A near-infrared HBT-based fluorescent probe for tracking carbon monoxide-releasing CORM-3

Tricarbonylchloro(glycinato)ruthenium (CORM-3) has important application in the treatment of clinical diseases because of anti-inflammatory and heart-protecting properties, and is also used to study the metabolic mechanism of endogenous carbon monoxide as a safe and convenient carbon monoxide-releasing agent in vivo due to good water solubility and releasing controlled amounts of CO. Thus the development of effective detection methods to achieve the analysis of CORM-3 is of great significance in monitoring CORM-3 and studying the specific mechanism of endogenous CO in biological samples. Herein a small molecule fluorescent probe was developed by selecting 2-(2-hydroxyphenyl)benzothiazole (HBT) derivative as the optical signal unit and 4-nitrobenzyl moiety as the reactive unit. It could quickly detect CORM-3 within 15 min by the enhanced near-infrared fluorescence at 720 nm without the participation of heavy metal ions, accompanied by the large Stokes movement of 195 nm. The detection limit and linear range of the probe toward CORM-3 were achieved 0.11 mu M and 0 - 175 mu M, respectively. Besides, this probe displayed a red-edge effect, and the excitation wavelength and emission wavelength may be adjusted reasonably according to the test requirement to avoid interference signal. More importantly, it has been successfully used for the detection of CORM-3 with high resolution of fluorescence imaging in living cells and Zebrafish.