A Sulphur Dioxide-Selective Sensing Membrane Based on Fluorescence Quenching
ZENG Hui-Hui , WANG Ke-Min, QIN Zhen, YU Ru-Qin (Department of Chemistry and Chemical Engineering, Htman University, Changsha, 410082)
A new reversible optical sensing membrane for the determination of sulphur dioxide based on fluorescence quenching of anthracene dissolved in plasticized poly(vinylchloride) has been developed. This chemical recognition process is accompanied by a change in the fluorescence spectrum of anthracene. With the optimum sensing membrane described, sulphur dioxide in sample solution from 6. 59×10-3 mol/L to 5. 23×10-1 mol/L can be determined. The calibration curve for sulphur dioxide shows a good correlation with the theoretically derived formulae and thus confirms the theoretically expected behavior. Besides a high reproducibility of the optical signals, the very short response time between 5 to 30 s was realized. The optical sensing membrane presented exhibits a good selectivity for sulphur dioxide.