A highly selective ratiometric fluorescent probe based on naphthalimide for detection and imaging of CYP1A1 in living cell and Zebrafish

Real-time monitoring Cytochrome P450 1A1 (CYP1A1) activity in complex biological systems via a practical tool is highly sought after because of its significant role in various xenobiotics metabolism and bioactivation. Herein, according to slight differences in 3D structure and substrate preference between CYP1A1 and its homologous CYP1A2, a series of novel ratiometric fluorescent probes were designed and synthesized using 1, 8-naphthalimide because of its good water solubility and the trait of naked-eye visiblization and ratiometric fluorescence to achieve detection of CYP1A1 in biological samples. Among these probes, N-((2-hydroxyl ethoxy)ethyl)-4-isopropoxy-1,8-naphthalimide (NEiPN) displayed highly isoform selectivity and great sensitivity for CYP1A1 under simulated physiological condition. Remarkably, probe NEiPN exhibited excellent reproducibility when it was used to detect the CYP1A1 content in human liver microsomes, which meant it had a great potential for quantifying the contents of CYP1A1 in real biological sample. Futhermore, NEiPN showed relatively low cytotoxicity and had been successfully applied in biological imaging in living cell and zebrafish. These findings indicate that NEiPN is capable of real-time monitoring the activity of endogenous CYP1A1, which could provide support for CYP1A1-associated pathological processes.