Comment on Sinkovič et al. Isotope Fingerprints of Common and Tartary Buckwheat Grains and Milling Fractions: A Preliminary Study. Foods 2022, 11, 1414

We read with interest the publication by Sinkovic et al. [...

Geographical Differentiation of Hom Mali Rice Cultivated in Different Regions of Thailand Using FTIR-ATR and NIR Spectroscopy

Although Hom Mali rice is considered the highest quality rice in Thailand, it is susceptible to adulteration and substitution. There is a need for rapid, low-cost and efficient analytical techniques for monitoring the authenticity and geographical origin of Thai Hom Mali rice. In this study, two infrared spectroscopy techniques, Fourier-transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) and near-infrared (NIR) spectroscopy, were applied and compared for the differentiation of Thai Hom Mali rice from two geographical regions over two production years. The Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) model, built using spectral data from the benchtop FTIR-ATR, achieved 96.97% and 100% correct classification of the test dataset for each of the production years, respectively. The OPLS-DA model, built using spectral data from the portable handheld NIR, achieved 84.85% and 86.96% correct classification of the test dataset for each of the production years, respectively. Direct NIR analysis of the polished rice grains (i.e., no sample preparation) was determined as reliable for analysis of ground rice samples. FTIR-ATR and NIR spectroscopic analysis both have significant potential as screening tools for the rapid detection of fraud issues related to the geographical origin of Thai Hom Mali rice

Development of a liquid chromatography-tandem mass spectrometric method for the simultaneous determination of tropane alkaloids and glycoalkaloids in crops

International audienceA new, rapid and sensitive multiresidue method is reported for the simultaneous determination of tropane alkaloids (tropine, atropine, scopolamine, homatropine, anisodamine) and glycoalkaloids (α-solanine, α-chaconine) in grains and seeds (wheat, rye, maize, soybean, linseed). Dispersive solid phase extraction (DSPE) was performed with 0.5% formic acid in acetonitrile/water and a mixture of magnesium sulphate, sodium chloride and sodium citrate. For a fast and effective clean-up procedure for oily matrices such as soybean and linseed, matrix solid phase dispersion (MSPD) C18 material was used to remove co-extracted non-polar components. No clean-up was necessary for less oily matrices following extraction. The analytes were separated by isocratic HPLC on a Chirobiotic V column and detected using a triple quadrupole mass spectrometer with electrospray ionization (ESI). All analytes were monitored in the positive ion mode. The method performance is presented in terms of linearity in the range 5-80 ng/g (r2=0.998), specifity, selectivity, accuracy (recoveries from 61-111%), precision (CV < 5%) and ruggedness. The limits of quantitation (LOQ) were in the range 2.2-4.9 ng/g

Ruggedness testing of an analytical method for pesticide residues in potato

© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. The best demonstration of the ruggedness of a method is monitoring its performance on an ongoing basis as part of the analytical quality control applied in the laboratory. However, an initial demonstration of the ruggedness is often performed as one aspect of the method validation, to give confidence that the method should perform well under normal variations in conditions in routine application. This initial ruggedness testing is typically performed using either multiple replicate analyses or application of design of experiments (DoEs) which minimizes the number of analyses, time and effort required to detect influences on the measurement results. Two DoEs were applied for ruggedness testing for a modified QuEChERS multiresidue method for the detection of pesticide residues in potato by GC–MS/MS. Seven experimental factors were studied using an eight-run Plackett–Burman design replicated three times and an augmented definitive screening design with 34 runs. The relative effectiveness of the two approaches is discussed, in terms of their statistical significance, their cost-effectiveness and the richness of information they provide on the effects of the parameters investigated and the actual robustness of the method being tested.status: publishe

Multi-class determination of anthelmintics in soil and water by LC-MS/MS

<div><p>The translocation of antiparasitic drugs from animal excrement through soil and water to crops and forages and their recycling to food-producing animals is a potential concern with respect to the contamination of the food chain. To facilitate the investigation of this problem, an LC-MS/MS method for selected anthelmintics in soil and water was developed. The soil sample preparation involved a simple solvent extraction and dispersive clean-up technique. The method was validated at 10, 20 and 40 µg kg⁻¹ for levamisole, fenbendazole, fenbendazole sulphoxide and fenbendazole sulphone and at 20, 40 and 80 µg kg⁻¹ for eprinomectin. LOQs were 10 µg kg⁻¹ for the first four compounds and 20 µg kg⁻¹ for eprinomectin. The overall mean recoveries ranged from 76.1% to 89% for loamy soils and from 79.9% to 96.9% for sandy soils. Analysis of water samples was performed by extraction/concentration on an Oasis-HLB (Aschaffenburg, Germany) cartridge. Validation was performed at 0.25, 0.5 and 1.0 µg l⁻¹. The LOQ for all compounds was 0.25 µg l⁻¹. Method recovery (and RSD) varied between 35.4% (28) for eprinomectin and 125.1% (16) for fenbendazole sulphone. The validated methods were applied to soil and water samples in a study on the behaviour of anthelmintic drugs in a soil-plant-water system (manuscript on “transport investigation of antiparasitic drugs based on a lysimeter experiment” in preparation).</p></div

Validation of an Analytical Method for the Determination of Pesticide Residues in Vine Leaves by GC-MS/MS

A modified and miniaturized SweEt/QuEChERS method for pesticide residue analysis applied to vine leaves is presented. The deep-frozen plant material was cryogenically processed. A 2 g analytical portion was hydrated for 30 min and extracted with acidified ethyl acetate after buffering with NaHCO₃ and adding Na₂SO₄. A dispersive solid-phase (d-SPE) cleanup step with primary–secondary amine (PSA) was performed. The pesticide residues were determined using GC-MS/MS. The whole procedure was validated for 54–59 pesticides at 0.01, 0.02, 0.1, and 0.2 mg/kg in fresh vine leaves (<i>Vitis vinifera</i>). The key method performance parameters investigated were specificity, linearity, trueness, within laboratory repeatability and reproducibility, limit of detection, limit of quantitation, and matrix effects. Recoveries for the 59 pesticides tested ranged from 60 to 110%, and the RSDs were lower than 20% for the majority of the pesticides studied