A 2, 7-naphthyridine-based fluorescent turn-on probe for detection of biothiols in vitro and in vivo

A 2,7-naphthyridine derivative (AND-OH) was used as a fluorophore in the development of a novel fluorescent turn-on probe (AND-DNBS) by introducing a 2,4-dinitrobenzenesulfonate functionality. This fluorescent probe was successfully used for sensing glutathione (GSH) in aqueous media and showed favorable properties such as a rapid response time (45 s) and a significant Stokes shift (227 nm). The characteristics of the developed probe are better than those of another probe, namely ND-DNBS, which was also synthesized by our group and most other previously reported fluorescent probes for GSH. The AND-DNBS probe was able to detect GSH via a red emission in living A549 cells and zebrafishes. These results show that AND-DNBS has potential applications as an excellent probe for detecting GSH in various environments.