Determination of triazine pesticides in honey by ultra high performance liquid chromatography-high resolution isotope dilution mass spectrometry combined with dispersive micro-solid phase extraction

A novel dispersive micro-solid phase extraction (DMSPE) method based on a polymer cation exchange material (PCX) sorbent was applied to the simultaneous determination of 5 triazine pesticides in honey using ultra high performance liquid chromatography-high resolution isotope dilution mass spectrometry (UHPLC-HRIDMS). Samples were first extracted with 1% formic acid in acetonitrile/water (1 : 1 v/v) and then cleaned up by the DMSPE procedure. Several important parameters affecting the extraction efficiency in the PCX-DMSPE method, such as the amount of PCX sorbent, the pH, the adsorption time, the type and volume of the desorption solvent were carefully investigated and optimized. Under the optimum extraction conditions, the method showed a good linearity (r > 0.999) in the studied range for each analyte. The LOD values of 5 triazine pesticides ranged from 0.02 mu g kg(-1) to 0.2 mu g kg(-1), with recoveries in the range of 89.8-116.2%. The precision of the method, calculated as relative standard deviation (RSD), was better than 8.7% for 5 triazines. The results showed that the proposed method, based on the PCX-DMSPE procedure, had the advantages of convenience and high efficiency and was successfully applied to analyze 5 triazine pesticides in honey.