A cyclometalated iridium(III) complex-based luminescent probe for HCO3− and CO32− detection and its application by test strips

Abstract

A novel cyclometalated iridium(III) complex-based luminescent probe Ir-1 for HCO3− and CO32− detection has been synthesized and characterized. The probe displayed no fluorescence around 600 nm, while a more than 10-fold enhancement in fluorescence emission intensity was observed after the addition of HCO3− or CO32−, owing to the carbonate or bicarbonate combination with the hydroxyl group on the probe Ir-1 to form a hydrogen bond. Such luminescent probe worked excellently in tetrahydrofuran with a quick response time (<20 s) and the detection limits for CO32− and HCO3− were as low as 3.95 × 10−8 mol L−1 and 1.51 × 10−7 mol L−1, respectively. In addition, to facilitate the visual application process, a test strip coated with a fluorescent probe Ir-1 was prepared and this probe could also be used to detect HCO3− and CO32− in actual samples with high accuracy.