The Experts below are selected from a list of 6828 Experts worldwide ranked by ideXlab platform
Jerry Zweigenbaum - One of the best experts on this subject based on the ideXlab platform.
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Comparison of veterinary Drug Residue results in animal tissues by ultrahigh-performance liquid chromatography coupled to triple quadrupole or quadrupole–time-of-flight tandem mass spectrometry after different sample preparation methods, including us
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Tarun Anumol, Steven J. Lehotay, Joan Stevens, Jerry ZweigenbaumAbstract:Veterinary Drug Residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in Drug Residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the Drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-Residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography–tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 Drugs at regulatory levels of concern in animal tissues. Recently, a new cleanup product called “enhanced matrix removal for lipids” (EMR-L) was commercially introduced that used a unique chemical mechanism to remove lipids from extracts. Furthermore, high-resolution quadrupole–time-of-flight (Q/TOF) for (U)HPLC detection often yields higher selectivity than targeted QQQ analyzers while allowing retroactive processing of samples for other contaminants. In this study, the use of both d-SPE and EMR-L sample preparation and UHPLC-QQQ and UHPLC-Q/TOF analysis methods for shared spiked samples of bovine muscle, kidney, and liver was compared. The results showed that the EMR-L method provided cleaner extracts overall and improved results for several anthelmintics and tranquilizers compared to the d-SPE method, but the EMR-L method gave lower recoveries for certain β-lactam antibiotics. QQQ vs. Q/TOF detection showed similar mixed performance advantages depending on analytes and matrix interferences, with an advantage to Q/TOF for greater possible analytical scope and non-targeted data collection. Either combination of approaches may be used to meet monitoring purposes, with an edge in efficiency to d-SPE, but greater instrument robustness and less matrix effects when analyzing EMR-L extracts. Graphical abstract Comparison of cleanup methods in the analysis of veterinary Drug Residues in bovine tissues
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comparison of veterinary Drug Residue results in animal tissues by ultrahigh performance liquid chromatography coupled to triple quadrupole or quadrupole time of flight tandem mass spectrometry after different sample preparation methods including use
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Tarun Anumol, Steven J. Lehotay, Joan Stevens, Jerry ZweigenbaumAbstract:Veterinary Drug Residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in Drug Residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the Drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-Residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography–tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 Drugs at regulatory levels of concern in animal tissues. Recently, a new cleanup product called “enhanced matrix removal for lipids” (EMR-L) was commercially introduced that used a unique chemical mechanism to remove lipids from extracts. Furthermore, high-resolution quadrupole–time-of-flight (Q/TOF) for (U)HPLC detection often yields higher selectivity than targeted QQQ analyzers while allowing retroactive processing of samples for other contaminants. In this study, the use of both d-SPE and EMR-L sample preparation and UHPLC-QQQ and UHPLC-Q/TOF analysis methods for shared spiked samples of bovine muscle, kidney, and liver was compared. The results showed that the EMR-L method provided cleaner extracts overall and improved results for several anthelmintics and tranquilizers compared to the d-SPE method, but the EMR-L method gave lower recoveries for certain β-lactam antibiotics. QQQ vs. Q/TOF detection showed similar mixed performance advantages depending on analytes and matrix interferences, with an advantage to Q/TOF for greater possible analytical scope and non-targeted data collection. Either combination of approaches may be used to meet monitoring purposes, with an edge in efficiency to d-SPE, but greater instrument robustness and less matrix effects when analyzing EMR-L extracts.
Rimo Xi - One of the best experts on this subject based on the ideXlab platform.
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review current development of immunoassay for analyzing veterinary Drug Residue in foods and food products
Analytical Letters, 2011Co-Authors: Meng Meng, Rimo XiAbstract:Veterinary Drug Residues in foods and food products have been reported to be harmful for consumer health and must not be permitted in food intended for human consumption. These Drugs include antibiotics, anthelmintics, beta-receptor agonists, and steroids. Immunoassay is recognized as the most powerful screening technique for a large number of different compounds. Because of the rapidity, sensitivity, and cost-effectiveness of this method, numerous immunoassays have already been developed for screening purposes to reduce sample loading for conventional analysis. In this review, the principles and an overview of advanced immunoassays for various veterinary Drugs will be given.
