Tumor tissues diagnosis with PIEE lipid droplet vesicles

Abstract

A molecule ANB (6-(4-aminostyryl)-1,3-dioxo-1H-benzo[de]isoquinolin -2(3 H)-yl)-n-butane), was developed for fluorescence turn-on imaging of cancer cells lipid droplets (LDs). ANB exercised synergistically aggregation induced emission enhancement and photochromism, which are essential to construct a photoinduced emission enhancement (PIEE) LDs. The fluorescent nanostructures PIEE-LDs extremely improve intracellular imaging contrast with high emission intensity, high emission contrast to cytosol and high photostability. Following these unique optical properties, we statistically analyzed the differences of LDs between cancer and normal cells as well as successfully observed LDs progression and fusion in living cells over a long period. Consequently, the xenograft tumor tissues were favorably distinguished from normal based on this superior PIEE-LDs. It is known that ANB exhibited excited-state conformational conversion between the twist intramolecular charge transfer (TICT) and local excited (LE) states. Based on the results of our studies, we found that LE state became dominate and presented aggregation induced emission enhancement when ANB stay in LDs, which allows us to build a fluorescent nanovesicle model to explain the distinct fluorescence imaging of ANB in LDs. Furthermore, photochromism occurred when irradiation that could promoted emission behavior of bright nanovesicles LDs to further level, and achieve PIEE-LDs.