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Paola A Magni, Marco Pazzi, Marco Vincenti, Valerio Converso, Ian R Dadour
Entomotoxicology studies employ analytical methods and instrumentation to detect chemical substances in carrion insects feeding from the decomposing tissues. The identification of such chemicals may determine the cause of death and may be used for the estimation of the minimum time since death. To date, the main focus of entomotoxicological studies has been the detection of drugs, whereas little information concerns the effects of pesticides on blowflies. Pesticides are generally freely available and more affordable than drugs but they can also be a home hazard and an accessible candidate poison at a crime scene...
October 4, 2017: Journal of Medical Entomology
Jian Zhou, Jiao-Jiao Xu, Zeng-Xuan Cai, Bai-Fen Huang, Mi-Cong Jin, Yi-Ping Ren
Two analytical approaches, including ultra-high performance liquid chromatograph linked with photo-diode array/fluorescence detector, and ultra-high performance liquid chromatography-tandem mass spectrometry, have been proposed for simultaneous determination of five Alternaria toxins in cereals, which both based on QuEChERS strategy. After QuEChERS extraction and salting out, the collected supernatant was subjected to an extra dispersive liquid-liquid microextraction step prior to quantitative analysis. Response surface methodology based on central composite design was employed to optimize the micro-extraction conditions...
October 4, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Kwenga Sichilongo, Elliott Mwando, Enoch Sepako, Amos Massele
INTRODUCTION: Sample preparation in bio analytical chemistry poses a challenge because it can be compound dependent. We compared six sample extraction techniques i.e. QuEChERS (Q), liquid extraction (LE), protein precipitation (PPT), Q-PPT, Q-LE and LE-PPT for the extraction of antiretroviral drugs emtricitabine, tenofovir, efavirenz, lopinavir and rotinavir in human blood plasma. METHOD: A multiple reaction monitoring liquid chromatography- tandem mass spectrometry method for the determination of the same antiretroviral drugs developed and validated in this laboratory was used...
October 5, 2017: Journal of Pharmacological and Toxicological Methods
M D H Prodhan, Emmanouil-N Papadakis, Euphemia Papadopoulou-Mourkidou
BACKGROUND: Variability of pesticide residues among food items is very important when assessing the risks and food safety for the consumers. Therefore, the present study was undertaken to estimate the unit-to-unit residue variability factors for eggplant. RESULTS: In total 120 samples from a trial field and 142 samples from different marketplaces in Thessaloniki, Greece were collected to estimate the variability of pesticide residues in eggplant units. They were extracted by QuEChERS method and the residues were determined by LC-MS/MS...
October 6, 2017: Journal of the Science of Food and Agriculture
Xiao-Jun Chen, Zhi-Yuan Meng, Li Ren, Yue-Yi Song, Ya-Jun Ren, Jian-Shu Chen, Ling-Jun Guan
With the purpose of guaranteeing the safe use of spirotetramat and preventing its potential health threats toconsumers, a QuEChERS extraction method coupled with LC triple-quadrupole tandem MS was applied in this study to determine residual spirotetramat metabolites in different tissues of amaranth (Amaranthus tricolor) and in soil. The results indicate that the spirotetramat degraded into different types of metabolites that were located in different tissues of amaranth and in soil. B-keto, B-glu, and B-enol were the three most representative degradation products in the leaf of amaranth, and B-glu and B-enol were the two major degradation products found in the stem of amaranth; however, only B-enol was detected in the root of amaranth...
October 5, 2017: Journal of AOAC International
Han-Yin Hsiao, Bing Huei Chen, Tsai Hua Kao
The traditional way to analyze heterocyclic amines (HAs) is time-consuming and uses large amounts of solvents. The objective of this study is to develop a quick and simultaneous analysis method for multiple types of HAs contained in meat products. Results showed that 20 HAs and 1 internal standard (4,7,8-TriMeIQx) can be separated within 30 min using an Inspire C18 column and a gradient solvent system containing a 10-mM ammonium acetate (pH 2.9) and acetonitrile. This process resulted in a high degree of separation...
October 3, 2017: Journal of Agricultural and Food Chemistry
Nadeem Muhammad, Qamar Subhani, Fenglian Wang, Chaoyan Lou, Junwei Liu, Yan Zhu
A new simple, isocratic, selective and highly sensitive method has been developed for the simultaneous separation and determination of two plant growth regulators (PGRs): 2-(1-Naphthyl)acetic acid (NAA) and 2-(Naphthalen-1-yl)acetamide (NAD). Both PGRs were extracted by modified and miniaturized ion chromatography-Quick, Easy, Cheap, Effective, Rugged and Safe (IC-QuEChERS) method from ten food samples. The separation and sensitive determination were carried out by using ion chromatography coupled with fluorescence and ultraviolet (IC-FLD/UV) detector...
