Sensitive Fluorescent Sensor for Hydrogen Sulfide in Rat Brain Microdialysis via CsPbBr Quantum Dots.

The instability and insolubility of perovskite quantum dots in aqueous solution prohibit applications in polar solvents. As a highly toxic gas pollutant and also an endogenous gaseous signaling molecule existing in a variety of physiological processes, hydrogen sulfide (HS), with high selectivity and high specificity, detection is of great significance. In this study, a simple device has been designed to separate HS from aqueous solution and CsPbBr quantum dots (CsPbBr QDs) have been used as the detection probe to develop a novel fluorescent sensor for rapid HS detection. The addition of hydrogen sulfide to the phosphoric acid solution results in the escape of HS from the aqueous sample and hence it passing into the -hexane solution containing CsPbBr QDs, resulting in the quenching of the fluorescence of CsPbBr QDs. The fluorescence intensity of the system has a linear relationship with the concentration of HS in the range of 0-100 μM with the detection limit of 0.18 μM. The proposed system has been applied to detection of HS in rat brain microdialysate with satisfying results. The potential mechanism regarding the quenching of fluorescence from CsPbBr QDs by HS has been studied as well.