Search results for "QUECHERS"
showing 10 items of 53 documents
Augstas izšķirtspējas masspektrometrijas pielietojums pesticīdu nemērķētam skrīningam pārtikas produktos
2019
Augstas izšķirtspējas masspektrometrijas pielietojums pesticīdu nemērķētam skrīningam pārtikas produktos, Vasiļjeva V., zinātniskais vadītājs Mg. chem. Ruško J., Bakalaura darbs, 40 lappuses, 8 attēli, 8 tabulas, 44 literatūras avoti, 3 pielikumi. Latviešu valodā. Pesticīdi plaši mūsdienās tiek izmantoti lauksaimniecībā, jo augu kaitēkļi, tādi kā nezāles, slimības u.c. ir spējīgi samazināt lielu procentuālo daļu no visām lauksaimniecības kultūru ražām pasaulē. Pesticīdu toksiskuma dēļ bioķīmiskie procesi dzīvās šūnās mainās, tie nelabvēlīgi ietekmē cilvēka veselību. Lai pasargātu cilvēkus no nelabvēlīgām sekām, pasaulē tiek plaši izstrādātas daudzas noteikšanas metodes dažāda veida augos un…
Analysis of mycotoxins in barley using ultra high liquid chromatography high resolution mass spectrometry: comparison of efficiency and efficacy of d…
2012
The effectiveness of four extraction methods (modified QuEChERS, matrix solid-phase dispersion (MSPD), solid-liquid extraction (SLE) and solid-phase extraction (SPE) clean-up) were evaluated for simultaneous determination of 32 mycotoxins produced by the genus Fusarium, Claviceps, Aspergillus, Penicillium and Alternaria in barley by ultra high pressure liquid chromatography coupled to ultra-high resolution mass spectrometry (UHPLC-Orbitrap(®) MS). The efficiency and efficacy of extraction methods were evaluated and compared in number of extracted mycotoxins and obtained recoveries. From the one point of view, QuEChERS procedure was fast and easy, as well as it was able to successfully extra…
Sensitive Monoclonal Antibody-Based Immunoassays for Kresoxim-methyl Analysis in QuEChERS-Based Food Extracts
2014
Kresoxim-methyl is nowadays widely used to combat a diversity of common diseases affecting high-value crops. In this article, we report the development and characterization of two novel immunoassays for the analysis of this pioneer strobilurin fungicide, and for the first time, a validation study with food samples was performed. A direct and an indirect competitive immunoassay based on a new anti-kresoxim-methyl monoclonal antibody were developed for sensitive and specific chemical analysis. Optimized assays showed limits of detection of 0.1 μg/L. Fruit and vegetable samples were extracted with acetonitrile by the QuEChERS procedure and analyzed by the developed immunoassays after a simple …
Pesticides and Herbicides: Residue Determination
2016
Pesticide and herbicide residue determination in food is becoming an especially imperative and challenging issue. Commonly, it involves the simultaneous trace analysis of hundreds of compounds belonging to many chemical classes. This article provides a review of the current status of the routine methods in the monitoring and control of these residues and discusses the analytic problems arising at each stage of the procedure. The role of mass spectrometry in screening, identification, and confirmation of target and nontarget pesticides is highlighted. Consideration is given to new developments and future trends.
Evaluation of mycotoxins and their metabolites in human breast milk using liquid chromatography coupled to high resolution mass spectrometry
2014
Humans can be exposed to mycotoxins through the food chain. Mycotoxins are mainly found as contaminants in food and could be subsequently excreted via biological fluids such as urine or human breast milk in native or metabolised form. Since breast milk is usually supposed as the only food for new-borns, the occurrence of mycotoxins in thirty-five human milk samples was evaluated by a newly developed method based on QuEChERS extraction and UHPLC-HRMS detection. The method described here allows the detection of target mycotoxins in order to determine the quality of this initial feeding. The method has been fully validated, with recoveries ranging from 64% to 93% and relative standard deviatio…
Determination of organic pollutants in Anguilla anguilla by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS)
2021
© 2021 The Authors.
Pesticide analysis in coffee leaves using a quick, easy, cheap, effective, rugged and safe approach and liquid chromatography tandem mass spectrometr…
2017
An analytical method using a quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure for multi-residue determination of 52 pesticides in coffee leaf extractshas been developed and validated according to SANTE/11945/2015 guidelines. Different sorbent combinations for dispersive solid phase extraction (d-SPE) clean-up as well as dispersive liquid-liquid microextraction (DLLME) were tested. The relative standard deviations (RSDs) for the recovery of 87-94% of pesticides added to coffee leaf extracts,was ≤20% for samples spiked at concentrations up to 50ng*g-1 depending on the clean-up procedures. However, samples spiked with a 100ng*g-1 pesticide mixture gave RSDs>20% for most pest…
Multi-mycotoxin determination in barley and derived products from Tunisia and estimation of their dietary intake.
2017
A study on raw barley and derived products (barley soup and beers) was carried out to determine the natural presence of twenty-four mycotoxins by both liquid chromatography and gas chromatography coupled to tandem mass spectrometry (MS/MS). The developed multi-mycotoxin procedure was based on both SLE and QuEChERS extraction steps. 66% of analyzed samples presented mycotoxin contamination and only one sample, which was soup of barley (6 ng/g), exceeded the maximum level (ML) established by EU for OTA (5 ng/g). Raw barley was the most contaminated matrix (62%), which concentrations ranged from 1.70 to 287.13 ng/g) and type of detected mycotoxins (DON, 15AcDON, NEO, NIV, HT2, FB1, OTA, ENA, E…
Alternaria Mycotoxins in Food and Feed: An Overview
2017
Alternariais one of the major mycotoxigenic fungal genera with more than 70 reported metabolites.Alternariamycotoxins showed notably toxicity, such as mutagenicity, carcinogenicity, induction of DNA strand break, sphingolipid metabolism disruption, or inhibition of enzymes activity and photophosphorylation. This review reports on the toxicity, stability, metabolism, current analytical methods, and prevalence ofAlternariamycotoxins in food and feed through the most recent published research. Half of the publications were focused on fruits, vegetables, and derived products—mainly tomato and apples—while cereals and cereal by-products represented 38%. The most studied compounds were alternario…
Contaminants of emerging concern in the environment. Turia River as study case
2018
Tesis llevada a cabo para conseguir el grado de Doctor por la Universidad de Valencia.--2018-04-05