Thin-film microextraction for the preconcentration of some endocrine disrupting chemicals in aqueous samples before chromatographic analysis

Poly(vinylidene fluoride) (PVDF) has attracted enormous attention as a membrane material with regard to its excellent properties in recent years. In this paper, a new sample preparation technique, the PVDF membrane as the extraction phase, has been applied to the extraction of four endocrine-disrupting compounds: bisphenol A (BPA), 4-t-octylphenol (4-t-OP), nonylphenot (NP), and 4-nonylphenol (4-NP) from water samples for the first time, prior to their determination by high performance liquid chromatography-ultraviolet detection. Some important experimental parameters affecting the extraction efficiency were optimized. Good linearity was observed over the concentration range of 1.0-100.0 ng mL(-1) for BPA, and 2.0-100 ng mL(-1) for 4-t-OP, NP and 4-NP with the correlation coefficients (r) greater than 0.9934. The limit of detection (S/N = 3) of the method was 0.2 ng mL(-1) for BPA and 0.4 ng mL(-1) for 4-t-OP, NP and 4-NP. The method is convenient, cost effective and can be a useful alternative approach for the extraction and determination of the endocrine-disrupting compounds in water samples.