The Experts below are selected from a list of 162 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.
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.
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.
S Walker - One of the best experts on this subject based on the ideXlab platform.
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reliability of Veterinary Drug Residue confirmation high resolution mass spectrometry versus tandem mass spectrometry
Analytica Chimica Acta, 2015Co-Authors: Anton Kaufmann, S Walker, Patrick Butcher, Kathryn Maden, Mirjam WidmerAbstract:Abstract Confirmation of suspected Residues has been a long time domain of tandem triple quadrupole mass spectrometry (QqQ). The currently most widely used confirmation strategy relies on the use of two selected reaction monitoring signals (SRM). The details of this confirmation procedure are described in detail in the Commission Decision 93/256/EC (CD). On the other hand, high resolution mass spectrometry (HRMS) is nowadays increasingly used for trace analysis. Yet its utility for confirmatory purposes has not been well explored and utilized, since established confirmation strategies like the CD do not yet include rules for modern HRMS technologies. It is the focus of this paper to evaluate the likelihood of false positive and false negative confirmation results, when using a variety of HRMS based measurement modes as compared to conventional QqQ mass spectrometry. The experimental strategy relies on the chromatographic separation of a complex blank sample (bovine liver extract) and the subsequent monitoring of a number of dummy transitions respectively dummy accurate masses. The term “dummy” refers to precursor and derived product ions (based on a realistic neutral loss) whose elemental compositions (C x H y N z O d Cl e ) were produced by a random number generator. Monitoring a large number of such hypothetical SRM’s, or accurate masses inevitably produces a number of mass traces containing chromatographic peaks (false detects) which are caused by eluting matrix compounds. The number and intensity of these peaks were recorded and standardized to permit a comparison among the two employed MS technologies. QqQ performance (compounds which happen to produce a response in two SRM traces at identical retention time) was compared with a number of different HRMS 1 and HRMS 2 detection based modes. A HRMS confirmation criterion based on two full scans (an unfragmented and an all ion fragmented) was proposed. Compared to the CD criteria, a significantly lower probability of false positive and false negative findings is obtained by utilizing this criterion.
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post run target screening strategy for ultra high performance liquid chromatography coupled to orbitrap based Veterinary Drug Residue analysis in animal urine
Journal of Chromatography A, 2013Co-Authors: A Kaufmann, S WalkerAbstract:Abstract The performance of liquid chromatography coupled to high resolution mass spectrometry (LC–HRMS) post-run target screening for Veterinary Drug Residue analysis (sulfonamides, tetracyclines and quinolones) in animal urine has been critically evaluated. It was found that retention time information still remains an essential information and that accurate masses together with relative isotopic abundance data alone are not sufficient for many Residue applications. Post-run target screening requires the careful setting of parameters to achieve near zero false negative (above a defined threshold level) and a manageable numbers of false positive findings. HRMS offers many possibilities for the reduction of false positives (e.g. isotopic ratio, isotopic fine structure, exact mass of fragment ions). However, the successful use of such tools requires a sufficient ion intensity. This is often not available when trace level compounds are to be detected. Nevertheless, the proposed method is sufficiently sensitive to detect the Veterinary Drugs at the relevant concentration levels in urine. This means that the approach is well suited to significantly reduce the number of corresponding meat samples which have to be analyzed in a final step for the regulatory relevant quantification of Residue levels in meat. The semi-quantitative screening of many samples for a large number of analytes within a short period of time requires the availability of software tools which provide fast and reliable answers.
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.