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preparation of anti gatifloxacin antibody and development of an indirect competitive enzyme linked immunosorbent assay for the detection of gatifloxacin Residue in milk
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Chengbiao Zhao, Hongli Ling, Shengxin Lu, Yulan Zhang, Rimo XiAbstract:A polyclonal anti-gatifloxacin antibody has been prepared, and an indirect competitive enzyme-linked immunosorbent assay (cELISA) was developed on the basis of the antibody prepared for the first time. The antibody shows high sensitivity with an IC50 value of 2.6 ppb and excellent specificity with only a minor cross-reaction with lomefloxacin (3.0%) among common (fluoro)quinolones evaluated in this study. The high specificity of the antibody was explained by the molecular structures of related Drugs by comparison with published research. The cELISA test kit developed has a detection limit of 0.05 ppb and could be used as a screening method to detect and regulate illegal use of gatifloxacin in food and food products. The test kit was applied to the detection of milk samples spiked by gatifloxacin. The recovery rates were in the range of 86−106%, whereas the intra- and interassay coefficients of variation were <14.3 and <19.6%, respectively. Keywords: Gatifloxacin; Drug Residue; antibody; immunoassay; cross...
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preparation of polyclonal antibodies to a derivative of 1 aminohydantoin ahd and development of an indirect competitive elisa for the detection of nitrofurantoin Residue in water
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Chengbiao Zhao, Shengxin Lu, Yulan Zhang, Rimo XiAbstract:Nitrofurans are used widely to treat animal diseases and were identified as the major compounds in many worldwide Drug Residue violations. To develop a rapid and convenient detection method to measure the Residue of nitrofurantoin, we designed an immunogen and prepared a polyclonal antibody to develop an immunoassay in this study. The antibodies obtained were characterized by an indirect cELISA method and showed excellent specificity and sensitivity with IC50 of 3.2 ppb and no cross-reaction with most related species and compounds. Considering that nitrofurans often are used illegally to feed animals through drinking water, we measured the Residue of nitrofurantoin in water spiked by the Drug. The recovery rates are in the ranges of 88−103% for interassay and 90−103% for intra-assay. The CVs are in the ranges of 3.1−11.4% for interassay and 2.7−6.2% for intra-assay. The detection limit was determined to be 0.2 ppb. The immunoassay developed in this study is suitable to be used as a screening method to det...
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preparation of anti pefloxacin antibody and development of an indirect competitive enzyme linked immunosorbent assay for detection of pefloxacin Residue in chicken liver
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Shengxin Lu, Chengbiao Zhao, Yulan Zhang, Rimo XiAbstract:Pefloxacin has been increasingly used in veterinary medicine to treat microbial infections. To avoid using a labor-intensive instrumental method to detect the Residue of pefloxacin in food, a simple and convenient indirect competitive enzyme-linked immunosorbent assay method has been developed in this study. The antibody generated from immunogen cationized bovine serum albumin−pefloxacin showed high sensitivity toward pefloxacin with an IC50 value of 6.7 ppb in buffer and was suitable for a screening assay to detect the Residue of pefloxacin in food products. The antibody has been assessed using rapid enzyme immunoassays to exploit its specificity. The antibody prepared shows cross-reactivity with a few other (fluoro)quinolones including fleroxacin (116%), enrofloxacin (88%), and ofloxacin (10%). The assay measured Drug Residue in chicken liver spiked with pefloxacin with an interassay coefficient of variation of 13.6% or less and an intra-assay coefficient of variation of 10.9% or less. The average recov...
