One-Step Constructed Electrochemiluminescence Sensor Coupled with Magnetic Enhanced Solid Phase Microextraction to Sensitively Detect Bisphenol-A

In the present study, an electrochemiluminescence quenching approach coupled with magnetic enhanced solid phase microextraction was exploited for the extraction and determination of bisphenol A. The GO-Fe3O4 nanocomposites as solid phase microextraction sorbent were synthesized for extraction of bisphenol A. It was found that the magnetic field applied using an external magnet can not only achieve rapid separation, but also enhance the extraction efficiency to some extent. The GO Au nanoparticle (GO-AuNPs) composites combine the advantages of large specific surface area of graphene oxide and good conductivity of Au nanoparticles. Thus, an electrochemiluminescence sensor was constructed by immobilization of GO-AuNPs composites on glassy carbon electrodes (GCE). Bisphenol A could quench GO-AuNPs composites enhanced electrochemiluminescence signal of luminol during the detection stage. Under optimized experimental conditions, the quenched electrochemiluminescence intensity was linearly proportionally to the negative value of the logarithm of the concentration of bisphenol A within the range of 10(8)-10(4) mol/L, with a correlation coefficient r of 0.9920 and a limitation of detection of 4.2 x 10 mol/L. This method can be used to detect bisphenol-A in real samples, meanwhile its sensitivity was higher based on the enhancing effect of luminol by GO-AuNPs composites and extraction of target before detection.