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https://www.readbyqxmd.com/read/28720218/pesticide-analysis-in-coffee-leaves-using-a-quick-easy-cheap-effective-rugged-and-safe-approach-and-liquid-chromatography-tandem-mass-spectrometry-optimization-of-the-clean-up-step
#1
Maria Teresa Salles Trevisan, Robert Wyn Owen, Pau Calatayud-Vernich, Andrea Breuer, Yolanda Picó
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...
July 11, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28720177/validation-of-multiresidue-method-for-analysis-of-31-pesticides-in-rice-using-gas-chromatography-tandem-mass-spectrometry
#2
Rahul Mondal, Ramen Kumar Kole, Anjan Bhttacharyya
Five modified QuEChERS were tested for the multiresidue analysis of 31 pesticides in rice. Rice was spiked with mixture solution of pesticides at 10 ng/g. Method selection was based on the LODs (sensitivity) and recovery tests (accuracy) of the pesticides. Analysis was done in GC-tandem MS in multiple reaction monitoring mode with a total run time of approximately 37 min. The selected method was validated after spiking rice at 20 and 100 ng/g in rice. The performance characteristics of the method impacted for all selected pesticides were acceptable according to the guidelines for method validation (recovery of 70-120% with an RSD of <20% and r2 value of ≥0...
July 1, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28712016/a-survey-of-pesticide-accumulation-in-a-specialist-feeder-the-koala-phascolarctos-cinereus
#3
Caroline Marschner, Damien P Higgins, Mark B Krockenberger
To maintain profitability in Australia's agricultural and urban landscapes pesticides are used throughout the range of koala habitats. The koala is a specialist feeder, reliant on metabolic enzyme capacities to utilise a toxic diet of eucalypt leaves and is potentially prone to adverse effects when xenobiotic interactions between dietary and anthropogenic xenobiotics occur. The aim of this study was to investigate accumulation of frequently used pesticides in wild koalas in 4 areas of New South Wales and Queensland...
July 15, 2017: Bulletin of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/28708032/comparison-of-a-newly-developed-liquid-chromatography-with-tandem-mass-spectrometry-method-and-enzyme-linked-immunosorbent-assay-for-detection-of-multiple-mycotoxins-in-red-pepper-powder
#4
Sunyoung Kim, Sanghee Lee, Tae-Gyu Nam, Dongwon Seo, Miyoung Yoo
In this study, we aimed to establish a method for determination of multiple mycotoxins such as aflatoxins, ochratoxin A, and zearalenone in red pepper powder samples based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach for extraction and cleanup, with detection and quantification by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) in both positive- and negative-ion modes. The developed LC-MS/MS analytical method was compared with an enzyme-linked immunosorbent assay (ELISA) to improve the reliability of our developed method...
July 14, 2017: Journal of Food Protection
https://www.readbyqxmd.com/read/28707620/a-quechers-based-sample-preparation-method-for-the-analysis-of-5-nitroimidazoles-in-bovine-milk-by-hplc-dad
#5
Tomasz Tuzimski, Tomasz Rejczak
In this study, a simple, cost-effective, and sensitive HPLC diode-array detection method was developed for thesimultaneous determination of six different 5-nitroimidazoles [metronidazole, 2-hydroxymethyl-1-methyl-5-nitro-(1)H-imidazole, dimetridazole (DMZ), ronidazole, ornidazole, and ipronidazole] in bovine milk samples. A QuEChERS-based sample preparation procedure was optimized by evaluating different cleanup sorbents, including zirconium-based sorbents (Z-Sep and Z-Sep+), C18, and primary–secondary amine (PSA), as well as EMR-Lipid cleanup solution...
