Abstract: An analytical method was developed for the simultaneous determination of 14 organophosphorus pesticides in Flos Chrysanthemi by using matrix solid phase dispersion (MSPD) and gas chromatography (GC). Flos Chrysanthemi samples were extracted with acetonitrile-acetone (4:1, V/V) and cleaned up by matrix solid phase dispersion (MSPD), eluted with acetonitrile-toluene (3:1, V/V) and determined by GC with a flame photometric detector. The recovery rates of 14 organophosphorus pesticides were 84.54%～108.54% with relative standard deviation of 0.66%－6.31% at spiked levels of 0.05－1.0 mg/kg. The limit of detection was 0.01－0.04 mg/kg. The proposed method was characterized by simplicity, higher sensitivity and accuracy. The contents of dimethoate, chlorpyrifos and phosfolan in Huangshan Gongju chrysanthemum were 1.68, 0.17 mg/kg and 0.28 mg/kg, respectively, the content of chlorpyrifos in Hangbaiju chrysanthemum was 0.09 mg/kg, and the contents of dimethoate, chlorpyrifos and phosalone in Hangbaiju chrysanthemum bud were 0.25, 0.14 mg/kg and 0.08 mg/kg, respectively as determined by this method.

Key words: Chrysanthemum, organophosphorus pesticides, matrix solid phase dispersion (MSPD), gas chromatography (GC)