Development and Validation of QuEChERS Followed by UHPLC-ToF-MS Method for Determination of Multi-Mycotoxins in Pistachio Nuts

Abstract

Pistachios are one of the types of tree nut fruits with the highest mycotoxin contamination, especially of aflatoxins, worldwide. This study developed a Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method that was followed by Ultra-High Performance Liquid Chromatography combined with Time-of-Flight Mass Spectrometry (UHPLC–ToF-MS) for the determination of mycotoxins in pistachios. Different approaches to dispersive solid phase extraction as a clean-up method for high lipid matrices were evaluated. For this, classic sorbents such as C18 (octadecyl-modified silica) and PSA (primary secondary amine), and new classes of sorbents, namely EMR-Lipid (enhanced matrix removal-lipid) and Z-Sep (modified silica gel with zirconium oxide), were used. The QuEChERS method, followed by Z-Sep d-SPE clean-up, provided the best analytical performance for aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), zearalenone (ZEA), toxin T2 (T2) and toxin HT-2 (HT2) in pistachios. The method was validated in terms of linearity, sensitivity, repeatability, interday precision and recovery; it achieved good results according to criteria imposed by Commission Regulation (EC) no. 401/2006. The method was applied to real samples and the results show that pistachios that are available in Portuguese markets are safe from mycotoxins that are of concern to human health.

Simultaneous Determination of 11 Mycotoxins in Maize via Multiple-Impurity Adsorption Combined with Liquid Chromatography–Tandem Mass Spectrometry

“…Aqueous acetonitrile solutions are often used as extraction solutions to simultaneously detect multiple mycotoxins in existing mycotoxin standards [ 27 , 28 ]. Therefore, we investigated the effects of different acetonitrile-to-water ratios on the extraction of multiple mycotoxins.…”

Developments in mycotoxin analysis: an update for 2021-22

“…In the period since the last review, a few methods for the analysis of mycotoxins with targeted HRMS have been published, which apply well-known QuEChERS-based extraction procedures in combination with clean-up protocols (Mateus et al, 2021, Tsagkaris et al, 2021. For pistachios, a product frequently found in the European Rapid Alert System for Food and Feed due to exceedance of regulatory limits for mycotoxins such as aflatoxins or OTA, Mateus et al (2021) developed a ultra-high pressure liquid chromatography (UHPLC)-HRMS multi-analyte method. To obtain the best signal intensity in MS detection, the authors slightly acidified the suspension of pistachios with formic acid prior to phase separation to improve the extraction of fumonisins into the organic phase.…”

“…Unfortunately, this document with legal relevance within the EU is only occasionally applied by institutions residing within the EU. Mateus et al (2021) have not considered SANTE/12089/2016 identification, but the authors clearly describe their criteria for identifying target compounds based in exact mass, isotope pattern, and retention time which allows experienced readers to evaluate the method's performance. On the other hand, Tsagkaris et al (2021) were able to record two fragment ions per analyte in high resolution, clearly fulfilling the identification criteria of SANTE/12089/2016 but only referred to the document SANTE/12682/2019 which covers a lot more aspects but is dedicated to pesticide analysis (EC, 2019).…”

Quantification, Prevalence, and Pretreatment Methods of Mycotoxins in Groundnuts and Tree Nuts: An Update

“…The second step involves dispersive solid-phase extraction using sorbents like PSA or C 18 to eliminate impurities like fatty acids and sugars. After centrifugation, the supernatant is collected for further analysis with different techniques [41,42,54,72,73].…”

“…To overcome this, researchers introduced enhanced matrix removal-lipid (EMR-lipid) or Z-Sep sorbents, aiming to minimize matrix effects, enhance recoveries, and improve extraction efficiency by removing fats. Mateus et al [73] used a modified QuEChERS method followed by UHPLC-ToF-MS to analyze mycotoxins in pistachio samples. They compared new sorbents (EMR-lipid and Z-Sep) with traditional ones (PSA and C 18 ) in the d-SPE method.…”