A novel imidazole derivative-based turn-on probe for rapid and sensitive detection of phosphate and carbonate in...

In this study, a novel fluorescent probe, Y, based on a thieno[2,3-b]pyrrole-dibenzimidazole scaffold, was synthesized and evaluated. Probe Y exhibited high sensitivity toward phosphate (PO₄^3-) and carbonate (CO₃^2-) in a DMSO: H₂O (9:1, v/v) medium, showing a fluorescence "turn-on" response with the emergence of an emission peak at 467 nm. Probe Y displayed strong binding affinities for both PO₄^3- and CO₃^2-, with detection limits of 0.67 μM and 0.26 μM, respectively. The recognition mechanisms were investigated using ¹H NMR and Density Functional Theory (DFT) calculations. Experiments conducted using authentic water and soil matrices confirmed probe Y's high sensitivity in complex samples. Simultaneously, probe Y was effectively employed in test strips, thereby confirming its high sensitivity. This illustrates its capacity as one of the few fluorescent probes that can concurrently detect PO₄^3-and CO₃^2-.