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QuEChERS

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https://www.readbyqxmd.com/read/28431318/assessing-seasonal-variation-of-synthetic-musks-in-beach-sands-from-oporto-coastal-area-a-case-study
#1
Vera Homem, Inês Magalhães, Arminda Alves, Lúcia Santos
Synthetic musk compounds are widely used in the formulation of several cosmetics, personal care and household products. Due to their massive and widespread use, together with some health concerns, they are considered emerging pollutants and have been detected in different environmental compartments. This study focused on the evaluation of the concentration of synthetic musks (five nitro, five polycyclic and one macrocyclic musks) in beach sands, from Oporto coastal area (Portugal), contributing to the enhancement of the knowledge of levels, trends and behaviour of these compounds in this particular matrix...
April 18, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28417172/simultaneous-determination-of-multiclass-pesticide-residues-in-human-plasma-using-a-mini-quechers-method
#2
Anshuman Srivastava, Satyajeet Rai, Ashish Kumar Sonker, Kajal Karsauliya, Chandra Prabha Pandey, Sheelendra Pratap Singh
Blood is one of the most assessable matrices for the determination of pesticide residue exposure in humans. Effective sample preparation/cleanup of biological samples is very important in the development of a sensitive, reproducible, and robust method. In the present study, a simple, cost-effective, and rapid gas chromatography-tandem mass spectrometry method has been developed and validated for simultaneous analysis of 31 multiclass (organophosphates, organochlorines, and synthetic pyrethroids) pesticide residues in human plasma by means of a mini QuEChERS (quick, easy, cheap, effective, rugged, and safe) method...
April 17, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28410479/analysis-of-sulfonamides-tilmicosin-and-avermectins-residues-in-typical-animal-matrices-with-multi-plug-filtration-cleanup-by-liquid-chromatography-tandem-mass-spectrometry-detection
#3
Yuhong Qin, Freedom Jatamunua, Jingru Zhang, Yanjie Li, Yongtao Han, Nan Zou, Jihao Shan, Yanbin Jiang, Canping Pan
The frequent use of various veterinary drugs could lead to residue bioaccumulation in animal tissues, which could cause dietary risks to human health. In order to quickly analyze the residues, a liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for detecting Sulfonamides, Tilmicosin and Avermectins (AVMs) residues in animal samples. For sample preparation, modified QuEChERS (quick, easy, cheap, effective, rugged and safe) and ultrasound-assisted extraction (UAE) methods were used...
April 2, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28407931/multi-pesticides-residue-analysis-of-grains-using-modified-magnetic-nanoparticle-adsorbent-for-facile-and-efficient-cleanup
#4
Zhenzhen Liu, Peipei Qi, Xiangyun Wang, Zhiwei Wang, Xiahong Xu, Wenxue Chen, Liyu Wu, Hu Zhang, Qiang Wang, Xinquan Wang
A facile, rapid sample pretreatment method was developed based on magnetic nanoparticles for multi-pesticides residue analysis of grains. Magnetite (Fe3O4) nanoparticles modified with 3-(N,N-diethylamino)propyltrimethoxysilane (Fe3O4-PSA) and commercial C18 were selected as the cleanup adsorbents to remove the target interferences of the matrix, such as fatty acids and non-polar compounds. Rice was used as the representative grain sample for method optimization. The amount of Fe3O4-PSA and C18 were systematically investigated for selecting the suitable purification conditions, and the simultaneous determination of 50 pesticides and 8 related metabolites in rice was established by liquid chromatography-tandem mass spectrometry...
September 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28407930/large-scale-multi-class-herbicides-analysis-in-oilseeds-by-rapid-one-step-quechers-based-extraction-and-cleanup-method-using-liquid-chromatography-tandem-mass-spectrometry
#5
Piotr Kaczyński
A simple, sensitive and rapid method is proposed for simultaneous determination of 120 various classes of herbicides in oilseed samples. A one-step QuEChERS-based approach to extraction and cleanup has been developed. LC-MS/MS was used to evaluate the proposed sample treatment methodologies. The new one-step QuEChERS strategy was compared to other methodologies previously used for elimination of co-extracts from fatty matrices. For validation purposes, recovery studies were carried out at 5, 50 and 500µgkg(-1) levels for rapeseed, sunflower seeds and soybean...
