A dual-response fluoran-phenothiazine hybrid fluorescent probe for selective sensing of Fe and ClO and cell imaging application.

Bifunctional fluorescent probes with dual-emission response attract extensive attention. A novel fluorescent probe FP, a hybrid of fluoran and phenothiazine, has been designed and synthesized for selective sensing of Fe and ClO with dual-emission changes, which involes mechanisms of Fe-promoted spirolactone ring opening and ClO-induced oxidation of phenothiazine moiety, respectively. In addition, the detection limits for Fe and ClO were estimated to be 49.1 and 35.9 nM, respectively. Significantly, FP can be employed as an tracer for the detection of Fe ions within living HeLa cells by fluorescence imaging.