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Oznaczanie pozostałości pestycydów w próbkach żywności w wykorzystaniem metodyki QuEChERS = QuEChERS approach for the determination of pesticide residues in food matrixes
PublikacjaBez wątpienia, wartym uwagi podejściem do problemu oznaczania pestycydów, ze względu na różnorodność tej grupy związków, jest zastosowanie metodyk oznaczania pozostałości (multi-residue methods - MRMs). Niestety, w literaturze naukowej można znaleźć stosunkowo niewiele informacji na temat takiego podejścia do oznaczania pozostałości pestycydów w próbkach żywności. Stąd próba przybliżenia czytelnikom kilku najistotniejszych, zdaniem...
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QuEChERS - szybkość i łatwość w przygotowaniu próbek
PublikacjaSkomplikowany skład matrycy oraz śladowe poziomy oznaczanych składników stanowiły główny problem przy oznaczaniu związków organicznych w produktach żywności. Na przestrzeni lat opracowano wiele technik przygotowania próbek stałych jednak większość z nich zużywa duże ilości rozpuszczalników, są czasochłonne, kosztowne oraz do przeprowadzenia potrzebują wykwalifikowanego personelu.Potrzeba prostej, taniej techniki, którą można zastosować...
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Determination of norflurazon concentration in wheat leaves using a modified QuEChERS method
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublikacjaThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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Determination of pesticide residues in fruits and vegetables using QuEChERS sample preparation method
PublikacjaThe intensive development of agriculture means that more and more toxic organic and inorganic compounds are entering the environment. Because of their widespread use, environmental stability, selective toxicity and bioaccumulative capability, pesticides belong to the most hazardous substances contaminating the environment. They are particularly dangerous in fruits and vegetables, because they are one of the reasons why people are...
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Multiresidue Methods for Determination of Currently Used Pesticides in Fruits and Vegetables Using QuECHERS Technique
PublikacjaApplied all over the world, pesticides are some of the most common pollutants of the environment because of their stability, mobility, their consequent long-term adverse effects on living organisms in general and human health in particular. For these reasons it is essential to monitor and analyse pesticide residues in the fruits and vegetables. The analysis of food samples for the presence of pesticides causes a lot of difficulties...
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Challenges in determination of pesticides from various chemical groups in fruits and vegetables applying QuEChERS method
PublikacjaPesticides are a large group of compounds with different physical and chemical properties, which place some of them among the most toxic, environmentally stable, and mobile substances. Nevertheless, their number, use, and application are continuously expanding. A consequence of their use is the possible presence of residues in treated food products. To protect consumers from exposure to unacceptable levels of pesticides Maximum...
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Analysis of pesticide residues in fruits and vegetables using QuEChERS sample preparation method and gas chromatography with electron capture detection
PublikacjaPesticides are a numerous and diverse group of chemical compounds. They are some of the most toxic substances contaminating the environment, which are used to eliminate pests in agriculture and the household. Despite considerable progress in the development of methods for preparing samples for analysis and for the final determination of analytes, the analysis of pesticides in biological samples continues to present challenges to...
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Determination of Pesticide Residues in Honeybees using Modified QUEChERS Sample Work-Up and Liquid Chromatography-Tandem Mass Spectrometry
PublikacjaIncreasing emissions of chemical compounds to the environment, especially of pesticides, is one of factors that may explain present honeybee colony losses. In this work, an analytical method employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimized for the simultaneous screening of 19 pesticides which have not been yet determined in honeybee samples from northern Poland (Pomerania). The sample preparation,...
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Analysis of pesticide residue in tomato samples using analytical protocol based on application of QuEChERS technique and GC-ECD system
PublikacjaQuEChERS sample preparation method was used for the determination of 10 pesticides and their metabolites in tomato samples, coupled to gas chromatography with electron capture detector (GCECD). The experimental parameters including oven temperature program, amount of the sample and purifying agent were optimized. The GC-ECD method was validated in terms of linearity, selectivity and recovery. The limits of detection (LODs) of the...
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Analysis of pesticide residue in fruits and vegetables using analytical analytical protocol based on application of QuEChERS technique and GC-ECD system
PublikacjaQuEChERS sample preparation method was used for the determination of 10 pesticides and their metabolites in fruits (apple, grape) and vegetables (tomato, paprika), coupled to gas chromatography with electron capture detector (GC-ECD). The experimental parameters including amount of the sample, types of solvents, extraction time and types of sorbent at the purification stage were optimized. The GC-ECD method was validated in terms...
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Determination of pesticide residues in food matrices using the QuEChERSmethodology
PublikacjaOznaczanie pozostałości pestycydów w próbkach żywności jest ogromnym wyzwaniem głównie z powodu dużych ilości substancji przeszkadzających, które podlegają ekstrakcji razem z analitami i najczęściej wywierają negatywny wpływ na tok analizy. Z drugiej strony, zapewnienie "bezpieczeństwa żywności" wymaga monitorowania w niej pozostałości pestycydów. W artykule przedstawiono nowe podejście do oznaczania pozostałości pestycydów w próbkach...
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Comparison of Two Methods for the Determination of Selected Pesticides in Honey and Honeybee Samples
PublikacjaDeveloped and validated analytical methods for the determination of a wide spectrum of pesticide residues in honey and honeybee samples after the modification of QuEChERS extraction in combination with gas chromatography–tandem quadrupole mass spectrometry (GC-MS/MS) and liquid chromatography–tandem quadrupole mass spectrometry (LC-MS/MS) were discussed and compared. The developed methods were evaluated regarding the utilized equipment...
