title: [Gas chromatographic method for the analysis of residues of seven penicillins in food of animal origin].
abstract: A capillary gas chromatographic method is described for the determination of residues of benzylpenicillin, phenoxymethylpanicillin, methicillin, oxacillin, cloxacillin, dicloxacillin and nafcillin in bovine muscle, liver, kidney, adipose tissue and milk. The samples are extracted with acetonitrile under slightly acidic conditions, the co-extracted water is separated with the addition of sodium chloride and dichloromethane and discarded. Clean-up is performed by liquid/liquid partitioning steps and anion exchange chromatography. The penicillin residues are methylated with diazomethane. After derivatization, only the extracts from liver and kidney needed further clean-up using cartridges with a polar diol sorbent. The gas chromatographic procedure is based on split/splitless injection, programmed temperature vaporization, separation on a methyl silicone fused silica column and nitrogen-specific thermionic detection. Internal standardization is used for quantification. The limits of detection for all penicillins are well below 3 microgram/kg in milk and all tissues. Recoveries of spiked samples at 3 and 10 micrograms/kg are in the range of 65-80% for milk and 50-70% for bovine tissues.
authors.affiliation: Bergische Universität Wuppertal, Bundesrepublik Deutschland.
authors.forename: U
authors.initials: U
authors.lastname: Meetschen
authors.forename: M
authors.initials: M
authors.lastname: Petz
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry; D000818:Animals; D002417:Cattle; D002849:Chromatography, Gas; D002852:Chromatography, Ion Exchange; D004350:Drug Residues / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D007668:Kidney / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008460:Meat / Q000032:analysis*; D008892:Milk / Q000032:analysis*; D009132:Muscles / Q000737:chemistry; D010406:Penicillins / Q000032:analysis*
chemical_list: D010406:Penicillins
vernacular_title: Gaschromatographische Analysenmethode für Rückstände von sieben Penicillinen in Lebensmitteln tierischen Ursprungs.