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Multiple-reaction Monitoring (multiple-reaction + monitoring)

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Chemistry100%

Terms modified by Multiple-reaction Monitoring

  • multiple-reaction monitoring mode
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    Selected Abstracts

    A semi-automated solid-phase extraction liquid chromatography/tandem mass spectrometry method for the analysis of tetrahydrocannabinol and metabolites in whole blood,

    RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 17 2009
    Eshwar Jagerdeo
    Marijuana is one of the most commonly abused illicit substances in the USA, making cannabinoids important to detect in clinical and forensic toxicology laboratories. Historically, cannabinoids in biological fluids have been derivatized and analyzed by gas chromatography/mass spectrometry (GC/MS). There has been a gradual shift in many laboratories towards liquid chromatography/mass spectrometry (LC/MS) for this analysis due to its improved sensitivity and reduced sample preparation compared with GC/MS procedures. This paper reports a validated method for the analysis of ,9 -tetrahydrocannabinol (THC) and its two main metabolites, 11-nor-9-carboxy-,9 -tetrahydrocannabinol (THC-COOH) and 11-hydroxy-,9 -tetrahydrocannabinol (THC-OH), in whole blood samples. The method has also been validated for cannabinol (CBD) and cannabidiol (CDN), two cannabinoids that were shown not to interfere with the method. This method has been successfully applied to samples both from living people and from deceased individuals obtained during autopsy. This method utilizes online solid-phase extraction (SPE) with LC/MS. Pretreatment of samples involves protein precipitation, sample concentration, ultracentrifugation, and reconstitution. The online SPE procedure was developed using Hysphere C8-EC sorbent. A chromatographic gradient with an Xterra MS C18 column was used for the separation. Four multiple-reaction monitoring (MRM) transitions were monitored for each analyte and internal standard. Linearity generally fell between 2 and 200,ng/mL. The limits of detection (LODs) ranged from 0.5 to 3,ng/mL and the limits of quantitation (LOQs) ranged from 2 to 8,ng/mL. The bias and imprecision were determined using a simple analysis of variance (ANOVA: single factor). The results demonstrate bias as <7%, and imprecision as <9%, for all components at each quantity control level. Published in 2009 by John Wiley & Sons, Ltd. [source]

    Pharmacokinetic measurements of IDN 5390 using electrospray ionization tandem mass spectrometry: structure characterization and quantification in dog plasma

    RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 24 2005
    Liguo Song
    In this report, electrospray ionization tandem mass spectrometry (ESI-MS/MS) for a pharmacokinetic study of IDN 5390, a novel C- seco taxane derivative, which is under preclinical evaluation, has been investigated. Our results showed that IDN 5390 and other taxanes including paclitaxel and IDN 5109 could ionize well in not only positive-, but also in negative-ion mode. Under collision-induced dissociation (CID) conditions, these compounds could fragment into similar M- (molecular), T- (taxane ring) and S- (side chain) series ions. In positive-ion ESI, the formation of both T- and S-series ions involved the breaking of the C-13 ester bond. In negative-ion ESI, however, while the formation mechanism of S-series ions remained the same, the breaking of the C-1, carboxylic ester bond resulted in T-series ions. At optimum collision energy (CE) values, M-, T- and S-series ions of IDN 5390 in both positive- and negative-ion ESI-MS/MS spectra had good intensity. This phenomenon makes both positive- and negative-ion ESI-MS/MS good methods for IDN 5390 metabolite structural characterization, i.e. to reveal the location of modification groups in IDN 5390 metabolites versus IDN 5390 either on the side chain or the taxane ring. A liquid chromatography (LC)/ESI-MS/MS method using the multiple-reaction monitoring (MRM) technique was thereafter developed to quantify IDN 5390 in dog plasma using paclitaxel as internal standard. The method was validated using a concentration range between 5 and 1000,ng/mL and had a limit of detection of 1,ng/mL. The inter-day %CV (%coefficient of variation) of the calibration standards ranged between 4.36 and 9.64%, the intra-day %CV of the calibration standards between 0.61 and 13.44%, and the mean % accuracy of the quality control samples at the low, middle and high end of the concentration curves were 12.5, 6.8 and 9.6%, respectively. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Development and validation of UPLC-MS/MS method for simultaneous determination of gestodene and ethinyl estradiol in rat plasma

