Determination of residue of silthiopham in wheat by gas chromatography-mass spectrometry method

Silthiopham is a new exclusive fungicide for take-all disease of wheat.An efficient and accurate analytical approach was developed for the residue of silthiopham in wheat by gas chromatography-mass spectrometry ( GC-MS) technique.Samples were extracted with acetonitrile and purified via solid phase extraction column ( Florisil) . Then those purified samples were detected by GC-MS. The results indicated that the retention time ( RT) of silthiopham was 7.188 min. And at the amount of standard sample of 0.001, 0.01 and 0.025 mg, the average recovery rate of silthiopham were 103.3%, 86.5%, 80.9%, respectively, with the relative standard deviation ( RSD) 7.50%, 5.11%, 3.52%, separately.The linear ranges were from 0.006 to0.1 mg/kg with a good linear relationship ( R2= 0.9998) .The limit of detection was 0.002 mg/kg, and the limit of quantification was 0.006 mg/kg.Thus, this study provided a simple, rapid and effective method in determination of the residue of silthiopham in wheat.