Rapid determination of bisphenol A in drinking water using dispersive liquid-phase microextraction with in situ derivatization prior to GC-MS.

This paper described a novel approach for the determination of bisphenol A by dispersive liquid-phase microextraction with in situ acetylation prior to GC-MS. In this derivatization/extraction method, 500 microL acetone (disperser solvent) containing 30.0 microL chlorobenzene (extraction solvent) and 30.0 microL acetic anhydride (derivatization reagent) was rapidly injected into 5.00 mL aqueous sample containing bisphenol A and K2CO3 (0.5% w/v). Within a few seconds the analyte was derivatized and extracted at the same time. After centrifugation, 1.0 microL of sedimented phase containing enriched analyte was determined by GC-MS. Some important parameters, such as type and volume of extraction and disperser solvent, volume of acetic anhydride, derivatization and extraction time, amount of K2CO3, and salt addition were studied and optimized. Under the optimum conditions, the LOD and the LOQ were 0.01, 0.1 microg/L, respectively. The experimental results indicated that there was linearity over the range 0.1-50 microg/L with coefficient of correlation 0.9997, and good reproducibility with RSD 3.8% (n = 5). The proposed method has been applied for the analysis of drinking water samples, and satisfactory results were achieved.