A dual chemiluminescence and ratiometric fluorescence sensor based on WS2 QDs- Fe(II)- S2O82− system for bisphenol A detection

Abstract

Bisphenol A (BPA) is an environmental containment with toxic and hazardous characteristics towards all organisms. So, introducing a simple and sensitive sensor for its determination in the field is of importance. We applied Fe(II) -S2O82− Fenton-like reaction to design chemiluminescence and fluorescence sensing methods for BPA detection. In the chemiluminescence method, tungsten disulfide quantum dots (WS2 QDs) were used as an enhancer to amplify (around 300-fold) the intensity of the ultra-weak Fe(II) -S2O82− CL reaction. The WS2 QD-enhanced CL system was applied to design a simple and sensitive sensor for monitoring BPA at the range of 1.0–50 μM. Additionally, a ratiometric fluorescence sensor was designed for BPA assay in which WS2 QDs and o-phenylenediamine (OPD) were applied as a reference and a fluorescence reporter, respectively. In the presence of BPA, the fluorescence intensity of ox-OPD, produced from the OPD-Fe(II) -S2O82− reaction, increased while that of WS2 QDs was almost constant. The ratio of reporter fluorescence intensity to that of the reference was linearly proportional to the BPA concentration in the range of 2.5–75 μM. The developed methods were successfully applied for the determination of BPA in water samples.