Development of a liquid chromatography-tandem mass spectrometry with pressurized liquid extraction method for the determination of benzimidazole residues in edible tissues

A confirmatory and quantitative method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) combined with a pressure liquid extraction (PLE) was developed for the determination of 11 benzimidazole and 10 metabolites of albendazole, fenbendazole and mebendazole in the muscles and livers of swine, cattle, sheep and chicken. For sample preparation, we used an automated technique of PLE method. The optimum extraction conditions were obtained using an 11 ml Accelerated Solvent Extraction (ASE) cells, acetonitrile/hexane as the extraction solvent. HPLC analysis was performed on a C18 column with gradient elution using acetonitrile and 5 mmol l(-1) formic ammonium as mobile phase. The analytes were detected in the positive ion multiple reaction monitoring (MRM) mode by the LC-ESI-MS/MS analysis. The recoveries of benzimidazole (BZDs) spiked at the levels of 0.5 mu g kg(-1) ranged from 70.1% to 92.7%; the between-day relative standard deviations were no more than 10%. The limits of quantification were 0.02-0.5 mu g kg(-1). The optimized method was successfully applied to monitor real samples containing BZDs, demonstrating the method to be simple, fast, robust and suitable for identification and quantification of BZDs residues in animal products. (C) 2011 Elsevier B.V. All rights reserved