DLLME Combined with GC-MS for the Determination of Methylparaben, Ethylparaben, Propylparaben and Butylparaben in Beverage Samples

Dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography-mass spectrometry (GC-MS) has been developed for the determination of four parabens (methylparaben, ethylparaben, propylparaben and butylparaben) in beverage samples. Some important parameters, such as the kinds and volumes of extraction solvent and dispersive solvent, extraction time and salt effect were investigated and optimized. Under the optimum extraction conditions, the enrichment factors for methylparaben, ethylparaben, propylparaben and butylparaben were 46, 74, 166 and 240, respectively, and the detection limits (LODs) were 2.9, 1.3, 0.59 and 0.46 mu g L-1, respectively. The relative standard deviations (RSDs) for the extraction of 10 mu g L-1 of parabens were in the range of 6.5-10.8% (n = 5). The method was applied to the analysis of the four parabens in different beverages. For the analysis of the spiked samples, a recovery of 73.6-106.3% with RSDs of 1.2-11.9% were obtained