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Pesticide residues levels in honey from apiaries located of Northern Poland
PublikacjaConcentration levels of 30 pesticide residues were measured in honey samples collected from apiaries in northern part of Poland (Pomerania) using method based on the QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry with electron spray ionization (LC-ESI-MS/MS). In 29% of the samples were found positive for at least some of the target compounds. Concentration of bifenthrin, fenpyroximate, methidathion,...
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Development of gas chromatography - tandem mass spectrometry procedure for development of pesticide residues in honey and honeybee samples
PublikacjaA new analytical procedure of determination of multiresidue of pesticides based on application of the modified QuEChERS approach at the step of sample preparation and technique GC-MS/MS has been developed and applied for studies the real honey and honeybee samples. Samples were collected from northern Poland (Pomerania). The proposed procedure enables for the determination of 34 and 30 pesticides residues respectively on honey...
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Properties and determination of pesticides in fruits and vegetables
PublikacjaThe intensive development of agriculture means that more and more toxic organic and inorganic compounds are entering theenvironment. Because of their widespread use, stability, selective toxicity and bioaccumulation, pesticides are among the mosttoxic substances contaminating the environment. They are particularly dangerous in fruit and vegetables, by which people areexposed to them. It is therefore crucial to monitor pesticide...
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Determining pesticide contamination in honey by LC-ESI-MS/MS - Comparison of pesticide recoveries of two liquid-liquid extraction based approaches
PublikacjaHoney, a valuable food product, may be contaminated by xenobiotics during its production and/or harvest. The determination of trace levels of contaminants in a complex matrix like honey still presents a challenge to analytical chemists. The aim of this work was to assess and compare the extraction efficiencies of 30 pesticide residues (acaricides, insecticides, herbicides, fungicides), belonging to over 15 different chemical classes....
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Development of a liquid chromatography–tandem mass spectrometryprocedure for determination of endocrine disrupting compounds infish from Mediterranean rivers
PublikacjaA new, sensitive and rapid method based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe)approach followed by ultra high performance liquid chromatography coupled with tandem mass spec-trometry (UHPLC–MS/MS) was developed for the determination of nineteen endocrine disruptors (EDCs)and related compounds belonging to different classes in various fish species. Matrix effect on the analyti-cal performance was evaluated,...
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Determination of Pesticide Residues in Honey using the GC×GC-TOFMS Technique
PublikacjaIn this study, a QuEChERS method and gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOFMS) was developed for rapid extraction and simultaneous determination of 12 pesticide residues in honey. The GCxGC-TOFMS method was validated according to the SANCO guidance in terms of linearity, selectivity, reproducibility and recovery. Regarding the results, recovery rates ranged between 70-120% with relative standard...
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Ekstrakcja do fazy stałej niejedno ma imię
PublikacjaW czasach, gdy we wszystkich przejawach aktywności człowieka trzeba się odnieść do przesłanek leżących u podstaw zrównoważonego rozwoju trudno jest uzasadnić stosowanie w praktyce analitycznej takich procedur i operacji, które pociągają za sobą konieczność:użycia dużych ilości rozpuszczalników i odczynników chemicznychdużych nakładów energii czy też przyczyniają się do wzrostu ekspozycji pracowników laboratoriów na niekorzystne...
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New Trends in Sample Preparation Techniques for the Analysis of the Residues of Pharmaceuticals in Environmental Samples
PublikacjaPharmaceutical residues in the environment is a field of special interest due to the adverse effects to either human health or aquatic and soil environment. Pharmaceuticals have been already detected in underground, surface and wastewaters, soils, manure and sediments. The growing awareness of environmental pollution arising from human activity forces the need for their comprehensive determination. Environmental samples are complex...
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Recent advancements in LC‐MS based analysis of biotoxins: Present and future challenges
PublikacjaThere has been a rising concern regarding the harmful impact of biotoxins, source of origin, and the determination of the specific type of toxin. With numerous reports on their extensive spread, biotoxins pose a critical challenge to figure out their parent groups, metabolites, and concentration. In that aspect, liquid chromatography‐mass spectrometry (LC‐MS) based analysis paves the way for its accurate identification and quantification....
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OZNACZANIE POZOSTAŁOŚCI PESTYCYDÓW W ORGANIZMACH PSZCZELICH ORAZ W MIODZIE Z WYKORZYSTANIEM PROCEDURY OPARTEJ NA ZASTOSOWANIU CHROMATOGRAFÓW SPRZĘŻONYCH Z TANDEMOWYMI SPEKTROMETRAMI MAS (GC-MS/MS i LC-MS/MS)
PublikacjaPestycydy to bardzo liczna grupa różnorodnych związków chemicznych stosowa-nych w rolnictwie. Ze względu na swoją trwałość gromadzą się w różnych elementach środowiska i mogą występować w obszarze, na którym nigdy nie zostały użyte. Zachodzi także proces ich bioakumulacji w tkankach oraz narządach zwierząt i roślin. Stosowane w rolnictwie środki ochrony roślin (szczególnie w okresie wzmożonych zabiegów agro-technicznych wiosną...
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Nowe metody do badań składników obcych w miodach pszczelich
PublikacjaPszczoły, zbierając nektar, pyłek kwiatowy i spadź narażone są na częsty kontakt ze szkodliwymi substancjami (stosowanymi w rolnictwie) osadzonymi na roślinach i przenoszą te zanieczyszczenia - na powierzchni ciała lub wraz z pożytkami - do ula, i w konsekwencji zanieczyszczenia przedostają się do miodu.W związku z możliwością zanieczyszczenia miodu przez pestycydy należące do różnych klas związków chemicznych, pomocne okazuje...