Matrix solid-phase dispersion coupled with gas chromatography-tandem mass spectrometry for simultaneous determination of 13 organophosphate esters in vegetables

In this study, matrix solid-phase dispersion coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the analysis of 23 organophosphate esters (OPEs) in vegetables. Under the optimal conditions, 0.5 g vegetables was dispersed with use of 2 g Florisil, 2 g anhydrous sodium sulfate, and 0.1 g graphitized carbon black, and it was transferred to an empty solid-phase extraction cartridge. The analytes were eluted with 15 mL n-hexane/acetone (1: 1, v/v) and analyzed by GC-MS/MS. The method detection limits and quantitation limits ranged from 0.05 to 0.33 ng/g and from 0.16 to 1.10 ng/g, respectively. The recoveries ranged from 65.1% to 109.1%, and the relative standard deviations were less than 15%. The analysis of eight kinds of vegetables shows that the vegetables had been contaminated by OPEs; the concentrations of the sum of the OPEs ranged from 5.89 to 26.8 ng/g. The proposed method is applicable to analyze OPEs in vegetables.