Cloud point extraction for the determination of bisphenol A, bisphenol AF and tetrabromobisphenol A in river water samples by high-performance liquid chromatography

In this work, cloud point extraction (CPE) was developed for the preconcentration and separation of bisphenol A (BPA), bisphenol AF (BPAF) and tetrabromobisphenol A (TBBPA) prior to high-performance liquid chromatography (HPLC) analysis. Firstly, alcohol ethoxylate (AEO9) was applied as the extractant and octanol worked as the cloud point revulsant and synergic reagent for extraction, which decreased the cloud point temperature (CPT) of AEO9 from 75 °C to 30 °C and assisted the subsequent extraction. The parameters influencing the CPE efficiency, such as AEO9 concentration, octanol volume, pH value, extraction time and temperature were systematically evaluated. Under the optimum conditions, the linear range of BPA, BPAF and TBBPA was from 0.05 to 25 mg L−1. All correlation coefficients of the calibration curves were more than 0.9988. The relative standard deviations (RSD, n = 5) were 1.6–4.7%. The limits of detection (LOD) were in the range of 0.27–0.32 μg L−1 and the limits of quantification (LOQ) were in the range of 0.71–0.98 μg L−1. The proposed method was successfully applied to the extraction of BPA, BPAF and TBBPA in river water samples as a rapid, simple, and sensitive method.