February 15, 2018: Food Chemistry
A Suganthi, K Bhuvaneswari, M Ramya
A simple, sensitive and inexpensive LC-MS/MS method was developed and validated for for the simultaneous detection and quantification of (five) neonicotinoid insecticides in sugarcane juice. The juice samples were extracted with acetonitrile and subsequent cleanup was done by dispersive solid-phase extraction (QuEChERS method). The quantification was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionization source (LC-ESI-MS/MS). After the optimization of the extraction parameters, the method was validated by evaluating linearity, limits of detection and quantification, precision (repeatability) and accuracy (recovery)...
February 15, 2018: Food Chemistry
Zareen Khan, Narayan Kamble, Aarti Bhongale, Madhuri Girme, Vijay Bahadur Chauhan, Kaushik Banerjee
Tuber crops substantially contribute to the food security in the developing countries. Often, their cultivation involves unregulated applications of pesticides, leading to MRL non-compliances. Despite their rising currency in international trade, there exist scarcely any methods for pesticide residue analysis in these matrices. Therefore, we developed a multi-residue method for simultaneous analysis of a diverse range of pesticides in tuber crops, based on pressurized liquid extraction by ethyl acetate, followed by selective identification and quantification of the residues using GC-MS selected reaction monitoring...
February 15, 2018: Food Chemistry
Godfred Darko, Jonah Addai Tabi, Michael Kodwo Adjaloo, Lawrence Sheringham Borquaye
Concentrations of pesticides residues in honey sampled from the major honey producing forest belts in Ghana were determined. Samples were purposively collected and extracted using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method and analysed for synthetic pyrethroids, organochlorine, and organophosphate pesticide residues. Aldrin, γ-HCH, β-HCH, ∑endosulfan, cyfluthrin, cypermethrin, deltamethrin, permethrin methoxychlor, ∑DDT, chlorpyrifos, fenvalerate, malathion, dimethoate, and diazinon were all detected at the concentration of 0...
2017: Journal of Environmental and Public Health
Miguel A Camara, Alberto Barba, Sandra Cermeño, Gracia Martinez, Jose Oliva
The aim of this research is to establish the processing factors of six pesticides durong the preparation of fresh-cut lettuce and to assess the risk of ingestion of pesticide residues associated with the consumption of the same. A field study was carried out on the dissipation of three insecticides (imidacloprid, tebufenozide, cypermethrin) and three fungicides (metalaxyl, tebuconazole, azoxystrobin) during treatment conditions simulating those used for commercial fresh-cut lettuce. A simultaneous residue analysis method is validated using QuEChERS extraction with acetonitrile and CG-MS and LC-MS/MS analysis...
September 26, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
Weiwei Yu, Min Huang, Jiaojiao Chen, Sizhuo Wu, Kunming Zheng, Song Zeng, Kankan Zhang, Deyu Hu
Residues of dinotefuran and its metabolites, 1-methyl-3-(tetrahydro-3-furylmethyl)urea (UF) and 1-methyl-3-(tetrahydro-3-furylmethyl)guanidine (DN), in apple were investigated using a "QuEChERS" (quick, easy, cheap, effective, rugged, safe) pretreatment and liquid chromatography-tandem mass spectrometry. Limits of detection (LODs) and quantification (LOQs) of dinotefuran, UF, and DN in apples were 0.011-0.960 and 0.037-3.200 μg/kg, respectively. The average recoveries of dinotefuran, UF, and DN in apple ranged from 70...
September 26, 2017: Environmental Monitoring and Assessment
Mohammad Faraji, Roya Noorbakhsh, Hooshang Shafieyan, Mohammadkazem Ramezani
A QuEChERS based methodology was developed for the simultaneous identification and quantification of acetamiprid, imidacloprid, and spirotetramat and their relevant metabolites in pistachio by liquid chromatography-tandem mass spectrometry for the first time. First, sample extraction was done with MeCN:citrate buffer:NaHCO3 followed by phase separation with the addition of MgSO4:NaCl. The supernatant was then cleaned by a primary-secondary amine (PSA), GCB, and MgSO4. The proposed method provides a linearity in the range of 5-200µgL(-1), and the linear regression coefficients were higher than 0...
February 1, 2018: Food Chemistry
Jean Lucas de Oliveira Arias, Antunielle Schneider, Jahir Antonio Batista-Andrade, Augusto Alves Vieira, Sergiane Souza Caldas, Ednei Gilberto Primel
Clean extracts are essential in LC-MS/MS, since the matrix effect can interfere in the analysis. Alternative materials which can be used as sorbents, such as chitosan in the clean-up step, are cheap and green options. In this study, chitosan from shrimp shell waste was evaluated as a sorbent in the QuEChERS method in order to determine multi-residues of veterinary drugs in different types of milk, i. e., fatty matrices. After optimization, the method showed correlation coefficients above 0.99, LOQs ranged between 1 and 50μgkg(-1) and recoveries ranged between 62 and 125%, with RSD<20% for all veterinary drugs in all types of milk under study...
