Determination of deoxynivalenol in cereals by immunoaffinity clean-up and ultra-high performance liquid chromatography tandem mass spectrometry

Immunoaffinity Cleanup and Isotope Dilution-Based Liquid Chromatography Tandem Mass Spectrometry for the Determination of Six Major Mycotoxins in Feed and Feedstuff

In this study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of deoxynivalenol, aflatoxin B₁, zearalenone, ochratoxin A, T-2 toxin and fumonisin B₁ in feed and feedstuff was established. The sample was extracted with an acetonitrile–water mixture (60:40, v/v), purified by an immunoaffinity column, eluted with a methanol–acetic acid mixture (98:2, v/v), and reconstituted with a methanol–water mixture (50:50, v/v) after drying with nitrogen. Finally, the reconstituted solution was detected by LC-MS/MS and quantified by isotope internal standard method. The six mycotoxins had a good linear relationship in a certain concentration range, the correlation coefficients were all greater than 0.99, the limits of detection were between 0.075 and 1.5 µg·kg⁻¹, and the limits of quantification were between 0.5 and 5 µg·kg⁻¹. The average spike recoveries in the four feed matrices ranged from 84.2% to 117.1% with relative standard deviations less than 11.6%. Thirty-six actual feed samples were analyzed for mycotoxins, and at least one mycotoxin was detected in each sample. The proposed method is reliable and suitable for detecting common mycotoxins in feed samples.

Immunoaffinity Extraction and Alternative Approaches for the Analysis of Toxins in Environmental, Food or Biological Matrices

The evolution of instrumentation in terms of separation and detection allowed a real improvement of the sensitivity and analysis time. However, the analysis of ultra-traces of toxins in complex samples requires often a step of purification and even preconcentration before their chromatographic analysis. Therefore, immunoaffinity sorbents based on specific antibodies thus providing a molecular recognition mechanism appear as powerful tools for the selective extraction of a target molecule and its structural analogs to obtain more reliable and sensitive quantitative analysis in environmental, food or biological matrices. This review focuses on immunosorbents that have proven their efficiency in selectively extracting various types of toxins of various sizes (from small mycotoxins to large proteins) and physicochemical properties. Immunosorbents are now commercially available, and their use has been validated for numerous applications. The wide variety of samples to be analyzed, as well as extraction conditions and their impact on extraction yields, is discussed. In addition, their potential for purification and thus suppression of matrix effects, responsible for quantification problems especially in mass spectrometry, is presented. Due to their similar properties, molecularly imprinted polymers and aptamer-based sorbents that appear to be an interesting alternative to antibodies are also briefly addressed by comparing their potential with that of immunosorbents.

Multiple antibodied based immunoaffinity columns preparation for the simultaneous analysis of deoxynivalenol and T-2 toxin in cereals by liquid chromatography tandem mass spectrometry

Deoxynivalenol (DON) and T-2 toxin are major trichothecenes contaminated in cereals, which might bring harmful effects to humans. In this research, mixed anti-DON and anti-T-2 mAb were used for multiple immunoaffinity columns (mIACs) preparation. Under the optimal conditions, column capacities were tested at 1280 ng/mL for DON and 1160 ng/mL for T-2 toxin. Regeneration investigation showed mIACs capacities were over 510 ng/mL for DON and 440 ng/mL for T-2 toxin in 10 recycle usages. Good performances were obtained when applying mIACs purification coupled UHPLC-MS/MS for spiked samples with limit of detection at 3-13 μg/kg and mean recoveries at 79.0-97.6%. Applying to estimate the exposure of DON and T-2 toxin in commercial samples, maize samples were 100% DON positive and rice samples were 40% DON positive while T-2 toxin was negative in all tested samples. The proposed method is reliable and suitable for monitoring DON and T-2 toxin in cereal samples.

Mycotoxins Contaminant in Kelp: A Neglected Dietary Exposure Pathway

In order to investigated current occurrence of major mycotoxins in dietary kelp in Shandong Province in Northern China, a reliable, sensitive, and rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated for simultaneous determination of the 7 most frequent mycotoxins, including 3-acetoxy deoxynivalenol (3AcDON), 15-acetoxy deoxynivalenol (15AcDON), Deoxynivalenol (DON), Fusarenon-X (F-X), Nivalenol (NIV), T-2 toxin (T-2), and Zearalenone (ZEA). Based on optimized pretreatment and chromatographic and mass spectrometry conditions, these target analytes could be monitored with mean recoveries from 72.59~107.34%, with intra⁻day RSD < 9.21%, inter⁻day RSD < 9.09%, LOD < 5.55 μg kg-1, and LOQ < 18.5 μg kg-1. Approximately 43 kelp samples were detected, 3AcDON/15AcDON ranged from 15.3 to 162.5 μg kg-1 with positive rate of 86% in Shandong Province in Northern China. Considering there were no related investigations about mycotoxin contamination in kelp, the high contamination rate of 3AcDON/15AcDON in kelp showed a neglected mycotoxin exposure pathway, which might lead to high dietary exposure risk to consumers.

