RESUMEN
Objective: No complete study has been reported on methomyl and its metabolite in rat plasma at home and abroad.This study aimed to detect methomyl and its metabolite in rat plasma by high performance liquid chromatography-mass spectrometry(HPLC-MS).Methods: Ten Wistar rats received intragastric administration of methomyl 50mg/kg,and then executed and kept at room temperature for 72 hours.After that,methomyl and its metabolite in the heart-blood of the rats were determined by solid phase extraction(SPE) and HPLC-MS.Results: Compared with the blank controls,methomyl and its metabolite were detected in the plasma of the experimental rats,and so were protonate ions and multistage fragment ions.Conclusion: The methomyl metabolite in the rat plasma was S-methyl-N-hydroxythioacetamidate.