title: Simultaneous determination of residual thiamphenicol and florfenicol in foods of animal origin by HPLC/electrospray ionization-MS/MS.
abstract: A simple and reliable method using HPLC/MS/MS has been developed for determination of thiamphenicol and florfenicol in foods of animal origin, such as pork, porcine liver, porcine kidney, beef, bovine liver, fish, and chicken. The HPLC separation was performed on a Waters XTerra phenyl column (100 x 2.1 mm, 3.5 microm) with a gradient mobile phase system of 0.1% formic acid-methanol at a flow rate 0.35 ml/min. Negative ionization produced the molecular ions at m/z 354 and 356 for thiamphenicol and florfenicol, respectively. Two characteristic transition reactions (m/z 354-->185, 290 and m/z 356-->336, 185) in the selected reaction monitoring mode were tested for detection and confirmation of thiamphenicol and florfenicol simultaneously. The analytes were extracted with ethyl acetate and defatted with n-hexane by liquid-liquid extraction. The recoveries of thiamphenicol and florfenicol by the developed method were 72.5-97.6%. The limits of determination were 1.0 ng/g (ppb) for both compounds.
authors.affiliation: Bureau of Food and Drug Analysis, Department of Health, Executive Yuan, No.161-2, Kunyang St, Nangang District, Taipei City 115-61, Taiwan, Republic of China.
authors.forename: Kuang Yu
authors.initials: KY
authors.lastname: Chou
authors.forename: Tsung Yao
authors.initials: TY
authors.lastname: Cheng
authors.forename: Ching Mei
authors.initials: CM
authors.lastname: Chen
authors.forename: Pei Ling
authors.initials: PL
authors.lastname: Hung
authors.forename: Yu Yun
authors.initials: YY
authors.lastname: Tang
authors.forename: Yueh Jong
authors.initials: YJ
authors.lastname: Chung-Wang
authors.forename: Yang-Chih
authors.initials: YC
authors.lastname: Shih
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002417:Cattle; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D004350:Drug Residues; D005399:Fishes; D007202:Indicators and Reagents; D008460:Meat / Q000032:analysis*; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization; D013552:Swine; D013839:Thiamphenicol / Q000031:analogs & derivatives* / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D007202:Indicators and Reagents; D012996:Solutions; C035534:florfenicol; D013839:Thiamphenicol