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Preparation of anti-pefloxacin antibody and development of an indirect competitive enzyme-linked immunosorbent assay for detection of pefloxacin Residue in chicken liver
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Shengxin Lu, Jingting Liu, Chengbiao Zhao, Yulan Zhang, Wei Liu, Rimo XiAbstract:Pefloxacin has been increasingly used in veterinary medicine to treat microbial infections. To avoid using a labor-intensive instrumental method to detect the Residue of pefloxacin in food, a simple and convenient indirect competitive enzyme-linked immunosorbent assay method has been developed in this study. The antibody generated from immunogen cationized bovine serum albumin-pefloxacin showed high sensitivity toward pefloxacin with an IC50 value of 6.7 ppb in buffer and was suitable for a screening assay to detect the Residue of pefloxacin in food products. The antibody has been assessed using rapid enzyme immunoassays to exploit its specificity. The antibody prepared shows cross-reactivity with a few other (fluoro)quinolones including fleroxacin (116%), enrofloxacin (88%), and ofloxacin (10%). The assay measured Drug Residue in chicken liver spiked with pefloxacin with an interassay coefficient of variation of 13.6% or less and an intra-assay coefficient of variation of 10.9% or less. The average recovery rates at 0.5, 5, 10, 50, and 100 ppb were in the range of 86-106% for interassay and in the range of 87-103% for intra-assay, respectively.
Tarun Anumol - One of the best experts on this subject based on the ideXlab platform.
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Comparison of veterinary Drug Residue results in animal tissues by ultrahigh-performance liquid chromatography coupled to triple quadrupole or quadrupole–time-of-flight tandem mass spectrometry after different sample preparation methods, including us
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Tarun Anumol, Steven J. Lehotay, Joan Stevens, Jerry ZweigenbaumAbstract:Veterinary Drug Residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in Drug Residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the Drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-Residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography–tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 Drugs at regulatory levels of concern in animal tissues. Recently, a new cleanup product called “enhanced matrix removal for lipids” (EMR-L) was commercially introduced that used a unique chemical mechanism to remove lipids from extracts. Furthermore, high-resolution quadrupole–time-of-flight (Q/TOF) for (U)HPLC detection often yields higher selectivity than targeted QQQ analyzers while allowing retroactive processing of samples for other contaminants. In this study, the use of both d-SPE and EMR-L sample preparation and UHPLC-QQQ and UHPLC-Q/TOF analysis methods for shared spiked samples of bovine muscle, kidney, and liver was compared. The results showed that the EMR-L method provided cleaner extracts overall and improved results for several anthelmintics and tranquilizers compared to the d-SPE method, but the EMR-L method gave lower recoveries for certain β-lactam antibiotics. QQQ vs. Q/TOF detection showed similar mixed performance advantages depending on analytes and matrix interferences, with an advantage to Q/TOF for greater possible analytical scope and non-targeted data collection. Either combination of approaches may be used to meet monitoring purposes, with an edge in efficiency to d-SPE, but greater instrument robustness and less matrix effects when analyzing EMR-L extracts. Graphical abstract Comparison of cleanup methods in the analysis of veterinary Drug Residues in bovine tissues
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comparison of veterinary Drug Residue results in animal tissues by ultrahigh performance liquid chromatography coupled to triple quadrupole or quadrupole time of flight tandem mass spectrometry after different sample preparation methods including use
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Tarun Anumol, Steven J. Lehotay, Joan Stevens, Jerry ZweigenbaumAbstract:Veterinary Drug Residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in Drug Residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the Drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-Residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography–tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 Drugs at regulatory levels of concern in animal tissues. Recently, a new cleanup product called “enhanced matrix removal for lipids” (EMR-L) was commercially introduced that used a unique chemical mechanism to remove lipids from extracts. Furthermore, high-resolution quadrupole–time-of-flight (Q/TOF) for (U)HPLC detection often yields higher selectivity than targeted QQQ analyzers while allowing retroactive processing of samples for other contaminants. In this study, the use of both d-SPE and EMR-L sample preparation and UHPLC-QQQ and UHPLC-Q/TOF analysis methods for shared spiked samples of bovine muscle, kidney, and liver was compared. The results showed that the EMR-L method provided cleaner extracts overall and improved results for several anthelmintics and tranquilizers compared to the d-SPE method, but the EMR-L method gave lower recoveries for certain β-lactam antibiotics. QQQ vs. Q/TOF detection showed similar mixed performance advantages depending on analytes and matrix interferences, with an advantage to Q/TOF for greater possible analytical scope and non-targeted data collection. Either combination of approaches may be used to meet monitoring purposes, with an edge in efficiency to d-SPE, but greater instrument robustness and less matrix effects when analyzing EMR-L extracts.