    BIOMEDICAL CHROMATOGRAPHY, Issue 2 2010
    Zhili Xiong
    Abstract A selective and sensitive ultra-performance liquid chromatography method with tandem mass spectrometric detection for simultaneous determination of gestodene (GES) and ethinyl estradiol (EE) in rat plasma was developed and validated. GES, EE and the internal standard, norgestrel, were extracted with ethyl acetate, derivatized (EE only) with dansyl chloride and then back-extracted into diethyl ether-hexane (2:1, v/v). The separation was performed on an ACQUITY UPLCÔ BEH C18 column with gradient elution using mobile phase consisting of acetonitrile and water (both containing 0.1% formic acid). The detection was carried out by means of electrospray ionization (ESI) mass spectrometry in positive ion mode with multiple-reaction monitoring. Calibration curves of GES and EE were linear (r2,,,0.99) over the concentration ranges 1.59,159 and 0.196,78.4,ng/mL, respectively. The intra- and inter-day precisions were not more than 6.9 and 12.9% for GES and 10.6 and 9.0% for EE, and the accuracies were ,2.5,8.0% for GES, and ,7.2,0.19% for EE, respectively. The method herein described was superior to previous methods and was applicable to the pharmacokinetic study of GES and EE in rats. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Bioanalytical LC-MS/MS method validation for plasma determination of topiramate in healthy Indian volunteers

    BIOMEDICAL CHROMATOGRAPHY, Issue 11 2009
    Dipanjan Goswami
    Abstract A LC-MS/MS method for plasma topiramate analysis is delineated involving least number of healthy volunteers. Topiramate and amlodipine internal standard (IS) were extracted by simple centrifuge-coupled solid-phase extraction and reverse-phase chromatographic separation was performed on an Ascentis C18 column. Turbo-spray negative-ion mode multiple-reaction monitoring was selected for mass pair detection at m/z 338.3 , 78.0 and m/z 407.3 , 295.5 for analyte and IS respectively. The method showed a dynamic linearity range from 10.4 to 2045.0 ng/mL, lower limit of quantitation achieved at 10.4 ng/mL and finally a mass spectrometric total run time of within 2.5 min for human sample analysis. Bioequivalence was assessed successfully using this fully validated method on 16 fasted Indian male subjects with 25 mg topiramate tablet administration. An appropriate study design describes plasma samples collection up to 216 h post dose in two periods, separated by a 28 day washout period. The challenge of half-life matching for test and reference drug was achieved with 73.43 ± 9.68 and 73.06 ± 14.03 h, respectively, and intra-subject coefficient of variation achieved within 11% for AUCs and Cmax evaluated by non-compartmental pharmacokinetic analysis. The results of LCMS topiramate complete method validation supported by pharmacokinetic study have not been published before, and are presented and discussed for the first time in this article. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Identification and quantification of two antihepatotoxic coumarinolignoids cleomiscosin A and cleomiscosin B in the seeds of Cleome viscosa using liquid chromatography,tandem mass spectrometry

    BIOMEDICAL CHROMATOGRAPHY, Issue 4 2009
    Sunil K. Chattopadhyay
    Abstract A sensitive liquid chromatography/electrospray ionization tandem mass spectrometric (LC/ESI-MS/MS) method was developed for the identification and quantification of two antihepatotoxic coumarinolignoids cleomiscosin A and cleomiscosin B in different extracts of the seeds of Cleome viscosa. The separation of cleomiscosin A and cleomiscosin B was achieved on an RP18 column using a solvent system consisting of a mixture of acetonitrile,methanol (1:2, v/v) and acetonitrile,water,formic acid (5:95:0.3, v/v) as a mobile phase in a gradient elution mode. A multiple-reaction monitoring (MRM) method was developed for quantification of cleomiscosin A and cleomiscosin B in the seed extracts of Cleome viscosa. On the basis of signal-to-noise ratio of 3, the limit of detection in MRM mode for cleomiscosin A and cleomiscosin B were 1.0 and 4.0 ng/mL respectively. The method was validated in terms of linearity, accuracy and precision for 6 days. The method developed was found to be useful for identification and quantification of cleomiscosin A and cleomiscosin B in the different extracts of the seeds of Cleome viscosa. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Simultaneous determination and pharmacokinetic study of oxymatrine and matrine in beagle dog plasma after oral administration of Kushen formula granule, oxymatrine and matrine by LC-MS/MS

    BIOMEDICAL CHROMATOGRAPHY, Issue 8 2007
    Yiqi Wang
    Abstract A rapid, specific and sensitive LC-MS/MS method was developed for the determination of oxymatrine (OMT) and matrine (MT) in beagle dog plasma. The method was applied to study the pharmacokinetics of OMT and MT after oral administration of OMT, MT and Kushen formula granule (KFG) containing equivalent amounts of OMT and MT in a three-period crossover design. The analysis was carried out on an Acquity UPLCÔ BEH C18 column by linear gradient elution with 0.01% acetic acid,water,methanol as mobile phase. Detection was by positive ion electrospray ionization (ESI) mass spectrometry with multiple-reaction monitoring (MRM). Linear calibration curves were both obtained over the concentration range 15,2000 ng/mL, with a limit of quantification of 15 ng/mL. The matrix effect was minimized. The intra- and inter-day precisions (RSDs) were less than 12.4 and 14.7%, respectively, and the accuracy (RE) was from ,2.1 to 2.7%. The validated method was used to determine the concentration,time profiles of OMT and MT. The results indicated that the absorption of OMT and MT after oral administration of KFG was significantly greater than that after oral administration of pure components. Copyright © 2007 John Wiley & Sons, Ltd. [source]