title: Determination of trace bisphenol A in environmental water by high-performance liquid chromatography using magnetic reduced graphene oxide based solid-phase extraction coupled with dispersive liquid-liquid microextraction.
abstract: Bisphenol A (BPA), an endocrine-disrupting chemical, has received much attention from researchers and the general public. In this paper, a novel method of determining BPA at trace levels was developed, using magnetic reduced graphene oxide (rGO-Fe3O4)-based solid-phase extraction coupled with dispersive liquid-liquid microextraction (DLLME), followed by high-performance liquid chromatographic determination. The rGO-Fe3O4was prepared and then characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and vibrating sample magnetometry. The greatest saturation magnetization of rGO-Fe3O4was up to 43.8 emu g-1, which allowed rapid isolation of the rGO-Fe3O4from solutions upon applying an appropriate magnetic field. The effects of solution pH, adsorbent amount, type and volume of eluent and extraction solvent, extraction time, and salt concentration on the extraction efficiency of BPA were examined and optimized. Under the optimum conditions, an enrichment factor of 5217 and an LOD of 0.01 μg L-1for BPA were obtained. The reusability of rGO-Fe3O4for at least 12 repeated cycles without any significant decrease in the extraction recovery of BPA was demonstrated. The proposed method was applied to the determination of BPA in different real water samples, with relative recoveries of 84.8-104.9 % and RSDs of 0.8-8.3 % in the spiked concentration range 1-10 μg L-1.
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, Guangdong, 510006, China.
authors.forename: Danping
authors.initials: D
authors.lastname: Li
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, Guangdong, 510006, China. xgma@21cn.com.
authors.forename: Xiaoguo
authors.initials: X
authors.lastname: Ma
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, Guangdong, 510006, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, Guangdong, 510006, China.
authors.forename: Yumian
authors.initials: Y
authors.lastname: Yu
keywords: Bisphenol A; Dispersive liquid–liquid microextraction; Environmental water; Gas chromatography–mass spectrometry; Magnetic reduced graphene oxide; Solid-phase extraction