title: Liquid chromatographic method for rapid determination of total avermectin B1 and 8,9-Z-avermectin B1 residues in apples.
abstract: A liquid chromatographic method has been developed and validated for the rapid determination of avermectin B1 and 8,9-Z-avermectin B1 residues in apples. The avermectins are extracted from the crop matrix with an acetonitrile-water-hexane mixture; the extract is cleaned up on an aminopropyl solid-phase extraction column. The avermectins are derivatized with trifluoroacetic anhydride and analyzed by reversed-phase liquid chromatography with fluorescence detection. Recoveries of avermectins from apples fortified with about 2-77 ppb avermectin B1a or 2-27 ppb 8,9-Z-avermectin B1a averaged 85%. The limit of quantitation is 2 ppb (signal-to-noise [S/N] ratio, 12) and the limit of detection is 1 ppb (S/N ratio, 6) for each analyte. The assay is a simple, rapid, and sensitive method for monitoring the total amount of avermectin residues in apples.
authors.affiliation: Merck & Co., Merck Research Laboratories, Three Bridges, NJ 08887-0450, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Cobin
authors.forename: N A
authors.initials: NA
authors.lastname: Johnson
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D005638:Fruit / Q000737:chemistry*; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis; D010573:Pesticide Residues / Q000032:analysis*; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D010573:Pesticide Residues; C048324:abamectin; D007559:Ivermectin