title: Multicolumn solid-phase extraction cleanup of organophosphorus and organochlorine pesticide residues in vegetable oils and butterfat.
abstract: Diatomaceous earth columns used with reversed and normal solid phase extraction (SPE) cartridges were evaluated for the quantitative determination of a number of organophosphorus (OP) and organochlorine (OC) pesticide residues in edible vegetable oils and butterfat. An oil or fat sample (about 2 g) in hexane was passed through a diatomaceous earth (Extrelut QE) column and a C18 bonded silica (ODS) SPE cartridge, resulting in the separation of the pesticides from about 98% of the lipids. The eluate was split in half, with the first portion concentrated into acetone for the determination of OP pesticides by gas chromatography with flame photometric detection (GC-FPD). The other half was passed through an Alumina-N SPE cartridge for additional cleanup of lipid matrix to determine OC pesticides by GC with electron-capture detection (GC-ECD). Average recoveries from fortified samples were greater than 89% for the pesticides studied.
authors.affiliation: U.S. Food and Drug Administration, Pesticides and Industrial Chemicals Research Center, Detroit, MI 48207, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Gillespie
authors.forename: S L
authors.initials: SL
authors.lastname: Daly
authors.forename: D M
authors.initials: DM
authors.lastname: Gilvydis
authors.forename: F
authors.initials: F
authors.lastname: Schneider
authors.forename: S M
authors.initials: SM
authors.lastname: Walters
mesh_terms: D002079:Butter / Q000032:analysis*; D002849:Chromatography, Gas / Q000379:methods*; D006843:Hydrocarbons, Chlorinated; D007306:Insecticides / Q000032:analysis* / Q000302:isolation & purification; D009943:Organophosphorus Compounds; D010938:Plant Oils / Q000737:chemistry*
chemical_list: D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; D009943:Organophosphorus Compounds; D010938:Plant Oils; D002079:Butter