title: Determination of antibiotics such as macrolides, ionophores and tiamulin in liquid manure by HPLC-MS/MS.
abstract: A method for the analysis of several macrolide and ionophore antibiotics as well as tiamulin in liquid manure was developed. Reversed-phase liquid chromatography and atmospheric pressure chemical ionisation (APCI) tandem mass spectrometry was used for detection.High-performance liquid chromatographic (HPLC) separation of the antibiotics was achieved in 35 min. The analytes were extracted with ethyl acetate and the extracts were cleaned up by solid-phase extraction on a diol SPE cartridge. Recovery experiments with spiked liquid manure concentrations varying from 6 to 2,000 microg kg(-1) gave constant recovery rates. The recovery rates for the macrolides erythromycin, roxithromycin and oleandomycin were 75-94%, that for the ionophore salinomycin was 119%, while that for the pleuromutilin tiamulin was 123%, when using a macrolide internal standard. The relative standard deviation was found to be 15-36% and the limits of detection were 0.4-11.0 micro g kg(-1). The maximum concentrations found in manure samples were 43 micro g kg(-1) for tiamulin and 11 micro g kg(-1) for salinomycin.
authors.affiliation: Institute of Environmental Research, Otto-Hahn-Str. 6, 44227 Dortmund, Germany. m.schluesener@infu.uni-dortmund.de
authors.forename: Michael P
authors.initials: MP
authors.lastname: Schlüsener
authors.forename: Kai
authors.initials: K
authors.lastname: Bester
authors.forename: Michael
authors.initials: M
authors.lastname: Spiteller
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D004224:Diterpenes / Q000032:analysis; D007476:Ionophores / Q000032:analysis; D018942:Macrolides; D008372:Manure / Q000032:analysis*; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents; D004224:Diterpenes; D007476:Ionophores; D018942:Macrolides; D008372:Manure; C014224:tiamulin