Simultaneous determination of six major ergot alkaloids and their epimers in cereals and foodstuffs by LC–MS–MS

Abstract

This paper describes a new and rapid method for accurate quantification of the six ergot alkaloids, ergometrine, ergotamine, ergosine, ergocristine, ergocryptine, and ergocornine, by liquid chromatography-tandem mass spectrometry (LC-MS-MS). The six ergot alkaloids studied have been defined by the European Food Safety Authority (EFSA) as among the most common and physiologically active ones. In addition, the method enables the quantification of the corresponding six epimers (ergo-inines) of these ergot alkaloids. This is of considerable importance in terms of the differences in toxicity of the isomeric forms. The method involves extraction under alkaline conditions using a mixture of acetonitrile and ammonium carbonate buffer followed by a rapid clean-up using dispersive solid-phase extraction with PSA (primary secondary amine) and a short chromatographic LC-run (21 min) with subsequent MS-MS detection. The method was developed and validated using ten different cereal and food samples. The major strength of the new method compared with previously published techniques is the simplicity of the clean-up procedure and the short analysis time. The limits of quantification were 0.17 to 2.78 μg kg(-1) depending on the analyte and matrix. Recovery values for the 12 ergot alkaloids spiked into ten different matrices at levels of 5, 50, and 100 μg kg(-1) were between 69 and 105% for 85 of 90 recovery measurements made over six days. Measurement uncertainty values were highly satisfactory. At a concentration level of 5 μg kg(-1) the expanded measurement uncertainty ranged from ±0.56 to ±1.49 μg kg(-1), at a concentration level of 100 μg kg(-1) the expanded measurement uncertainty ranged from ±8.9 to ±20 μg kg(-1). Both LOQs and measurement uncertainties were dependent on the analyte but almost independent of the matrix. The method performance was satisfactory when tested in a mini-intercomparison study between three laboratories from three different countries.

Effects of the level of feed intake and ergot contaminated concentrate on ergot alkaloid metabolism and carry over into milk

“…Therefore, future studies should use analytical methods characterised by lower LOQs than those of the present experiment. For example, by using a LC-MS-MS method the LOQs varied between 0.17 and 2.78 lg/kg depending on matrix and alkaloid species [32] and are l2 -59-fold lower than those of the present experiment.…”

Development and validation of a new LC–MS/MS method for the simultaneous determination of six major ergot alkaloids and their corresponding epimers. Application to some food and feed commodities

“…It is therefore important to consider both epimers when the ergot alkaloid contamination level of a cereal or cereal product has to be determined. Different methods have been reported for the analysis of ergot alkaloids, including thin layer chromatography (TLC) (Salvat & Godoy, 2001), capillary electrophoresis (CE) (Franch & Blaschke, 1998), enzyme linked immunosorbent assay (ELISA) (Hill et al, 2001), gas chromatography (GC) with electron capture detection (ECD) (Barrow & Quigley, 1975), liquid chromatography (LC) with ultraviolet (Veress, 1993), fluorescence (Komarova & Tolkachev, 2001;Storm et al, 2008) or mass spectrometric (MS) (Burk et al, 2006;Kokkonen & Jestoi, 2010;Krska, Stubbings, Macarthur, & Crews, 2008;Mohamed, Gremaud, Rychoz-Payot, Tabet, & Guy, 2006) detection. In recent years, LC-MS has become the method of choice for mycotoxin determination (Shephard et al, 2011;Spanjer, 2010), and has provided an unequivocal identification of ergot alkaloids in various matrices (Friedrich et al, 2004;Lehner, Craig, Fannin, Bush, & Tobin, 2005;Mohamed et al, 2006).…”

Degradation and epimerization of ergot alkaloids after baking and in vitro digestion

“…Therefore, both epimers have to be taken into consideration in sample analysis, making epimer-specific analytical techniques very important. The epimerization rate differs for each EA and is dependent on the temperature [8], the solvent, and pH [9,10]. Therefore, a proper sample isolation protocol is crucial in allowing the measurement without further isomerization during sample preparation.…”