Rapid confirmatory assay for the simultaneous detection of ronidazole, metronidazole and dimetridazole in eggs using liquid chromatography-tandem mass spectrometry

A relatively fast, sensitive and very selective high-performance liquid chromatography-tandem mass spectrometry method for the detection of ronidazole, metronidazole and dimetridazole in eggs has been developed. After a simple extraction with acetonitrile and evaporation of the organic solvent, the extract was filtered and directly injected into the LC-MS-MS system on a C18 column. The abundant parent ions [M + H]+ produced by positive electrospray ionisation were selected for fragmentation with argon. Validation parameters such as detection limit, recovery, linearity and repeatability were determined. The advantage of this method over existing methods is the very simple sample pre-treatment and the high specificity due to the multiple reaction monitoring (MRM) transitions.