Table of Contents
Chromatography Research International
Volume 2012 (2012), Article ID 135854, 9 pages
Research Article

Ion Suppression Study for Tetracyclines in Feed

1Departament de Química Analítica, Facultat de Química, Universitat de Barcelona, c/Martí i Franquès 1, 08028 Barcelona, Spain
2RIKILT-Institute of Food Safety, Wageningen University and Research Center, Akkermaalsbos 2, 6708 WB, P.O. Box 230, 6700AE Wageningen, The Netherlands

Received 13 June 2012; Accepted 8 August 2012

Academic Editor: Andrew Cannavan

Copyright © 2012 Joaquim Chico et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Ion suppression in analysis of tetracyclines in feed was studied. The conventional analysis consists of a liquid extraction followed by a clean-up step using solid phase extraction (SPE) technique and analysis of the tetracyclines by liquid chromatography and mass spectrometric detection. Various strategies for extraction and cleanup were tested in the present work, and the effectiveness to decrease the ion suppression on the MS/MS signals was evaluated. Four sample treatment methods were tested with five different feed samples. Extraction solvents tested were McIlvaine buffer and a mixture of McIlvaine buffer dichloromethane (3 : 1). SPE cartridges for cleanup were Oasis HLB, Oasis MCX, and Oasis MAX. The effectiveness of the methods was evaluated in terms of decreasing the ion suppression effect but also of decreasing the variability of ion suppression between samples. The method that provided the most satisfactory results involved a clean-up step based on SPE using mixed-mode cation exchange cartridges (Oasis MCX).