September 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28407929/filter-vial-dispersive-solid-phase-extraction-as-a-simplified-clean-up-for-determination-of-ethylphenols-in-red-wines
#6
Ariel R Fontana, Rubén Bottini
In-vial filtration with dispersive solid-phase extraction (d-SPE) clean-up of QuEChERS (quick, easy, cheap, effective, rugged and safe) extracts is proposed for the determination of ethylphenols (EPs) in red wines. Analytes were extracted from 5mL wine sample (previously alkalinized with 0.5% sodium hydroxide) using 5mL acetonitrile. For phase separation, 1.5g NaCl and 4g anhydrous MgSO4 were added. Then, a 0.5mL aliquot of the partitioned supernatant was cleaned-up using d-SPE and in-vial filtration with a combination of anhydrous CaCl2 (100mg) and primary-secondary amine (PSA, 25mg) as sorbents...
September 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28406073/rapid-multi-residue-determination-of-pesticides-in-livestock-muscle-and-liver-tissue-via-modified-quechers-sample-preparation-and-lc-ms-ms
#7
K Hamamoto, K Iwatsuki, R Akama, R Koike
Many multi-residue methods for the determination of pesticides in vegetables and fruits have been reported to date. However, few such methods have been employed to investigate pesticide residues in animal tissue. In this study, an LC/MS/MS multi-residue method coupled with modified QuEChERS extraction was developed and validated for the investigation of eight pesticide residues [prallethrin, resmethrin (RMT), imidacloprid, diflubenzuron, cyromazine (CYR), etofenprox, dinotefuran (DNT), and phthalthrin]. This method involves initial extraction in a water/acetone system, the addition of salts and a subsequent extraction/partitioning step, and finally, a clean-up step utilising dispersive SPE...
April 13, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28402027/simultaneous-determination-of-difenoconazole-trifloxystrobin-and-its-metabolite-trifloxystrobin-acid-residues-in-watermelon-under-field-conditions-by-gc%C3%A2-%C3%A2-ms-ms
#8
Di Kang, Haizhen Zhang, Yuling Chen, Fei Wang, Lihong Shi, Deyu Hu, Kankan Zhang
An optimized QuEChERS method for the simultaneous determination of difenoconazole, trifloxystrobin and its metabolite trifloxystrobin acid residues in watermelon and soil was developed and validated by gas chromatography with tandem mass spectrometry. The samples were extracted with acetonitrile (1% formic acid) and cleaned up by dispersive solid-phase extraction with octadecylsilane sorbent. The limit of quantification of the method was 0.01 mg/kg, and the limit of detection was 0.003 mg/kg for all three analytes...
April 12, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28376431/validation-of-a-quechers-method-for-analysis-of-neonicotinoids-in-small-volumes-of-blood-and-assessment-of-exposure-in-eurasian-eagle-owl-bubo-bubo-nestlings
#9
A Taliansky-Chamudis, P Gómez-Ramírez, M León-Ortega, A J García-Fernández
Neonicotinoid pesticides have gained great interest in the last years both for agricultural and domestic use. Since the information on their environmental distribution or the effects derived from exposure to ecosystems and biota is scarce, new analytical techniques are being developed for monitoring studies. In this sense, two extraction techniques based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) methodology to detect the neonicotinoids authorised in Spain (acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid, nitenpyram and thiamethoxam) were adapted and compared: a) using acetate buffer (AB); and b) using citrate buffer (CB)...
