title: Sample preparation strategy for the simultaneous determination of macrolide antibiotics in animal feedingstuffs by liquid chromatography with electrochemical detection (HPLC-ECD).
abstract: A novel and suitable clean-up method that allows, for the first time, the simultaneous determination of a rather large number of macrolide antibiotics (erythromycin, rosamicin, spiramycin, tylosin, kitasamycin and josamycin in feedingstuffs by high performance liquid chromatography with electrochemical detection (HPLC-ECD) is presented in this work. The effectiveness of the developed clean-up method allows the quantification of the target macrolides in poultry feed using standard calibration curves instead of matrix matched standards, which overcomes the general problem of finding representative blanks. Furthermore an additional back extraction included in the sample preparation procedure allows the determination of an additional macrolide (oleandomycin) with detection limits, expressed as apparent concentration in poultry feed, ranging from 0.04 to 0.22 mg kg(-1) and relative standard deviation values ranging from 3.6 to 10.1% depending on the target analyte. Moreover, this additional step has been proven to enlarge the scope of the method by the extension of its applicability, at the target level of concentration, to other animal feedingstuffs such as pig and cattle. The analysis of real feedingstuffs containing macrolides demonstrated the fitness for purpose of the whole analytical procedure as well as a good fitting between real and spiked samples. The proposed methods appeared therefore as a sound alternative in the frame of control (e.g. for post-screening purposes) and/or monitoring surveillance programmes at the target level of 1.0 mg kg(-1) established according to the reported lowest dosage of additive needed to lead a growth promoting effect.
authors.affiliation: European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium. maria-jose.gonzalez-de-la-huebra@ec.europa.eu
authors.forename: María José
authors.initials: MJ
authors.lastname: González de la Huebra
authors.forename: Ursula
authors.initials: U
authors.lastname: Vincent
authors.forename: Christoph
authors.initials: C
authors.lastname: von Holst
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000302:isolation & purification; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D004917:Erythromycin / Q000032:analysis / Q000302:isolation & purification; D015570:Josamycin / Q000032:analysis / Q000302:isolation & purification; D015939:Kitasamycin / Q000032:analysis / Q000302:isolation & purification; D007933:Leucomycins / Q000032:analysis / Q000302:isolation & purification; D018942:Macrolides / Q000032:analysis* / Q000302:isolation & purification; D009827:Oleandomycin / Q000032:analysis / Q000302:isolation & purification; D011200:Poultry; D015572:Spiramycin / Q000032:analysis / Q000302:isolation & purification; D013552:Swine; D013997:Time Factors; D015645:Tylosin / Q000032:analysis / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D007933:Leucomycins; D018942:Macrolides; D015939:Kitasamycin; D004917:Erythromycin; D015572:Spiramycin; C060286:rosaramicin; D015570:Josamycin; D009827:Oleandomycin; D015645:Tylosin