February 1, 2018: Food Chemistry
Ahmad Hanafi, Marilena Dasenaki, Anna Bletsou, Nikolaos S Thomaidis
Two QuEChERS-based methods were developed and validated, using liquid chromatography-tandem mass spectrometric detection, in order to accurately determine residues of imidacloprid and oxamyl in green beans and chili peppers after treatment via irrigation system under field conditions in Egyptian farms. The validation included experiments for specificity, linearity, trueness, precision, matrix effect and limits of detection and quantification according to European Commission standards. The dissipation rates of both pesticides in green beans and chili peppers were studied and the pre-harvest intervals (PHIs) were calculated...
February 1, 2018: Food Chemistry
Fei Zhao, Xin Gao, Zhixu Tang, Xin Luo, Miaomiao Wu, Jiachao Xu, Xiaoting Fu
A simple, rapid and sensitive multi-residue analytical method was developed and validated for 80 veterinary drugs in Oplegnathus punctatus using ultrahigh performance liquid chromatography-Orbitrap high resolution mass spectrometry (LC-HRMS). The analytes belong to 12 different families include benzimidazoles, β-lactams, lincosamides, macrolides, nitromidazoles, quinolones, sulfonamides and trimethoprim, tetracyclines, triphenylmethane dyes, amphenicols, nonsteroidal estrogens and steroid hormones. The sample preparation was optimized base on QuEChERS (quick, easy, cheap, effective, rugged and safe) procedure...
September 18, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Jishi Wang, Zeying He, Lu Wang, Yaping Xu, Yi Peng, Xiaowei Liu
In this research, the manual two-step QuEChERS approach has been streamlined and automated into a one-step method using a cleanup tube fitted within an extraction tube. A novel automatic QuEChERS combination have been developed to simplify the QuEChERS procedures and improve sample preparation efficiency. This combination integrates QuEChERS procedures into a single run via the use of a vortex vibration-centrifuge device and a centrifuge filtration tube. To validate the efficiency of our automatic QuEChERS device, 270 pesticides were analyzed in plant origined foods including celery, tomatoes, leeks, eggplants, grapes, corn, green tea, and soybean oil using this automatic platform...
September 18, 2017: Journal of Chromatography. A
Maheswor Gautam, Inge S Fomsgaard
Lettuce is an important part of the diet in Europe. The permitted levels of pesticides in lettuce are strictly regulated and there is growing urge among food safety authorities to analyse pesticide metabolites as well. Azoxystrobin is one of pesticides that is frequently detected in lettuce. Although there are several analytical methods for the determination of azoxystrobin in lettuce, a sensitive method for the determination of its metabolites in lettuce is lacking. This study aimed at developing an extraction and LC-MS/MS method for the simultaneous determination of azoxystrobin, and its metabolites azoxystrobin free acid and 2-hydroxybenzonitrile in lettuce...
September 21, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
Chun Li, Xiao Su, Wei-Hong Feng, Rao-Rao Li, Xiao-Qian Liu, Peng-Yue Li, Zhi-Min Wang
To investigate the cause of liver toxicity induced by Polygoni Multiflori Radix through determining various mycotoxins in it. An UPLC-ESI-MS/MS method was developed and established to simultaneously determine 12 mycotoxins, Aflatoxins B₁, B₂, G₁, G₂, Ochratoxins A and B, Fumonisins B₁ and B₂,T-2 toxin, HT-2 toxin, Deoxynivalenol and Zearalenone, in rawand processed Polygon iMultiflori Radix. The sample was extracted with modified QuEChERS method, and then was separatedon a WelchUltimate XBC₁₈ column by gradient elution using methanol and 2 mmol•L⁻¹ ammonium acetate aqueous solution containing 0...
December 2016: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
In Kyung Kim, Sung-Woo Kim, A M Abd El-Aty, Md Musfiqur Rahman, Md Humayun Kabir, Han Sol Lee, Hyung Suk Chung, Ji Hoon Jeong, Ho-Chul Shin, Jae-Han Shim
The present study was designed to investigate the residual decline pattern and the risk assessment of 10 different class pesticides, namely azoxystrobin, boscalid, diazinon, diethofencarb, difenoconazole, etofenprox, flubendiamide, paclobutrazol, and pyraclostrobin in young vegetative amaranth (Amaranthus mangostanus) sprayed once or twice under greenhouse growing conditions. Field-incurred samples, collected at 3, 7, or 10 days after application of both treatments, were extracted and purified with the quick, easy, cheap, effective, rugged, and safe "QuEChERS" citrate-buffered method and analyzed with liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS) in positive ion mode...
September 16, 2017: Environmental Science and Pollution Research International
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