April 1, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28372254/dissipation-kinetics-of-organophosphorus-pesticides-in-milled-toasted-maize-and-wheat-flour-gofio-during-storage
#10
Miguel Ángel González-Curbelo, Bárbara Socas-Rodríguez, Miguel Herrero, Antonio V Herrera-Herrera, Javier Hernández-Borges
The dissipation/degradation of the pesticides dimethoate, terbufos, disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (disulfoton sulfoxide, terbufos sulfone and disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28372248/validation-of-quechers-based-method-for-determination-of-fenitrothion-residues-in-tomatoes-by-gas-chromatography-flame-photometric-detector-decline-pattern-and-risk-assessment
#11
Farag Malhat, Julien Boulangé, Ehab Abdelraheem, Osama Abd Allah, Rania Abd El-Hamid, Shokr Abd El-Salam
A simple and rapid gas chromatography with flame photometric detector (GC-FPD) determination method was developed to detect residue levels and investigate the dissipation pattern and safe use of fenitrothion in tomatoes. A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) using an ethyl acetate-based extraction, followed by a dispersive solid-phase extraction (d-SPE) with primary-secondary amine (PSA) and graphite carbon black (GCB) for clean up, was applied prior to GC-FPD analysis. The method showed satisfactory linearity, recovery and precision...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28372221/dissipation-residues-and-risk-assessment-of-metaldehyde-and-niclosamide-ethanolamine-in-pakchoi-after-field-application
#12
Bizhang Dong, Xingjiao Shao, Hongfang Lin, Jiye Hu
A method using LC-MS/MS after QuEChERS preparation for the simultaneous determination of metaldehyde and niclosamide ethanolamine residues in soil and pakchoi has been developed and validated. The mean recoveries were ranged from 90% to 101% with RSDs (relative standard deviations) less than 9.2%. The dissipation results showed that the half-lives of metaldehyde and niclosamide ethanolamine were 2.3-4.3d and 1.7-9.5d, respectively. The terminal residue results indicated that the residues of metaldehyde in pakchoi were lower than the temporary maximum residue limits (MRL) set by China on 1 d after last treatment and the maximum residue of niclosamide ethanolamine in pakchoi was 0...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28372218/multiresidue-method-for-the-determination-of-pesticides-in-oolong-tea-using-quechers-by-gas-chromatography-triple-quadrupole-tandem-mass-spectrometry
#13
Chia-Chang Wu
We propose a simple, rapid analytical method for determination of 89 pesticides in Oolong tea by GC/MS/MS. Samples were extracted via QuEChERS. The limits of detection and quantification range of the 89 pesticides were 1-25μgL(-1) and 10-50μgL(-1), respectively. Good separation was attained in less than 36min. A wide linear range of 1-250μgL(-1) was observed with r(2) values from 0.9955 to 0.9998. Pesticide-free tea powder spiked at 50 and 100μgL(-1). Recovery ranges of the 86 (50μgL(-1)) and 83 (100μgL(-1)) pesticides were from 60% to 120%...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28372208/modified-quechers-combined-with-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry-to-determine-seven-biogenic-amines-in-chinese-traditional-condiment-soy-sauce
#14
Hao Dong, Kaijun Xiao
A rapid and sensitive UHPLC-MS/MS method followed by modified QuEChERS was developed for the simultaneous determination of seven biogenic amines in soy sauce. Samples were firstly diluted by water and pH values of which were adjusted using ammonia water. Modified QuEChERS method was adopted for the purification and 1, 7-heptyldiamine was used as the internal standard. Analysis of seven biogenic amines was within 4min. Under the optimized conditions, linear relations were favorable over the selected concentration ranges of 3...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28372187/determination-of-mycotoxins-in-plant-based-beverages-using-quechers-and-liquid-chromatography-tandem-mass-spectrometry
#15
Eugènia Miró-Abella, Pol Herrero, Núria Canela, Lluís Arola, Francesc Borrull, Rosa Ras, Núria Fontanals
A method was developed for the simultaneous determination of 11 mycotoxins in plant-based beverage matrices, using a QuEChERS extraction followed by ultra-high performance liquid chromatography coupled to tandem mass spectrometry detection (UHPLC-(ESI)MS/MS). This multi-mycotoxin method was applied to analyse plant-based beverages such as soy, oat and rice. QuEChERS extraction was applied obtaining suitable extraction recoveries between 80 and 91%, and good repeatability and reproducibility values. Method Quantification Limits were between 0...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28372161/disappearance-of-six-pesticides-in-fresh-and-processed-zucchini-bioavailability-and-health-risk-assessment
#16
J Oliva, S Cermeño, M A Cámara, G Martínez, A Barba
A field study was carried out on the dissipation of three insecticides and three fungicides during the freezing of zucchini. A simultaneous residue analysis method is validated using QuEChERS extraction with acetonitrile and CG-MS and LC-MS analysis. The residues detected after field application never exceeded the established maximum residue limits. The processing factors calculated (fresh product/frozen product) are lower than 1, indicating a clear influence of the stages of the freezing process, especially the washing and blanching...
