Alterations of cellular redox status are closely associated with physiological and pathological processes.Glutathione (GSH) and H 2 O 2 should be the most representative redox couple in living cells. However, up to now, there is no way to reversibly detect GSH/H 2 O 2 . In this report, a near-infrared (NIR) fluorescent probe (Cy-O-Eb) for monitoring the changes of GSH/H 2 O 2 levels in vivo was developed based on switching on-off a five-membered ring involved in ebselen. This probe could reversibly respond to GSH and H 2 O 2 with high selectivity, sensitivity and mitochondrial targeting. It was successfully used to monitor the changes of redox status during apoptosis and the H 2 O 2 changes at the wound margin in zebrafish larvae. Thus, the probe would provide an ideal tool for monitoring redox status changes and studying molecular events involved in redox regulation.

In this study, we have designed and synthesized a new near-infrared (NIR) fluorescent probe (BODIPY-Se) to detect fluorine ions (F  ) using a B-Se bond to connect the fluorescent dye BODIPY and benzotrifluoride. The probe exhibited a highly selective fluorescence response to F  with a detection limit of 7.4 × 10 8 mol/L. The excitation and emission spectra of the probe in the NIR region avoid background fluorescence interference present in biological systems. The fluorescent imaging of HepG2 cells demonstrated that the newly developed probe should be broadly applicable to detect F  in living cells.