Determination of 193 pesticide residues in vegetables and fruits by gas chromatography-mass spectrometry

On the basis of optimization of solid phase extraction adsorbent, eluting solvent types and amounts, a gas chromatography-mass spectrometric method was developed for the determination of 193 pesticide residues in vegetables and fruits. The analytes were extracted from the samples using acetonitrile. The extract was cleaned-up with a C18/PSA solid-phase extractor, eluted by acetonitrile and analyzed by GC-MS under selected ion monitoring (SIM) mode using triphenyl phosphate (TPP) as internal standard. The linear range was from 10 to 1 000 microg/L for 130 pesticides, from 20 to 1 000 microg/L for 34 pesticides, from 50 to 1 000 microg/L for 26 pesticides, from 100 to 1 000 microg/L for the other 3 pesticides with the good correlation coefficients (r > or = 0.996 7). The limits of detection were 0.04 - 8.26 microg/kg. The mean recoveries of the pesticides were 71.6% -117.9%. The relative standard deviations were 3.0% - 11.8%. This method is simple, rapid, sensitive and specific. It is appropriate for the simultaneous identification and quantification of the multi-residues in fruits and vegetables.