title: Improved clean-up for the determination of lasalocid in 'difficult' food matrices.
abstract: Methodology has been developed for the determination of lasalocid in analytically 'difficult' matrices such as processed and spiced foods. The procedure was based on an existing silica-based solid-phase extraction (SPE) clean-up to which was added a novel NH2 SPE step before HPLC with fluorescence detection. Use of the additional step enabled the determination of lasalocid in matrices such as baby food, meat pies ('pasties'), etc. Analysis of these matrices was not possible using the standard clean-up on its own. Chromatography showed a massive reduction in the amount of co-extractives and interferences. Validation data were obtained down to the 10-40 mg kg(-1) level for a range of products. Recoveries ranged from 74% at 10 microg kg(-1) for pork sausages to 96% at 40 microg kg(-1) for meat pies.
authors.affiliation: Central Science Laboratory, Sand Hutton, York, UK. j.tarbin@csl.gov.uk
authors.forename: J A
authors.initials: JA
authors.lastname: Tarbin
authors.forename: E
authors.initials: E
authors.lastname: Rawlings
authors.forename: D
authors.initials: D
authors.lastname: Tyler
authors.forename: M
authors.initials: M
authors.lastname: Sharman
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003049:Coccidiostats / Q000032:analysis*; D004350:Drug Residues / Q000032:analysis*; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D005511:Food Handling; D006801:Humans; D007832:Lasalocid / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D003049:Coccidiostats; D007832:Lasalocid