In human body, carboxylesterases (CEs) play the crucial roles in xenobiotic metabolism and lipid homeostasis. But the abnormal CEs expression is highly associated with some diseases, such as hyperlipidemia, diabetes and liver cancer. Therefore, it is of great significance to develop an efficient tool for the accurate detection of CEs in living organisms. Herein, an innovative near-infrared (NIR) fluorescent probe TTAP−AB has been designed for CEs detection based on aggregation-induced emission (AIE) mechanism. This probe exhibits rapid response (2 min), excellent sensitivity (limit of detection = 8.14×10−6 U/mL), and high selectivity towards CEs. Additionally, owing to the good biocompatibility, probe TTAP−AB enables to monitor the dynamic changes of CEs level under drug-induced modulation in living cells and zebrafish. More importantly, probe TTAP−AB is successfully employed to image the liver tumor and assist tumor resection by the real-time monitoring of CEs, indicating that TTAP−AB is promising to guide liver cancer surgery. Therefore, probe TTAP−AB can not only enrich the strategies for CEs detection in biological systems, but also has great potential for some clinical imaging applications, including medical diagnosis, preclinical research, and imaging-guided surgery.

Hypochlorite (ClO−) and viscosity both affect the physiological state of mitochondria, and their abnormal levels are closely related to many common diseases. Therefore, it is of great significance to develop a mitochondria-targeting fluorescent probes for the dual sensing of ClO− and viscosity. Herein, we have explored a new fluorescent probe XTAP−Bn, which responds sensitively to ClO− and viscosity with off-on fluorescence changes at 558 and 765 nm, respectively. Because the emission wavelength gap is more than 200 nm, XTAP−Bn can effectively eliminate the signal crosstalk during the simultaneous detection of ClO− and viscosity. In addition, XTAP−Bn exhibits a series of advantages, including high selectivity, rapid response, good water solubility, low cytotoxicity, and excellent mitochondrial targeting ability. More importantly, probe XTAP−Bn has been successfully employed to monitor the dynamic change of ClO− and viscosity levels in mitochondria of living cells and zebrafish. Taken together, this work not only provides a reliable tool for identifying mitochondrial dysfunction, but also offers a potential approach for the early diagnosis of mitochondrial-related diseases.