A simple and rapid method known as matrix solid phase dispersion(MSPD) for simultaneous determination of 11 pesticide(2,4,5,6-tetrachlor m-xylene, α-BHC, γ-BHC, δ-BHC, aldrin, chlorfulazuron, heptachloroepoxide, dieldrine, endrin, endosulfan sulfate, and tetradifon) in beef fat was estabilished. Beef fat(0.5g) was fortified by adding the 11 pesticides and dibutylchlorendate as internal standard, and blended with 2g bulk C_(18) in pestle and motar.
Pesticides were eluted from an extraction column composed of C_(18)/ fat matrix blend and 2g activated Florisil by addition of 8㎖ acetonitrile. Then 2㎕ portion of the acetonitrile elute was directly analyzed by gaschromatography with electron capture detection. Unfortified blank control were treated similarly. Recovery rate were ranged from 83±5.4% to 94.2±7.6%, intra-assay variability and inter-assay variability were ranged from 2.3% to 7.4%(n=5 for each insecticides) and from 6±1% to 12±3%(n=10 for each insecticides), respectively.
These results indicated that the MSPD methodology is aceptable for the extraction, determination and screening of residues 11 chroniated pesticides in beef fat.
|