The Experts below are selected from a list of 87 Experts worldwide ranked by ideXlab platform
Roberto Romero-gonzález - One of the best experts on this subject based on the ideXlab platform.
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Multiresidue method for fast determination of pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry.
Talanta, 2008Co-Authors: Roberto Romero-gonzález, Antonia Garrido Frenich, J. L. Martínez VidalAbstract:Abstract A new analytical method for the simultaneous determination of 90 pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC–MS/MS) has been developed and validated. Extraction was performed with acetonitrile, applying QuEChERS methodology, and the extracts were analyzed without any further clean-up step, providing better results than solid phase extraction (SPE) procedure. Before chromatographic step, extracts were diluted with water (1:1) in order to obtain good peak shapes. Several chromatographic conditions were evaluated in order to achieve a fast separation in Multiple Reaction Monitoring (MRM) mode, obtaining a run time of only 11 min. Matrix effect was studied for different types of fruit juices (peach, orange, pineapple, apple and multifruit), indicating that multifruit juice can be selected as Representative Matrix for routine analysis of these food commodities. Pesticides were quantified using Matrix-matched calibration with recoveries between 70.4 and 108.5% and relative standard deviation lower than 20%. Limits of quantification were lower than 5 μg L −1 in all the cases. The developed procedure was applied to commercial fruit juices, detecting carbendazim, cyprodinil and thiabendazol in a few samples.
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Application of hollow fiber supported liquid membrane extraction to the simultaneous determination of pesticide residues in vegetables by liquid chromatography/mass spectrometry.
Rapid communications in mass spectrometry : RCM, 2006Co-Authors: Roberto Romero-gonzález, Elena Pastor-montoro, J. L. Martínez-vidal, Antonia Garrido-frenichAbstract:A new analytical procedure using a hollow fiber supported liquid membrane (HFSLM) has been developed for the simultaneous determination of pesticide residues in vegetables by liquid chromatography (LC) coupled with electrospray mass spectrometry (MS). The extraction technique requires minimal sample preparation and solvent consumption. Optimum extraction conditions have been evaluated with respect to sample pH, ionic strength, liquid membrane composition, extraction time, stirring rate and acceptor composition. The extraction method has been validated for matrices such as cucumber, tomato and pepper, indicating that cucumber can be selected as Representative Matrix for routine analysis of these food commodities. Linear ranges of pesticides in vegetable samples were 10 to 200 microg/kg, and the repeatability of the method was less than 20% for the lowest calibration point. The limits of detection ranged from 0.06 to 2.7 microg/kg and the limits of quantification from 0.2 to 9.0 microg/kg, which were low enough to determine the pesticide residues at concentrations below or equal to the maximum residue levels (MRLs) specified by European Union. The method was finally applied to the determination of more than 20 pesticides in market vegetable samples and the concentrations found in these samples were always lower than the MRLs. This new approach can be considered as a powerful alternative to the traditional extraction techniques.
J. L. Martínez Vidal - One of the best experts on this subject based on the ideXlab platform.
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Multiresidue method for fast determination of pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry.
Talanta, 2008Co-Authors: Roberto Romero-gonzález, Antonia Garrido Frenich, J. L. Martínez VidalAbstract:Abstract A new analytical method for the simultaneous determination of 90 pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC–MS/MS) has been developed and validated. Extraction was performed with acetonitrile, applying QuEChERS methodology, and the extracts were analyzed without any further clean-up step, providing better results than solid phase extraction (SPE) procedure. Before chromatographic step, extracts were diluted with water (1:1) in order to obtain good peak shapes. Several chromatographic conditions were evaluated in order to achieve a fast separation in Multiple Reaction Monitoring (MRM) mode, obtaining a run time of only 11 min. Matrix effect was studied for different types of fruit juices (peach, orange, pineapple, apple and multifruit), indicating that multifruit juice can be selected as Representative Matrix for routine analysis of these food commodities. Pesticides were quantified using Matrix-matched calibration with recoveries between 70.4 and 108.5% and relative standard deviation lower than 20%. Limits of quantification were lower than 5 μg L −1 in all the cases. The developed procedure was applied to commercial fruit juices, detecting carbendazim, cyprodinil and thiabendazol in a few samples.
Ana M Garciacampana - One of the best experts on this subject based on the ideXlab platform.
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use of an ionic liquid based surfactant as pseudostationary phase in the analysis of carbamates by micellar electrokinetic chromatography
Electrophoresis, 2015Co-Authors: Carmen Tejadacasado, David Morenogonzalez, Ana M Garciacampana, Monsalud Del OlmoiruelaAbstract:The applicability of an ionic liquid-based cationic surfactant 1-dodecyl-3-methyl-imidazolium tetrafluoroborate (C12 MImBF4 ) as pseudostationary phase in MEKC has been evaluated for the analysis of 11 carbamate pesticides (promecarb, carbofuran, metolcarb, fenobucarb, aldicarb, propoxur, asulam, benomyl, carbendazim, ethiofencarb, isoprocarb) in juice samples. Under optimum conditions (separation buffer, 35 mM NaHCO3 and 20 mM C12 MImBF4 , pH 9.0; capillary temperature 25°C; voltage -22 kV) the analysis was carried out in less than 12 min, using hydrodynamic injection (50 mbar for 7.5 s) and detection at 200 nm. For the extraction of these CRBs from juice samples, a dispersive liquid-liquid microextraction (DLLME) procedure has been proposed, by optimization of variables affecting the efficiency of the extraction. Following this treatment, sample throughput was approximately 12 samples per hour, obtaining a preconcentration factor of 20. Matrix-matched calibration curves were established using tomato juice as Representative Matrix (from 5 to 250 μg/L for CBZ, BY, PX, CF, FEN, ETH, ISP, and 25-250 μg/L for ASL, ALD, PRC, MTL), obtaining quantification limits ranging from 1 to 18 μg/L and recoveries from 70 to 96%, with RSDs lower than 9%.
