting LDs is conducive for studying the pathogeny and the early diagnosis of associated diseases. In this work, a series of fluorescent probes L1-L3 based on triphenylamine derivatives were designed and synthesized for tracking LDs in living cells. Due to the different terminal moieties of the three probes, L1 and L3 are aggregation-induced emission (AIE)-active, while L2 is a dual-state emission (DSE) molecule. In addition, confocal cell imaging experiments showed that probes L1-L3 specifically target intracellular LDs sites without the post washing. Importantly, probe L3 allows real-time monitoring of the dynamic processes and changes in the number of LDs. In summary, probe L3 is an ideal probe for studying LDs-related pathophysiological processes, and this work provides more ideas for the future design and synthesis of high-performance fluorescent probes for targeting LDs.