title: Single-step extraction followed by LC for determination of (fluoro)quinolone drug residues in muscle, eggs, and milk.
abstract: In this study, a simplified method for the extraction and determination of seven fluoroquinolone residues (danofloxacin, difloxacin, enrofloxacin, marbofloxacin, orbifloxacin, ofloxacin, and sarafloxacin) and three quinolones (oxolinic acid, flumequine, and nalidixic acid), in porcine muscle, table eggs, and commercial whole milk, which required no cleanup step, was devised. This procedure involves the extraction of analytes from the samples via liquid-phase extraction, and the subsequent quantitative determination was accomplished via LC-fluorescence detection. Analyte separation was successfully conducted on an XBridge-C(18) column, with a linear gradient mobile phase composed of acetonitrile and 0.01 M oxalic acid buffer at pH=3.5. The one-step liquid-liquid extraction method evidenced good selectivity, precision (RSDs=0.26-15.07%), and recovery of the extractable analytes, ranging from 61.12 to 115.93% in matrices. The LOQs ranged from 0.3 to 25 microg/kg. A survey of ten samples purchased from local markets was conducted, and none of the samples harbored fluoroquinolone residues. This method is an improvement over existing methodologies, since no additional cleanup was necessary.
authors.affiliation: Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul, Republic of Korea.
authors.forename: Hee-Jung
authors.initials: HJ
authors.lastname: Cho
authors.forename: Hee
authors.initials: H
authors.lastname: Yi
authors.forename: Soo Min
authors.initials: SM
authors.lastname: Cho
authors.forename: Dong Goo
authors.initials: DG
authors.lastname: Lee
authors.forename: Kyul
authors.initials: K
authors.lastname: Cho
authors.forename: A M
authors.initials: AM
authors.lastname: Abd el-Aty
authors.forename: Jae-Han
authors.initials: JH
authors.lastname: Shim
authors.forename: Soon-Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Ji-Yoon
authors.initials: JY
authors.lastname: Jeong
authors.forename: Ho-Chul
authors.initials: HC
authors.lastname: Shin
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004350:Drug Residues / Q000032:analysis*; D004531:Eggs / Q000032:analysis*; D008163:Luminescent Measurements; D008892:Milk / Q000737:chemistry*; D018482:Muscle, Skeletal / Q000737:chemistry*; D015363:Quinolones / Q000032:analysis*; D015203:Reproducibility of Results; D013552:Swine
chemical_list: D015363:Quinolones