A fluorescent probe for monitoring carboxylesterases in pulmonary cells under permissive hypercapnia condition.

Herein, by combining the benzofuranone-derived fluorophore and the carbamate recognition group, a fluorescent probe named BFO-CarE was developed for monitoring the carboxylesterase (CarE) level in pulmonary cells under the permissive hypercapnia condition. It showed a notable fluorescence response towards CarE at 570 nm under the excitation of 510 nm. The in-solution tests revealed the advantages of BFO-CarE including high sensitivity, high specificity, relatively rapid response, and high steadiness. It was also low-toxic upon the pulmonary cell lines. During the intracellular imaging in pulmonary cells, BFO-CarE achieved the monitoring of the CarE level in both inhibition and activation status. In particular, BFO-CarE realized the visualization of the affection of the permissive hypercapnia condition on the CarE level, which indicated the hypoxia tolerance of CarE. This work was informative for investigating the impact of hypoxia in pulmonary cells, and the corresponding anaesthesia-related approaches.