Michel W F Nielen - One of the best experts on this subject based on the ideXlab platform.
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a critical assessment of the performance criteria in confirmatory analysis for veterinary Drug Residue analysis using mass spectrometric detection in selected reaction monitoring mode
Drug Testing and Analysis, 2016Co-Authors: B J A Berendsen, Thijs Meijer, Robin S Wegh, Wesley G Smyth, Armstrong S Hewitt, Leen Van Ginkel, Michel W F NielenAbstract:Besides the identification point system to assure adequate set-up of instrumentation, European Commission Decision 2002/657/EC includes performance criteria regarding relative ion abundances in mass spectrometry and chromatographic retention time. In confirmatory analysis, the relative abundance of two product ions, acquired in selected reaction monitoring mode, the ion ratio should be within certain ranges for confirmation of the identity of a substance. The acceptable tolerance of the ion ratio varies with the relative abundance of the two product ions and for retention time, CD 2002/657/EC allows a tolerance of 5%. Because of rapid technical advances in analytical instruments and new approaches applied in the field of contaminant testing in food products (multi-compound and multi-class methods) a critical assessment of these criteria is justified. In this study a large number of representative, though challenging sample extracts were prepared, including muscle, urine, milk and liver, spiked with 100 registered and banned veterinary Drugs at levels ranging from 0.5 to 100 µg/kg. These extracts were analysed using SRM mode using different chromatographic conditions and mass spectrometers from different vendors. In the initial study, robust data was collected using four different instrumental set-ups. Based on a unique and highly relevant data set, consisting of over 39 000 data points, the ion ratio and retention time criteria for applicability in confirmatory analysis were assessed. The outcomes were verified based on a collaborative trial including laboratories from all over the world. It was concluded that the ion ratio deviation is not related to the value of the ion ratio, but rather to the intensity of the lowest product ion. Therefore a fixed ion ratio deviation tolerance of 50% (relative) is proposed, which also is applicable for compounds present at sub-ppb levels or having poor ionisation efficiency. Furthermore, it was observed that retention time shifts, when using gradient elution, as is common practice nowadays, are mainly observed for early eluting compounds. Therefore a maximum retention time deviation of 0.2 min (absolute) is proposed. These findings should serve as input for discussions on the revision of currently applied criteria and the establishment of a new, globally accepted, criterion document for confirmatory analysis. Copyright © 2016 John Wiley & Sons, Ltd.
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full scan accurate mass selectivity of ultra performance liquid chromatography combined with time of flight and orbitrap mass spectrometry in hormone and veterinary Drug Residue analysis
Journal of the American Society for Mass Spectrometry, 2009Co-Authors: E Van Der Heeft, Y J C Bolck, B Beumer, A W J M Nijrolder, A A M Stolker, Michel W F NielenAbstract:The applicability of ultra-performance liquid chromatography (UPLC) combined with full-scan accurate mass time-of-flight (TOF) and Orbitrap mass spectrometry (MS) to the analysis of hormone and veterinary Drug Residues was evaluated. Extracts from blank bovine hair were fortified with 14 steroid esters. UPLC-Orbitrap MS performed at a resolving power of 60,000 (FWHM) enabled the detection and accurate mass measurement (<3 ppm error) of all 14 steroid esters at low ng/g concentration level, despite the complex matrix background. A 5 ppm mass tolerance window proved to be essential to generate highly selective reconstructed ion chromatograms (RICs) having reduced background from the hair matrix. UPLC-Orbitrap MS at a lower resolving power of 7500 and UPLC-TOFMS at mass resolving power 10,000 failed both to detect all of the steroid esters in hair extracts owing to the inability to mass resolve analyte ions from co-eluting isobaric matrix compounds. In a second application, animal feed extracts were fortified with coccidiostats Drugs at levels ranging from 240 to 1900 ng/g. UPLC-Orbitrap MS conducted at a resolving power of 7500 and 60,000 and UPLC-TOFMS detected all of the analytes at the lowest investigated level. Thanks to the higher analyte-to-matrix background ratio, the utilization of very narrow mass tolerance windows in the RIC was not required. This study demonstrates that even when the targeted sample preparation from conventional LC-MS/MS is applied to UPLC with full-scan accurate mass MS, false compliant (false negative) results can be obtained when the mass resolving power of the MS is insufficient to separate analyte ions from isobaric co-eluting sample matrix ions. The current trend towards more generic and less selective sample preparation is expected to aggravate this issue further.
