文摘
A method capable of quantifying trichlorfon and dichlorvos in shrimp atconcentrations of 20-80ng/g has been developed. Ground shrimp is homogenized in ethylacetate and centrifuged. Thesupernatant is dried completely on a rotatory evaporator. Theextract is dissolved in petroleumether, concentrated on a solid phase extraction column, and analyzed bygas chromatography usinga cool on-column inlet and a nitrogen-phosphorus detector. Theanalytes are separated from matrixcomponents using a thermal gradient on a(cyanopropyl)phenyl-methylpolysiloxane column.Themethod was validated with control shrimp fortified at 20, 40, and 80ng/g trichlorfon and dichlorvos.The average recoveries and intralaboratory coefficients ofvariations were 50-83% and 15-21%respectively.Keywords: Trichlorfon; dichlorvos; shrimp; gas chromatography;nitrogen-phosphorus detector