title: Measurement of ampicillin residue levels in chicken eggs during and after medicated feed administration by LC-MS/MS.
abstract: A simple and sensitive LC-MS/MS method was developed and validated for the determination of ampicillin (ABPC) in chicken eggs. Residues were extracted by reverse-phase solid-phase extraction. Chromatographic separation was performed using a reverse-phase column with an elution gradient. The limits of detection and quantification were 0.01 and 0.1 ng g(-1), respectively. For the 0.1-50 ng g(-1) concentration range, mean recovery and accuracy values were 93.9-98.5% and 100.2-118.0%, respectively. ABPC residue concentrations in eggs before, during and after 7 days of medicated feeding of maximum dosage (40 mg kg(-1) body weight day(-1)) of ABPC were determined with the LC-MS/MS method. The maximum concentration of ABPC in eggs was 3.6 ± 1.7 ng g(-1) (mean ± SD) on the last day of the administration period. Residue concentrations of ABPC in eggs during and after ABPC administration were not over the Japanese maximum residue limit of 0.01 mg kg(-1).
authors.affiliation: a National Veterinary Assay Laboratory, Ministry of Agriculture , Forestry and Fisheries , Kokubunji , Tokyo , Japan.
authors.forename: Kouko
authors.initials: K
authors.lastname: Hamamoto
authors.forename: Ryoko
authors.initials: R
authors.lastname: Akama
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Mizuno
mesh_terms: D000667:Ampicillin / Q000008:administration & dosage / Q000032:analysis*; D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002645:Chickens; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis; D004355:Drug Stability; D004531:Eggs / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis; D007564:Japan; D008452:Maximum Allowable Concentration; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; D000667:Ampicillin
keywords: ampicillin; animal products – chicken egg; chromatography – LC-MS/MS; medicated feed; residue study; stability