Joan Stevens - One of the best experts on this subject based on the ideXlab platform.
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Comparison of veterinary Drug Residue results in animal tissues by ultrahigh-performance liquid chromatography coupled to triple quadrupole or quadrupole–time-of-flight tandem mass spectrometry after different sample preparation methods, including us
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Tarun Anumol, Steven J. Lehotay, Joan Stevens, Jerry ZweigenbaumAbstract:Veterinary Drug Residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in Drug Residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the Drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-Residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography–tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 Drugs at regulatory levels of concern in animal tissues. Recently, a new cleanup product called “enhanced matrix removal for lipids” (EMR-L) was commercially introduced that used a unique chemical mechanism to remove lipids from extracts. Furthermore, high-resolution quadrupole–time-of-flight (Q/TOF) for (U)HPLC detection often yields higher selectivity than targeted QQQ analyzers while allowing retroactive processing of samples for other contaminants. In this study, the use of both d-SPE and EMR-L sample preparation and UHPLC-QQQ and UHPLC-Q/TOF analysis methods for shared spiked samples of bovine muscle, kidney, and liver was compared. The results showed that the EMR-L method provided cleaner extracts overall and improved results for several anthelmintics and tranquilizers compared to the d-SPE method, but the EMR-L method gave lower recoveries for certain β-lactam antibiotics. QQQ vs. Q/TOF detection showed similar mixed performance advantages depending on analytes and matrix interferences, with an advantage to Q/TOF for greater possible analytical scope and non-targeted data collection. Either combination of approaches may be used to meet monitoring purposes, with an edge in efficiency to d-SPE, but greater instrument robustness and less matrix effects when analyzing EMR-L extracts. Graphical abstract Comparison of cleanup methods in the analysis of veterinary Drug Residues in bovine tissues
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comparison of veterinary Drug Residue results in animal tissues by ultrahigh performance liquid chromatography coupled to triple quadrupole or quadrupole time of flight tandem mass spectrometry after different sample preparation methods including use
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Tarun Anumol, Steven J. Lehotay, Joan Stevens, Jerry ZweigenbaumAbstract:Veterinary Drug Residues in animal-derived foods must be monitored to ensure food safety, verify proper veterinary practices, enforce legal limits in domestic and imported foods, and for other purposes. A common goal in Drug Residue analysis in foods is to achieve acceptable monitoring results for as many analytes as possible, with higher priority given to the Drugs of most concern, in an efficient and robust manner. The U.S. Department of Agriculture has implemented a multiclass, multi-Residue method based on sample preparation using dispersive solid phase extraction (d-SPE) for cleanup and ultrahigh-performance liquid chromatography–tandem quadrupole mass spectrometry (UHPLC-QQQ) for analysis of >120 Drugs at regulatory levels of concern in animal tissues. Recently, a new cleanup product called “enhanced matrix removal for lipids” (EMR-L) was commercially introduced that used a unique chemical mechanism to remove lipids from extracts. Furthermore, high-resolution quadrupole–time-of-flight (Q/TOF) for (U)HPLC detection often yields higher selectivity than targeted QQQ analyzers while allowing retroactive processing of samples for other contaminants. In this study, the use of both d-SPE and EMR-L sample preparation and UHPLC-QQQ and UHPLC-Q/TOF analysis methods for shared spiked samples of bovine muscle, kidney, and liver was compared. The results showed that the EMR-L method provided cleaner extracts overall and improved results for several anthelmintics and tranquilizers compared to the d-SPE method, but the EMR-L method gave lower recoveries for certain β-lactam antibiotics. QQQ vs. Q/TOF detection showed similar mixed performance advantages depending on analytes and matrix interferences, with an advantage to Q/TOF for greater possible analytical scope and non-targeted data collection. Either combination of approaches may be used to meet monitoring purposes, with an edge in efficiency to d-SPE, but greater instrument robustness and less matrix effects when analyzing EMR-L extracts.
