A BODIPY-based fluorescent chemosensor with 2, 6-substitution for visual and highly selective detection of S2-

BODIPY derivatives have often been employed as fluorescent sensors to probe toxic ions in environment and living systems, such as sulfide ion (S2-). Whilst many structure modifications have been exploited on groups at the 3, 5, 8-positions, there are quite few examples on tailoring the 2,6-substituents for chemosensor investigations. Herein, we design and synthesize a 2,6-substituted BODIPY molecule, LM-BDP, to use as a fluorescent probe for detecting S2- in aqueous media. The electronic and crystal structures of the probe are studied by density functional theory (DFT) calculations and single-crystal X-ray diffraction analysis. Spectroscopy investigations are performed in a variety of conditions, showing that LM-BDP exhibits a noticeable color change from pink to dark red and a fluorescence shift from yellow to pink channel with decreased intensity upon addition of S2-. The selectivity and sensitivity measurements show that LM-BDP can only response to S2- with a detection limit of 0.29 & mu;M in less than 100 s. The remarkable contrast in fluorescence images in test-stripe and RAW 264.7 cell experiments indicates that the probe is a proper candidate for the application in detecting exogenous S2-.

Automated summary

This study designs and synthesizes a 2,6-substituted BODIPY molecule, LM-BDP, as a fluorescent probe for detecting S2- in aqueous media. The electronic and crystal structures of the probe are studied using density functional theory (DFT) calculations and single-crystal X-ray diffraction analysis. Spectroscopy investigations show that LM-BDP exhibits a noticeable color change from pink to dark red and a fluorescence shift from yellow to pink channel with decreased intensity upon addition of S2-. The probe shows high selectivity and sensitivity with a detection limit of 0.29μM in less than 100 s, and it demonstrates significant fluorescence contrast in test-stripe and RAW 264.7 cell experiments, making it a suitable candidate for detecting exogenous S2-.