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a new approach in sample treatment combined with uhplc ms ms for the determination of multiclass mycotoxins in edible nuts and seeds
Talanta, 2013Co-Authors: Natalia Arroyomanzanares, Jose F Huertasperez, Laura Gamizgracia, Ana M GarciacampanaAbstract:Abstract A sensitive, simple and rapid method for the determination of fourteen mycotoxins in nuts and seeds (including almonds, peanuts, sunflower seeds, pumpkin seeds, walnuts, macadamia nuts, pistachios, hazelnuts and pine nuts) has been developed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The sample treatment comprises a first step based on QuEChERS procedure for the determination of fumonisin B 1 , fumonisin B 2 , deoxynivalenol, fusarenon-X, T-2 and HT-2 toxin, citrinin, sterigmatocystin, zearalenone and ochratoxin A. A subsequent clean-up step based on the dispersive liquid–liquid microextraction (DLLME) was necessary for the determination of aflatoxins (B 1 , B 2 , G 1 and G 2 ), since their determination was not possible applying only the QuEChERS-based extraction. The method was validated for peanuts as Representative Matrix and was subsequently evaluated for the other eight matrices. Quantification limits obtained for aflatoxins, the unique mycotoxins legislated on these matrices, were lower than the maximum levels allowed by the current legislation, while quantification limits obtained for the other mycotoxins were lower than the limits usually permitted by the legislation in other food matrices. Precision of the method was always lower than 11%, and recoveries ranged between 60.7% and 104.3%.
Antonia Garrido Frenich - One of the best experts on this subject based on the ideXlab platform.
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analysis of pesticide and veterinary drug residues in baby food by liquid chromatography coupled to orbitrap high resolution mass spectrometry
Talanta, 2015Co-Authors: Maria Luz Gomezperez, Roberto Romerogonzalez, Vidal Jose Luis Martinez, Antonia Garrido FrenichAbstract:Abstract Pesticide and veterinary drug residues have been simultaneously determined in several baby foods as meat, fish and vegetable-based baby food. A generic extraction method without clean-up step was applied. Moreover, the use of a Representative Matrix for proper quantification of all target compounds was studied and the best results were obtained when vegetable-based baby food was used as Representative Matrix, allowing the reliable quantification of more than 300 compounds. The method was validated and good recoveries were obtained for most of compounds at concentrations higher than 50 µg kg−1. Limits of detection (LOD) ranged from 0.5 to 50 µg kg−1, whereas limits of quantification (LOQ) were established between 10 and 100 µg kg−1. Limits of identification (LOIs) ranged from 0.5 to 50 µg kg−1. This method was applied to the analysis of 46 different baby food samples and no positive samples were found.
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Multiresidue method for fast determination of pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry.
Talanta, 2008Co-Authors: Roberto Romero-gonzález, Antonia Garrido Frenich, J. L. Martínez VidalAbstract:Abstract A new analytical method for the simultaneous determination of 90 pesticides in fruit juices by ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC–MS/MS) has been developed and validated. Extraction was performed with acetonitrile, applying QuEChERS methodology, and the extracts were analyzed without any further clean-up step, providing better results than solid phase extraction (SPE) procedure. Before chromatographic step, extracts were diluted with water (1:1) in order to obtain good peak shapes. Several chromatographic conditions were evaluated in order to achieve a fast separation in Multiple Reaction Monitoring (MRM) mode, obtaining a run time of only 11 min. Matrix effect was studied for different types of fruit juices (peach, orange, pineapple, apple and multifruit), indicating that multifruit juice can be selected as Representative Matrix for routine analysis of these food commodities. Pesticides were quantified using Matrix-matched calibration with recoveries between 70.4 and 108.5% and relative standard deviation lower than 20%. Limits of quantification were lower than 5 μg L −1 in all the cases. The developed procedure was applied to commercial fruit juices, detecting carbendazim, cyprodinil and thiabendazol in a few samples.
Renjiang Liu - One of the best experts on this subject based on the ideXlab platform.
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a multi residue method for fast determination of pesticides in tea by ultra performance liquid chromatography electrospray tandem mass spectrometry combined with modified quechers sample preparation procedure
Food Chemistry, 2011Co-Authors: Guoqiang Chen, Pengying Cao, Renjiang LiuAbstract:Abstract A multi-residue method was developed for rapid determination of pesticide residues in tea by ultra performance liquid chromatography–electrospray tandem mass spectrometry (UPLC/MS/MS). The QuEChERS method was used for sample preparation. In order to minimise the Matrix effects from tea, a solid phase extraction (SPE) cartridge layered with graphite carbon/aminopropylsilanized silica gel was applied as complementary to QuEChERS method. For accurate quantification, Representative Matrix-matched calibration curves were applied to compensate Matrix effects. Limits of quantification varied with different pesticides but all can be measured at 0.01 mg kg−1 level in a 5 g tea sample except dichlorvos (0.02 mg kg−1). Recoveries ranged from 70% to 120% and relative standard deviation (RSD) met the European United Quality Control guideline. Efficiency and reliability of this method were investigated by the analysis of both fermented and unfermented Chinese tea samples.