Protein expression of sensory and motor nerves: Two-dimensional gel electrophoresis and mass spectrometry

The present study utilized samples from bilateral motor branches of the femoral nerve, as well as saphenous nerves, ventral roots, and dorsal roots of the spinal cord, to detect differential protein expression using two-dimensional gel electrophoresis and nano ultra-high performance liquid chromatography electrospray ionization mass spectrometry tandem mass spectrometry techniques. A mass spectrum was identified using the Mascot search. Results revealed differential expression of 11 proteins, including transgelin, Ig kappa chain precursor, plasma glutathione peroxidase precursor, an unnamed protein product (gi|55628), glyceraldehyde-3-phosphate dehydrogenase-like protein, lactoylglutathione lyase, adenylate kinase isozyme 1, two unnamed proteins products (gi|55628 and gi|1334163), and poly(rC)-binding protein 1 in motor and sensory nerves. Results suggested that these proteins played roles in specific nerve regeneration following peripheral nerve injury and served as specific markers for motor and sensory nerves.

Development of a liquid chromatography-tandem mass spectrometry with ultrasound-assisted extraction and auto solid-phase clean-up method for the determination of Fusarium toxins in animal derived foods

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the simultaneous determination of 19 Fusarium toxins and their metabolites including deoxynivalenol (DON), nivalenol (NIV), T-2 toxin (T-2), HT-2 toxin (HT-2), 3-acetyldeoxynivalenol (3-AcDON), 15-acetyldeoxynivalenol (15-AcDON), neosolaniol (NEO), fusarenon-X (F-X), diacetoxyscirpenol (DAS), monoacetoxyscirpenol (MAS), zearalanone (ZAN), zearalenone (ZON), α-Zearalenol (α-ZOL), β-Zearalenol (β-ZOL), a-Zearalanol (α-ZAL), β-Zearalanol (β-ZAL), T-2 triol, T-2 tetraol, deepoxy-deoxynialenol (DOM-1) in the muscle, liver, kidney, fat of swine, bovine and sheep, muscle and liver of chicken, muscle and skin of fish, as well as milk and eggs. Sample preparation procedure includes ultrasound-assisted extraction with acetonitrile/water (90/10, v/v), defatting with n-hexane and final clean-up with auto solid phase extraction (SPE) on Bond Elut Mycotoxin cartridges. The detection and quantification of the analytes were performed by a reversed-phase liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (LC/ESI-MS/MS). DON, NIV, DOM-1, 3-AcDON, 15-AcDON, F-X, ZON, ZAN, α-ZOL, β-ZOL, α-ZAL, β-ZAL, T-2 triol and T-2 tetraol were detected in a negative ion mode, while T-2 toxin, HT-2 toxin, NEO, DAS and MAS were detected in a positive ion mode. The CCα and CCβ of the analytes in different samples varied from 0.16 to 1.37μg/kg and 0.33 to 2.34μg/kg, respectively. The recoveries of spiked sample from 0.5μg/kg to 8μg/kg ranged from 64.8% to 108.2% with the relative standard deviations of less than 19.4%. Performances of the whole analytical procedure meet the criteria established by the European Commission for mass spectrometric detection.

Developments in mycotoxin analysis: an update for 2011-2012

This review highlights developments in mycotoxin analysis and sampling over a period between mid-2011 and mid- 2012. It covers the major mycotoxins aflatoxins, Alternaria toxins, ergot alkaloids, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. A section on mycotoxins in botanicals and spices is also included. Methods for mycotoxin determination continue to be developed using a wide range of analytical systems ranging from rapid immunochemical-based methods to the latest advances in mass spectrometry. This review follows the format of previous reviews in this series (i.e. sections on individual mycotoxins), but due to the rapid spread and developments in the field of multimycotoxin methods by liquid chromatography-tandem mass spectrometry, a separate section has been devoted to advances in this area of research.