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

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 x 10(-8) mol L-1- and 1.51 x 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 Co-3(2-) in actual samples with high accuracy.