[Two sample pretreatment methods and their applications in the determination of 111 pesticides and related chemicals in aquatic products].
Two sample pretreatment methods were developed and applied to determine 111 residues of pesticides in aquatic products. For Method I, the residues were extracted from homogenized tissue with acetone-ethylacetate-n-hexane (1 : 1 : 1, v/v/v), and then were redissolved in acetonitrile; for Method II, the residues were extracted from homogenized tissue with acetonitrile - water under ultrasonication, and then were separated by liquid-liquid partition. The supernatants were purified using solid phase extraction (Envi-18 and PSA columns) prior to the GC-MS analysis. The determination was performed in selected ion monitoring (SIM) mode with the external calibration for quantitative analysis. Under the optimal conditions, the detection limits (S/N = 3) for residues of pesticides were in the ranges of 0.001 -0.026 mg/kg. The recoveries of Method I for the spiked standards at concentration of 0.25 mg/kg were 72% - 113% with the relative standard deviations (RSDs) of 3.4% - 12.1%. The recoveries of Method II were 51% - 127%, among which the recoveries for 94% pesticides were between 70% and 120% with the RSDs of 3.2% - 13.8%.
Su
Jianfeng
J
Fujian Fairreach Food Safety Testing Co., Ltd., Fuzhou 350015, China. sujianfeng@fairreach.com
Lin
Guyuan
G
Lian
Wenhao
W
Zhang
Jinhu
J
Chen
Donghu
D
D053000:Analytic Sample Preparation Methods / Q000379:methods*; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D057230:Limit of Detection; D016014:Linear Models; D010573:Pesticide Residues / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification*; D017747:Seafood / Q000032:analysis*; D012997:Solvents / Q000737:chemistry
D010573:Pesticide Residues; D012997:Solvents