A new method,based on surfactant assisted dispersive liquid-liquid microextraction on solidification of floating organic droplets(SA-DLLME-SFO),followed by high performance liquid chromatography(HPLC) with diode array detector(DAD) was developed for the enrichment and determination of p-nitrophenol,p-cresol,p-bromophenol and bisphenol A in environmental-water samples.1-Dodecanol was utilized as extractant in the SA-DLLME-SFO method.A conventional nonionic surfactant,Tween 20,was used as a disperser agent in this approach.Parameters affecting the extraction efficiency of the SA-DLLME-SFO method such as volume of extraction solvent and nonionic surfactant,extraction and centrifugation time,salt effect were investigated.Under the optimized conditions,the detection limits of p-nitrophenol,p-cresol,p-bromophenol and bisphenol A were 0.13,0.13,1.02,0.25 ng/mL,respectively.The calibration curves were linear in the range of 2-4 000 ng/mL for p-nitrophenol,p-cresol,bisphenol A,and 10-4 000 ng/mL for p-bromophenol.The recoveries of four compounds at spiked levels of 02 μg/mL and 0.8 μg/mL were in the range of 96.6%-105%,with relative standard deviations(RSD,n=5) of 1.9%-4.9%.The proposed method was successfully applied in the analysis of p-nitrophenol,p-cresol,p-bromophenol and bisphenol A in pond water and lake water. |