Rhodamine-benzothiazole-thiophene: A triangular molecular tool for simultaneous detection of Hg2+ and Cu2+

A novel rhodamine-benzothiazole fluorescent chemosensor, bridged with a thiophene unit, is designed for the turn-on detection of Hg 2+ and Cu 2+ . Noteworthy findings include impressively low limits of detection (0.007 μM for Hg 2+ and 0.013 μM for Cu 2+ ), a determined sensing mechanism involving spirolactam ring opening and hydrolytic cleavage, consistent 1:1 binding stoichiometry for both metal ions and an optimal pH of around 6. The sensor’s practical applicability is demonstrated through successful implementation in HeLa cells and zebrafish, along with effective analyte recovery in various water samples. This work advances the field by providing a highly sensitive and versatile chemosensor for environmental and biological applications.