July 13, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28699157/determination-of-cyclic-volatile-methylsiloxanes-in-personal-care-products-by-gas-chromatography
#6
Herbert M Brothers, Thomas Boehmer, Roy A Campbell, Steven Dorn, Joel J Kerbleski, Sarah Lewis, Christian Mund, Donald Pero, Kenji Saito, Michael Wieser, Wolfgang Zoller
OBJECTIVE: Organosiloxanes are prevalent in personal care products (PCPs) due to the desired properties they impart in the usage and application of such products. However, the European Chemical Agency (ECHA) has recently published restriction proposals on the amount of two cyclic siloxanes, octamethylcyclotetrasiloxane (D4) and decamethylcyclotetrasiloxane (D5) allowed in wash off products such as shampoos and conditioners which are discharged down the drain during consumer use. This legislation will require that reliable analytical methods are available for manufacturers and government agencies to use in documenting compliance with the restrictions...
July 12, 2017: International Journal of Cosmetic Science
https://www.readbyqxmd.com/read/28692891/degradation-studies-of-quizalofop-p-and-related-compounds-in-soils-using-liquid-chromatography-coupled-to-low-and-high-resolution-mass-analyzers
#7
Rosalía López-Ruiz, Roberto Romero-González, José Luis Martínez Vidal, Manuel Fernández-Pérez, Antonia Garrido Frenich
A comprehensive degradation study of quizalofop-p, quizalofop-p-ethyl, quizalofop-p-tefuryl and propaquizafop in soil samples have been firstly performed using ultra high performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS). Thus, metabolites or degradation products, such as CHHQ (dihydroxychloroquinoxalin), CHQ (6-chloroquinoxalin-2-ol), PPA ((R)-2-(4-hydroxyphenoxy)propionic acid) and 2,3-dihydroxyquinoxaline were also monitored. An extraction procedure based on QuEChERS procedure was used...
July 7, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28681076/a-multiresidue-method-for-the-analysis-of-90-pesticides-16-pahs-and-22-pcbs-in-honey-using-quechers-spme
#8
Josephine Al-Alam, Ziad Fajloun, Asma Chbani, Maurice Millet
An optimized analytical method was developed for the simultaneous analysis of 90 pesticides, 16 polycyclic aromatic hydrocarbons, and 22 polychlorinated biphenyls. The method was based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction using acetonitrile followed by a dispersive solid-phase extraction cleanup using primary-secondary amine and octadecyl (C18). The extract obtained was concentrated by evaporation and then reconstituted with acetonitrile to prepare it for chromatographic analysis by liquid chromatography-triple-quadrupole tandem mass spectrometry and gas chromatography-ion-trap tandem mass spectrometry, which was preceded by a preconcentration step using solid-phase microextraction with appropriate fibers...
July 5, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28679118/occurrence-of-pesticide-residues-in-spanish-beeswax
#9
Pau Calatayud-Vernich, Fernando Calatayud, Enrique Simó, Yolanda Picó
Beeswax from Spain was collected during 2016 to determine pesticide residues incidence. The 35 samples were divided in foundation, old combs, cappings or virgin beeswax to compare pesticide content between groups. Wax was screened for 58 pesticides or their degradation products by QuEChERS extraction and liquid chromatography mass spectrometry (LC-MS/MS). Beeswax was uniformly contaminated with acaricides and, to a much lesser extent, with insecticide and fungicide residues. Virgin followed by cappings were less contaminated than foundation and old combs beeswax...
July 2, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28679074/occurrence-and-dietary-exposure-assessment-of-pfos-and-pfoa-in-cultured-trachinotus-ovatus-in-china
#10
Di Meng, Mengmeng Guo, Yongzhong Qian, Gang Han
In this study, investigation was conducted into concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in Chinese farmed Trachinotus ovatus between 2014 and 2015 using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) and ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method. The tissue distribution (muscle, skin, liver, kidney and gill) in Trachinotus ovatus was also assessed. The detection frequencies of PFOS and PFOA in fish were 92% and 3%, respectively, and the mean concentrations were 0...