August 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28367868/inhibitory-effects-of-thai-essential-oils-on-potentially-aflatoxigenic-aspergillus-parasiticus-and-aspergillus-flavus
#17
Kittika Jantapan, Amnart Poapolathep, Kanjana Imsilp, Saranya Poapolathep, Phanwimol Tanhan, Susumu Kumagai, Usuma Jermnak
 The antiaflatoxigenic and antifungal activities of essential oils (EOs) of finger root (Boesenbergia rotunda (L.) Mansf.), pine (Pinus pinaster), rosewood (Aniba rosaedora), Siam benzoin (Styrax tonkinensis), Thai moringa (Moringa oleifera), and ylang ylang (Cananga odorata) were tested for Aspergillus parasiticus and Aspergillus flavus in potato dextrose broth. Aflatoxin B1 (AFB1) was extracted from culture using a QuEChERS-based extraction procedure and analyzed with high performance liquid chromatography (HPLC) coupled to a fluorescence detector...
2017: Biocontrol Science
https://www.readbyqxmd.com/read/28363417/multiresidue-determination-of-estrogens-in-different-dairy-products-by-ultra-high-performance-liquid-chromatography-triple-quadrupole-mass-spectrometry
#18
Bárbara Socas-Rodríguez, Antonio V Herrera-Herrera, Javier Hernández-Borges, Miguel Ángel Rodríguez-Delgado
In this work, a simple and fast methodology has been validated and applied for the analysis of a group of 22 estrogenic compounds including eight phytoestrogens (i.e. daidzein, enterodiol, glycitein, enterolactone, genistein, formononetin, prunetin, biochanin A), six mycotoxins (β-zearalanol, β-zearalenol, α-zearalanol, α-zearalenol, zearalanone, zearalenone) as well as four synthetic (i.e. ethynylestradiol, diethylstilbestrol, dienestrol, hexestrol) and four natural estrogens (i.e. estriol, 17β-estradiol, 17α-estradiol, estrone) in different dairy products...
March 19, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28358315/sample-preparation-strategies-for-the-effective-quantitation-of-hydrophilic-metabolites-in-serum-by-multi-targeted-hilic-ms-ms
#19
Elisavet Tsakelidou, Christina Virgiliou, Lemonia Valianou, Helen G Gika, Nikolaos Raikos, Georgios Theodoridis
The effect of endogenous interferences of serum in multi-targeted metabolite profiling HILIC-MS/MS analysis was investigated by studying different sample preparation procedures. A modified QuEChERS dispersive SPE protocol, a HybridSPE protocol, and a combination of liquid extraction with protein precipitation were compared to a simple protein precipitation. Evaluation of extraction efficiency and sample clean-up was performed for all methods. SPE sorbent materials tested were found to retain hydrophilic analytes together with endogenous interferences, thus additional elution steps were needed...
March 30, 2017: Metabolites
https://www.readbyqxmd.com/read/28353394/lc-ms-ms-determination-of-pesticide-residues-in-fruits-and-vegetables
#20
Anna Stachniuk, Agnieszka Szmagara, Renata Czeczko, Emilia Fornal
The aim of the research is to evaluate pesticide residue contamination of fresh and frozen fruits and vegetables, agricultural raw material, purchased from Polish farmers for production of frozen fruits and vegetables, and the estimation of the multiresidue method effectiveness expressed as the proportion of pesticides detected in food samples to the total number of pesticides analyzed by multiresidue methods. A total of 144 samples (of black currants, red currants, raspberries, cherries, strawberries, blackberries, cauliflowers and broccoli) were analyzed using LC-MS/MS method for the determination of 60 pesticides...
March 29, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
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