Development and validation of a liquid chromatography/tandem mass spectrometric method for the determination of 39 mycotoxins in wheat and maize

Abstract

This paper describes the first validated method for the determination of 39 mycotoxins in wheat and maize using a single extraction step followed by liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (LC/ESI-MS/MS) without the need for any clean-up. The 39 analytes included A- and B-trichothecenes (including deoxynivalenol-3-glucoside), zearalenone and related derivatives, fumonisins, enniatins, ergot alkaloids, ochratoxins, aflatoxins and moniliformin. The large number and the chemical diversity of the analytes required the application of the positive as well as the negative ion ESI mode in two consecutive chromatographic runs of 21 min each. The solvent mixture acetonitrile/water/acetic acid 79 + 20 + 1 (v/v/v) has been determined as the best compromise for the extraction of the analytes from wheat and maize. Raw extracts were diluted 1 + 1 and were injected without any clean-up. Ion-suppression effects due to co-eluting matrix components were negligible in the case of wheat, whereas significant signal suppression for 12 analytes was observed in maize, causing purely proportional systematic errors. Method performance characteristics were determined after spiking blank samples on multiple levels in triplicate. Coefficients of variation of the overall process of <5.1% and <3.0% were obtained for wheat and maize, respectively, from linear calibration data. Limits of detection ranged from 0.03 to 220 microg/kg. Apparent recoveries (including both the recoveries of the extraction step and matrix effects) were within the range of 100 +/- 10% for approximately half of the analytes. In extreme cases the apparent recoveries dropped to about 20%, but this could be compensated for to a large extent by the application of matrix-matched standards to correct for matrix-induced signal suppression, as only a few analytes such as nivalenol and the fumonisins exhibited incomplete extraction. For deoxynivalenol and zearalenone, the trueness of the method was confirmed through the analysis of certified reference materials.

Advanced LC–MS-based methods to study the co-occurrence and metabolization of multiple mycotoxins in cereals and cereal-based food

“…However, despite the use of highly sensitive LC-MS instrumentation, achieving trace detection levels of some analytes in more than 200 multidetection methods is impossible when compromises have to be made with regard to both sample preparation and LC-MS/MS conditions. These methods rely on the injection of raw extracts [43,64], Bdilute and shoot^approaches [36,47], or different modifications of the Bquick, easy, cheap, effective, rugged, and safe^(QuEChERS) approach [48,62,64,65].…”

“…BDilute and shoot^approach BDilute and shoot^and the injection of raw extract, without any cleanup, is now commonly performed in multiresidue LC-MS analysis [47,48,65]. The dilute and shoot LC-MS/MS-based method is considered a pioneering method in the field of multimycotoxin determination [48].…”

“…The dilute and shoot LC-MS/MS-based method is considered a pioneering method in the field of multimycotoxin determination [48]. Simple extraction with a mixture of acetonitrilewater-acetic acid (79:20:1, v/v/v) further diluted 1:1 with acetonitrile-water-acetic acid (20:79:1, v/v/v) was used in the determination of 39 mycotoxins, including conjugated metabolites, in cereals.…”

Determination of the serine palmitoyl transferase inhibitor myriocin by electrospray and Q‐trap mass spectrometry

“…The authors do not report analytically useful information that may facilitate measurement of Myriocin also in other matrices (Shimshoni et al, 2013). Furthermore, Myriocin was never mentioned in earlier articles that describe multi-residue analyses of several tens of fungal metabolites that possibly contaminate grains and wheat (Sulyok et al, 2006;Sulyok et al, 2007aSulyok et al, , 2007b.…”

A Validated UPLC-MS/MS Multi-mycotoxin Method for Nuts and Cereals for the Official Control in Cyprus within the EU Requirements

“…Chromatographic methods commonly used for the quantitative determination of mycotoxins in foodstuffs includes thin layer chromatography (TLC) [16], high performance liquid chromatography (HPLC) coupled with ultraviolet (UV), photo diode array (PDA), fluorescence detectors (FLD) or mass spectrometry (MS), and gas chromatography (GC) coupled with electron capture (ECD), flame ionization (FID) or MS detectors [17]. Due to the high toxicity and occurrence of mycotoxins, rapid and reliable screening methods need to be developed for their identification and quantification in foodstuff in order to ensure safety and compliance with the legislation.…”