Biocompatible and Photostable AIE Dots with Red Emission for In Vivo Two-Photon Bioimaging

Bioimaging systems with cytocompatibility, photostability, red fluorescence, and optical nonlinearity are in great demand. Herein we report such a bioimaging system. Integration of tetraphenylethene (T), triphenylamine (T), and fumaronitrile (F) units yielded adduct TTF with aggregation-induced emission (AIE). Nanodots of the AIE fluorogen with efficient red emission were fabricated by encapsulating TTF with phospholipid. The AIE dots enabled three-dimensional dynamic imaging with high resolution in blood vessels of mouse brain under two-photon excitation.