July 5, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/28672694/can-coastline-plant-species-be-used-as-biosamplers-of-emerging-contaminants-uv-filters-and-synthetic-musks-as-case-studies
#11
H Ribeiro, S Ramos, V Homem, L Santos
Personal care products, an important class of emerging contaminants, have been frequently detected in different environmental matrices. Included in this category are synthetic musks compounds (SMCs) and UV-filters. Their occurrence in the coastal environment has been poorly studied. Therefore, this work aimed to verify whether five coastline plant species (Carpobrotus edulis, Cakile maritima, Medicago marina, Elymus farctus borealis-atlanticus and Euphorbia paralias) have the ability to accumulate 11 SMCs (cashmeran, celestolide, phantolide, galaxolide, tonalide, exaltolide, musk moskene, tibetene, ambrette, xylene and ketone) and 2 organic UVB filters (3-(4'-methylbenzylidene) camphor and octocrylene), functioning as biosamplers...
June 20, 2017: Chemosphere
https://www.readbyqxmd.com/read/28668743/uptake-of-the-veterinary-antibiotics-chlortetracycline-enrofloxacin-and-sulphathiazole-from-soil-by-radish
#12
Hyung Suk Chung, Young-Jun Lee, Md Musfiqur Rahman, A M Abd El-Aty, Han Sol Lee, Md Humayun Kabir, Sung Woo Kim, Byung-Jun Park, Jang-Eok Kim, Fazil Hacımüftüoğlu, Nilufar Nahar, Ho-Chul Shin, Jae-Han Shim
Veterinary antibiotics are available for uptake by the plants through sources such as manure, irrigation, and atmospheric interaction. The present study was conducted to estimate the half-lives of three veterinary antibiotics, chlortetracycline (CTC), enrofloxacin (ENR), and sulphathiazole (STZ), in soil and experimentally explore their uptake from contaminated soil to radish roots and leaves. Samples were extracted using a modified citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe "QuEChERS" method followed by liquid chromatography coupled with tandem mass spectrometric analysis (LC-MS/MS) in the positive ion mode...
June 29, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28664337/determination-of-mancozeb-residue-in-fruit-by-derivatization-and-a-modified-quechers-method-using-ultraperformance-liquid-chromatography-tandem-mass-spectrometry
#13
Guofeng Xu, Jiyun Nie, Haifei Li, Zhen Yan, Yang Cheng
A liquid chromatography-tandem mass spectrometry method with derivatization and a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation was developed for the determination of mancozeb in fruits. The target compound was determined in less than 4.0 min with use of an electrospray ionization source in positive mode. The limits of detection and the limits of quantification ranged from 1.0 to 3.2 μg kg(-1) and from 10 to 15 μg kg(-1) in fruit respectively. The linearity was excellent for mancozeb (R (2) ≥ 0...
June 29, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28664334/new-approaches-for-extraction-and-determination-of-betaine-from-beta-vulgaris-samples-by-hydrophilic-interaction-liquid-chromatography-tandem-mass-spectrometry
#14
Luca Rivoira, Sylwia Studzińska, Malgorzata Szultka-Młyńska, Maria Concetta Bruzzoniti, Bogusław Buszewski
Betaine is one of most studied biologically active compounds, due its role in the main biological processes. Although it may be found in several plants and roots, such as the Beta vulgaris family, present in typical diets, just a few analytical methods have been developed for its extraction from roots. A new, quick and effective procedure for the isolation and determination of betaine from two different varieties of B. vulgaris (red and gold) is presented. For betaine extraction, an accelerated solvent extraction (ASE) was coupled with solid-phase extraction...
June 29, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28656556/dissipation-of-s-metolachlor-in-plant-and-soil-and-effect-on-enzymatic-activities
#15
Elżbieta Wołejko, Piotr Kaczyński, Bożena Łozowicka, Urszula Wydro, Andrzej Borusiewicz, Izabela Hrynko, Rafał Konecki, Krystyna Snarska, Dorota Dec, Paweł Malinowski
The present study aimed at evaluating the dissipation of S-metolachlor (S-MET) at three doses in maize growing on diverse physico-chemical properties of soil. The effect of herbicide on dehydrogenase (DHA) and acid phosphatase (ACP) activity was estimated. A modified QuEChERS method using LC-MS/MS has been developed. The limit of quantification (0.001 mg kg(-1)) and detection (0.0005 mg kg(-1)) were very low for soil and maize samples. The mean recoveries and RSDs for the six spiked levels (0.001-0.5 mg kg(-1)) were 91...
