Development of an HPLC-MS/MS method for the simultaneous analysis of six kinds of parabens in food

Parabens (the esters of 4-hydroxybenzoic acid) are widely used as preservatives in thousands of foods, cosmetics and pharmaceutical products. A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for the quantification of six kinds of parabens in food. The method was shown to be quantitative for the methyl, ethyl, propyl, butyl, isopropyl and isobutyl esters of 4-hydroxybenzoic acid. Samples were extracted by acetonitrile and cleaned up by solid phase extraction columns of LC-C-18. Analysis was carried out by HPLC-MS/MS in a 15 min run time using atmospheric pressure electrospray ionisation in the negative mode (ESI-) and multiple reaction monitoring (MRM) scanning. The calibration curve was linear over a range of 10-1000 mu g L-1 for parabens, and the limit of quantification (LOQ) was 10 mu g L-1. The recovery of the method was 84.5-108.8% and values for intraday and interday precision were between 1.16 and 9.21%. The method was successfully applied in the determination of parabens in food samples.