Abstract: A method to simultaneously determine 43 pesticide residues in coix seed is described in this paper. Samples were extracted by accelerated solvent extraction (ASE), cleaned up by either solid phase extraction (SPE) or gel permeation chromatography (GPC), and analyzed by gas chromatography-mass spectrometry (GC-MS). The spike recoveries obtained by SPE and GPC were 72.45%－111.74% and 74.70%－106.49%, and the RSDs 1.47%－5.06% and 1.58%－5.08%, respectively.  Correlation coefficients between 1.47% and 5.06% were found for the established calibration curves. The limits of detection (LOD) of the method varied from 0.002 to 0.02 mg/kg, and the limits of quantification (LOQ) from 0.005 to 0.05 mg/kg. The method was efficient, accurate, sensitive and applicable for the simultaneous determination of multiple pesticide residues in coix seed.

Key words: coix seed, pesticide residue, accelerated solvent extraction (ASE), solid phase extraction (SPE), gel permeation chromatography (GPC), gas chromatography-mass spectrometry (GC-MS)