title: Simultaneous determination of 13 quinolones in eggs using column high-performance liquid chromatography/electrospray ionization-tandem mass spectrometry and depletion of pefloxacin methanesulfonate in eggs.
abstract: An efficient method was developed for simultaneous determination of 13 quinolones--namely, enoaxacin (ENO), marbofloxacin (MAR), ciprofloxacin (CIP), norfloxacin (NOR), ofloxacin (OFL), pefloxacin methanesulfonate (PEF), danofloxacin (DAN), enrofloxacin (ENR), lomefloxacin (LOM), difloxacin (DIF), sarafloxacin (SAR), oxolinic acid (OXO), and flumequine (FLU)--in eggs by column liquid chromatography/electrospray ionization-tandem mass spectrometry. Samples were extracted with a phosphoric acid-phosphate buffer followed by purification with a solid-phase extraction cartridge. Recoveries for the 13 quinolones were 67-93% with intraday and interday coefficients of variation ranging from 4 to 9% and 2 to 18%, respectively. The limit of determination was 0.05 microg/kg for OXO and FLU; 0.1 microg/kg for MAR, OFL, CIP, LOM, DAN, SAR, DIF, NOR, and ENR; and 0.2 microg/kg for ENO and PEF. The method was also applied to study the depletion of PEF in eggs. The concentration of PEF increased and reached a maximum value on the third day, and then decreased rapidly until it could not be detected on day 32; its metabolite NOR was detectable on the second day, and then reached a maximum on the sixth day, after which it could not be detected until day 15.
authors.affiliation: China Agriculture University, College of Veterinary Medicine, Department of Pharmacology and Toxicology, Beijing 100094, People's Republic of China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Shen
authors.forename: Haiyan
authors.initials: H
authors.lastname: Li
authors.forename: Haiyang
authors.initials: H
authors.lastname: Jiang
authors.forename: Degang
authors.initials: D
authors.lastname: Zhou
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Li
authors.forename: Shuangyang
authors.initials: S
authors.lastname: Ding
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004531:Eggs / Q000032:analysis*; D005260:Female; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D015366:Pefloxacin / Q000032:analysis*; D015363:Quinolones / Q000032:analysis*; D012015:Reference Standards; D015203:Reproducibility of Results; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D000900:Anti-Bacterial Agents; D007202:Indicators and Reagents; D015363:Quinolones; D012996:Solutions; D015366:Pefloxacin