Micelle-Mediated Extraction Prior to LC-UV for Preconcentration and Determination of Trace Amounts of Bisphenol A in Environmental Samples

Abstract

A simple and high sensitive preconcentration method based on micelle-mediated extraction followed by high performance liquid chromatography (LC-UV) was developed for preconcentration and determination of trace amounts of bisphenol A (BPA) in aqueous samples. The BPA was quantitatively extracted from aqueous samples in the presence of Triton X-114 as a nonionic surfactant and preconcentrated into the small volume (about 30 μ L) of the surfactant-rich phase. Taguchi method, an orthogonal array design (OA 16 (4 5 )), was utilized to optimize the various factors affecting the micellar extraction of BPA. The maximum extraction efficiency of BPA was obtained at pH 3, 0.2% (w/v) Triton X-114, and 0.25 mol L −1 sodium acetate. For the preconcentration, the solutions were incubated in a thermostatic water bath at 50°C for 7 min. After centrifuge and separation of aqueous phase, the surfactant-rich phase was diluted with 100 μ L acetone and injected in the chromatographic system. Under the optimum conditions, preconcentration factor of 34.9 was achieved for extraction from 10 mL of sample solution and the relative standard deviation (RSD%) of the method was lower than 6.6%. The calibration curve was linear in the range of 0.5–150 μ g L −1 with reasonable linearity ( r 2 > 0.9987 ). The limit of detection (LOD) based on S / N = 3 was 0.13 μ g L −1 for 10 mL sample volumes. The limit of quantification (LOQ) based on S / N = 10 was 0.43 μ g L −1 for 10 mL sample volumes. Finally, the applicability of the proposed method was evaluated by the extraction and determination of BPA in the real samples, and satisfactory results were obtained.