July 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28649028/the-optimization-and-establishment-of-quechers-uplc-ms-ms-method-for-simultaneously-detecting-various-kinds-of-pesticides-residues-in-fruits-and-vegetables
#16
REVIEW
Zhan Xiu-Ping, Ma Lin, Huang Lan-Qi, Chen Jian-Bo, Zhao Li
OBJECTIVES: The quality safety supervision and test of agricultural products urgently need a very excellent analytical method with simultaneously detecting many components in order to assess, prevent and control pesticide residues. METHODS: In this research, three fruits and three vegetables produced in Shanghai were selected as the materials, 54 pesticide residues were detected with the ultra-high performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) method on the basis of optimized QuEChERS method according to different materials properties...
June 10, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28647144/simultaneous-determination-of-uv-filters-and-estrogens-in-aquatic-invertebrates-by-modified-quick-easy-cheap-effective-rugged-and-safe-extraction-and-liquid-chromatography-tandem-mass-spectrometry
#17
Ke He, Anne Timm, Lee Blaney
Ultraviolet-filters (UV-filters) and estrogens have attracted increased attention as contaminants of emerging concern (CECs) due to their widespread occurrence in the environment. Most of these CECs are hydrophobic and have the potential to accumulate in aquatic organisms. To date, co-analysis of UV-filters and estrogens has not been reported due, in part, to the complex environmental matrices. Here, a multi-residue method has been developed for simultaneous determination of five UV-filters and three estrogens in tissue from aquatic and marine organisms...
August 4, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28646297/simultaneous-determination-of-aflatoxins-t-2-and-ht-2-toxins-and-fumonisins-in-cereal-derived-products-by-quechers-extraction-coupled-with-lc-ms-ms
#18
Loredana Annunziata, Arianna Stramenga, Pierina Visciano, Maria Schirone, Lorenzo De Colli, Maria Novella Colagrande, Guido Campana, Giampiero Scortichini
A fast, easy, and cheap method for the simultaneous determination and quantification of aflatoxins (B1, B2, G1, G2), T-2 and HT-2 toxins, and fumonisins (B1, B2) in cereal-derived products was developed. This method involved a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction coupled with liquid chromatography-tandem mass spectrometry. The method validation was performed by analyzing samples spiked at four levels, and the recoveries ranged from 83.6 to 102.9%, whereas the maximum values of repeatability and within-laboratory reproducibility were 14...
June 23, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28631158/rapid-and-reliable-steroid-hormone-profiling-in-tursiops-truncatus-blubber-using-liquid-chromatography-tandem-mass-spectrometry-lc-ms-ms
#19
Ashley S P Boggs, Tracey B Schock, Lori H Schwacke, Thomas M Galligan, Jeanine S Morey, Wayne E McFee, John R Kucklick
Monitoring of marine mammal steroid hormone status using matrices alternative to blood is desirable due to the ability to remotely collect samples, which minimizes stress to the animal. However, measurement techniques in alternative matrices such as blubber described to date are limited in the number and types of hormones measured. Therefore, a new method using bead homogenization to QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction, C18 post extraction cleanup and analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed and applied to the measurement of hormone suites in bottlenose dolphin blubber...
June 19, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28624638/the-fate-of-spirotetramat-and-dissipation-metabolites-in-apiaceae-and-brassicaceae-leaf-root-and-soil-system-under-greenhouse-conditions-estimated-by-modified-quechers-lc-ms-ms
#20
Bożena Łozowicka, Patrycja Mojsak, Piotr Kaczyński, Rafał Konecki, Andrzej Borusiewicz
The aim of this study was to investigate the dissipation of spirotetramat and its four metabolites (B-enol, B-keto, B-mono and B-glu) in different parts of vegetables belong to the minor crops (Appiacea and Brassicaceae) and soil from cultivation. The challenge of this study was to apply an optimized clean up step in QuEChERS to obtain one universal sorbent for different complex matrices like leaves with high levels of pigments, roots containing acids, sugars, polyphenolls and pigments and soil with organic ingredients...
June 15, 2017: Science of the Total Environment
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