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Olof Beck - One of the best experts on this subject based on the ideXlab platform.

  • Direct and efficient liquid chromatographic-tandem mass spectrometric method for opiates in urine drug testing – importance of 6-acetylmorphine and reduction of analytes
    Drug Testing and Analysis, 2013
    Co-Authors: Maria Andersson, Nikolai Stephanson, Tommy Terzuoli, Jonatan D. Lindh, Inger Öhman, Olof Beck
    Abstract:

    Opiates comprise a class of abused drugs that is of primary interest in clinical and forensic urine drug testing. Determination of heroin, codeine, or a multi-drug ingestion is complicated since both heroin and codeine can lead to urinary excretion of free and conjugated morphine. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers advantage over gas chromatography-mass spectrometry by simplifying sample preparation but increases the number of analytes. A method based on direct injection of five-fold diluted urine for confirmation of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, Codeine-6-Glucuronide and 6-acetylmorphine was validated using LC-MS/MS in positive electrospray mode monitoring two transitions using selected reaction monitoring. The method was applied for the analysis of 3155 unknown urine samples which were positive for opiates in immunochemical screening. A linear response was observed for all compounds in the calibration curves covering more than three orders of magnitude. Cut off was set to 2 ng/ml for 6-acetylmorphine and 150 ng/ml for the other analytes. 6-Acetylmorphine was found to be effective (sensitivity 82%) in detecting samples as heroin intake. Morphine-3-glucuronide and Codeine-6-Glucuronide was the predominant components of total morphine and codeine, 84% and 93%, respectively. The authors have validated a robust LC-MS/MS method for rapid qualitative and quantitative analysis of opiates in urine. 6-Acetylmorphine has been demonstrated as a sensitive and important parameter for a heroin intake. A possible interpretation strategy to conclude the source of detected analytes was proposed. The method might be further developed by reducing the number of analytes to morphine-3-glucuronide, Codeine-6-Glucuronide and 6-acetylmorphine without compromising test performance. Copyright © 2013 John Wiley & Sons, Ltd.

  • Direct and efficient liquid chromatographic-tandem mass spectrometric method for opiates in urine drug testing – importance of 6-acetylmorphine and reduction of analytes
    Drug testing and analysis, 2013
    Co-Authors: Maria Andersson, Nikolai Stephanson, