Real-time tracking of endogenous CYP2J2 by red-emitting aggregation-induced emission probe with large Stokes shift

The abnormal expression of cytochrome P450 2J2 (CYP2J2) is closely related to the proliferation of human cancer cells. In this study, a red-emitting probe with an aggregation-induced emission (AIE) effect for the quantification of CYP2J2 was developed by modifying the typical AIE fluorescent group tetraphenylethylene (TPE) through two-step synthesis. Upon addition of CYP2J2, the probe underwent O-demethylation and spontaneously 1,6-elimination reactions of p-hydroxybenzyl that allowed it to alter its photophysical properties, thus realizing light-up detection of CYP2J2 with extremely large Stokes shift (236 nm), excellent sensitivity and selectivity, low detection limit (1.09 nM). Moreover, this new AIE-active probe with good biocompatibility was admirably employed to tracking endogenous CYP2J2 in living cells. •An AIE-based fluorescent probe (TPE-Bn) was designed to detect CYP2J2.•This probe showed significant Stokes shift (236 nm), good photostability, excellent sensitivity and selectivity, and low cytotoxicity.•This probe can be used to visualize endogenous CYP2J2 in living cells and tissues.