Direct enrichment and high performance liquid chromatography analysis of ultra-trace Bisphenol A in water samples with narrowly dispersible Bisphenol A imprinted polymeric microspheres column.

Direct injection, enrichment and high performance liquid chromatography (HPLC) analysis of ultra-trace Bisphenol A (BPA) in water samples using one narrowly dispersible BPA imprinted polymeric microspheres (MIPM) column in one analysis process was developed. One BPA imprinted MIPM that had the best globular morphology and imprinted efficiency was used as HPLC stationary phase and applied to direct analysis of ultra-trace BPA in water. The optimum direct analysis conditions were: conditioning the MIPM column with water for 10min, injecting 40mL water sample directly, eluting with 70% methanol for 13min and then 100% methanol for 7min. Under the optimum conditions, the MIPM column can simultaneously extract, enrich, separate and determine ultra-trace BPA in one analysis process with UV detector by injection of large volume water samples (40mL). The calibration graph was linear with R(2)>0.998 in the ranges from 0.1-100nmol/L BPA standard solution. The intra- and inter-day RSD are less than 9.5 and 9.6%, respectively. The limit of quantification was 0.1nmol/L. RSD for spiked tap and lake water was less than 8.9% and the recoveries were 96-101.8%. The enrichment factor for BPA was 10,000 as 40mL water sample was directly injected and analyzed.