Veterinary Drugs Residue Methods


Category Anticoccidials, including nitroimidazoles
Drug Class Name Lasalocid, Anticoccidial, antibiotic, ionophore, growth promoter
Method Title Lasalocid in Bovine Tissue
Method Date 1991/07/01
Method Type Screening, Quantitative
Scope and Application This method is suitable for screening (and quantifying) the presence of Lasalocid in bovine liver.
Method Summary Homogenized liver samples (partially defrosted where applicable) are extracted in acetonitrile by centrifugation. Hexane is added and centrifugation repeated to remove fat. Most of the acetonitrile is evaporated before adding chloroform to the extract. This mixture is then filtered through a Sep-Pak silica cartridge and evaporated to dryness. The residue is dissolved in the mobile phase and centrifuged again. The upper layer of this extract is then analyzed using an HPLC connected to a fluorometer. Two Whatman Partisil PXS 10/25 analytical columns connected in series are used.
Applicable Concentration Range Lasalocid may be detected in bovine liver at ≥ 25 µg kg-1 concentration level.
QC Requirements See attached SOP
Method Source USDA-FSIS
Method SOP PDF icon SOP 
Citation Citation