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Rocha D.G.,Federal University of Minas Gerais | Santos F.A.,Laboratorio Nacional Agropecuario LANAGRO MG | da Silva J.C.C.,Federal University of Minas Gerais | Augusti R.,Federal University of Minas Gerais | Faria A.F.,Federal University of Minas Gerais
Journal of Chromatography A | Year: 2015

This work involved the optimization and validation of two methods according to the Commission Decision 2002/657/EC directives for determining fluoroquinolones residues in samples of poultry muscle and kidney: ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, nalidixic acid, norfloxacin, ofloxacin, oxolinic acid, pipemidic acid and sarafloxacin. The extraction procedure was based on a QuEChERS approach, whose optimization employed a Box-Behnken 33 factorial design. A liquid chromatography-tandem mass spectrometry method (LC-MS/MS) was developed for determining the twelve analytes using the multiple reaction monitoring mode (MRM). Accuracy, evaluated by recovery studies, varied from 88.8 to 112.2% for the selected levels with RSD values lower than 12.3%. The second validated method employed high resolution mass spectrometry (HRMS) performed in the single ion monitoring mode (SIM), determining nine among twelve analytes. The validation parameters were evaluated as satisfactory, with recoveries from 82.5 to 114.4% and RSD lower than 8.7%. Decision limits and detection capabilities for both methods were reported. The two methods were statistically compared using the Student's t test, at 95% confidence level, resulting in no significant difference. © 2015 . Source

Pacifico da Silva I.,Rural University | Oliveira F.A.S.,Laboratorio Nacional Agropecuario LANAGRO MG | Oliveira F.A.S.,Federal University of Minas Gerais | Pedroza H.P.,Federal University of Minas Gerais | And 3 more authors.
Apidologie | Year: 2015

The decline of honeybee (Apis mellifera L.) populations impacts global agricultural production and affects both food production and the economy. One of the probable causes for this decline is the indiscriminate use of pesticides. Here, we compare the levels of pesticide exposure among honeybees that are used to pollinate melon (Cucumis melo L.) crops, honeybees that forage in the forest, and stingless bees, Melipona subnitida, that forage in the forest. The level of pesticide exposure was determined by measuring residual pesticide levels of 152 compounds in the honey. Honey samples from the present study contained 19 different pesticides, 13 of which were present in honey from bees pollinating melon crops. The levels of some compounds were sufficiently high to promote toxic effects in the bees. Thus, crop pollination presents a toxicological risk to bees that may reduce their life span. © 2014, INRA, DIB and Springer-Verlag France. Source

Cassimiro Belo R.F.,Federal University of Minas Gerais | Nunes C.M.,Laboratorio Nacional Agropecuario LANAGRO MG | Vieira Dos Santos E.,Laboratorio Nacional Agropecuario LANAGRO MG | Augusti D.V.,Laboratorio Nacional Agropecuario LANAGRO MG | Pissinatti R.,Laboratorio Nacional Agropecuario LANAGRO MG
Analytical Methods | Year: 2012

This article describes a method for the quantification of seven Polycyclic Aromatic Hydrocarbons (PAHs) in edible oils (soy, sunflower and olive). It involved the application of a low-volume liquid-liquid extraction (LLE) technique followed by a solid-phase extraction (SPE) clean-up with C 18 and silica cartridges. Separation and analysis of compounds were performed by gas chromatography coupled to mass spectrometry (GC-MS). 13C-labeled PAHs as internal standards were used to aid the identification of compounds and to determine the efficiency of the extraction method in an isotope dilution mass spectrometry (IDMS) approach. Low-volume LLE and SPE clean-up procedures allowed the reduction of solvent consumption, eliminated the necessity of a previous saponification step and provided less sample preparation time when compared to traditional PAHs extraction and clean-up methods. The analytical procedure was validated according to recommendations of the European Commission Decision 2002/657/EC and European Commission Regulations (2007/333/EC and 2011/836/EU). Acceptable values (except for chrysene) were obtained for the following parameters: linearity (r 2 > 0.98), limit of quantification (0.12 < LOQ < 0.68 μg kg-1), limit of detection (0.04 < LOD < 0.23 μg kg -1), trueness (recovery rates and certified reference material normalized error), and precision (repeatability and intermediate precision). Recoveries higher than 80% were attained for seven PAHs, at three concentration levels (0.75, 2.00 and 4.00 μg kg-1). This validated method will be used by the Ministry of Agriculture, Livestock and Food Supply in Brazil. © 2012 The Royal Society of Chemistry. Source

Lopes R.P.,Federal University of Minas Gerais | De Freitas Passos T.E.,Laboratorio Nacional Agropecuario LANAGRO MG | De Alkimim Filho J.F.,Laboratorio Nacional Agropecuario LANAGRO MG | Vargas E.A.,Laboratorio Nacional Agropecuario LANAGRO MG | And 2 more authors.
Food Control | Year: 2012

A multiresidue method for the quantification of 13 sulfonamides in animal feed is described. It involves the application of a modified QuEChERS procedure followed by HPLC-MS/MS (high performance liquid chromatography coupled to tandem mass spectrometry) analysis. The best conditions for the extraction solution and PSA (primary secondary amine) mass were determined. After optimization, the method was validated according to the European Commission Decision 2002/657/EC. The validation levels employed were 25, 50 and 75 μg kg -1. Acceptable values were obtained for the following parameters: linearity (0.9864 < r 2 < 0.9993), decision limit (50.4 μg kg -1 < CC α < 55.8 μg kg -1), detection capability (50.7 μg kg -1 Source

Souza Dibai W.L.,Laboratorio Nacional Agropecuario LANAGRO MG | De Alkimin Filho J.F.,Laboratorio Nacional Agropecuario LANAGRO MG | Da Silva Oliveira F.A.,Laboratorio Nacional Agropecuario LANAGRO MG | Sampaio De Assis D.C.,Federal University of Minas Gerais | And 3 more authors.
Talanta | Year: 2015

Abstract Carbadox (CBX) and olaquindox (OLA) were used in poultry and swine feed for growth promotion, to improve feed efficiency and increase the rate of weight gain. However, the use of these agents in feedingstuffs was prohibited because of concerns about their toxicity. Regulatory laboratories are required to have suitably validated analytical methods to ensure compliance with the ban. A quantitative and confirmatory method for determining the presence of CBX and OLA in poultry and swine feed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed, optimized, and validated. The analytes extraction was performed with a mixture of water and acetonitrile (1:1 v/v) and cleanup with hexane and C18 (dispersive phase). The method was evaluated by the following parameters: specificity, linearity, matrix effect, decision limits (CCα), detection capability (CCβ), accuracy, precision, limits of detection (LoD), limits of quantification (LoQ) and measurement uncertainty. The validated method presented a broad linear study range and no significant matrix effect. The limit of detection (LoD) was defined at 9 μg kg-1 for CBX and 80 μg kg-1 for OLA, and the limit of quantification (LoQ) was defined at 12 μg kg-1 and 110 μg kg-1 for CBX and OLA, respectively. The accuracy of the method was adequate for CBX and OLA. The recovery values found in the repeatability conditions were 99.41% for CBX and 104.62% for OLA. Under intralaboratory reproducibility conditions, the values were 98.63% for CBX and 95.07% for OLA. It was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of CBX and OLA in poultry and swine feedingstuffs. © 2015 The Authors. Source

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