title: New sample preparation technique for the determination of avoparcin in pressurized hot water extracts from kidney samples.
abstract: A new approach is presented for the determination of avoparcin in tissue. Complete recovery from spiked swine kidney was achieved with hot water modified with 30% ethanol (v/v). The samples were extracted at 75 degrees C and 50 atm by accelerated solvent extraction. In situ sample clean-up was achieved by using matrix solid-phase dispersion utilizing the acrylic polymer XAD-7 HP, and by adding triethylammonium phosphate (TEAP) to the extraction solvent. The aqueous extracts were concentrated by solid-phase extraction (SPE) on the hydrophilic interaction chromatography (HILIC) material polyhydroxyethyl aspartamide. Complete analyte retention was possible during SPE when the kidney extracts were modified with 70% ethanol. A 200 A, 5 microm HILIC column with UV225 detection was used for the separation of avoparcin. The retention time was less than 15 min with 47% aqueous component in acetonitrile and 15 mM TEAP as eluent. The average recovery of avoparcin from kidney samples was 108%.
authors.affiliation: National Center for Agricultural Utilization Research, USDA, Agricultural Research Service, Peoria, IL 61604, USA. currenms@ncaur.usda.gov
authors.forename: Meredith S S
authors.initials: MS
authors.lastname: Curren
authors.forename: Jerry W
authors.initials: JW
authors.lastname: King
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000302:isolation & purification; D002853:Chromatography, Liquid / Q000379:methods*; D006020:Glycopeptides; D007668:Kidney / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents; D006020:Glycopeptides; C016249:avoparcin