Field-Amplified Sample Injection-Capillary Electrophoresis for the Determination of Bisphenol A, α-Naphthol and β-Naphthol in Drinks and Lake Water

To improve the sensitivity of capillary electrophoresis, field-amplified sample injection (FASI) was developed to determine bisphenol A (BPA), alpha-naphthol (alpha-NAP) and beta-naphthol (beta-NAP) in drinks and lake water. Parameters (sample matrix, concentration of NaCl, water plug length, sample injection time and voltage) affecting FASI have been systematically investigated. Under optimum conditions, the sensitivity was improved 17.1-, 15.8- and 9.9- fold for BPA, alpha-NAP and beta-NAP, respectively. The detection limits of BPA, alpha-NAP and beta-NAP were 0.071, 0.038 and 0.081 mu g mL(-1) and the proposed method has been successfully applied to detect BPA, alpha-NAP and beta-NAP in drinks and lake water with recoveries of 82.0-109.3 %.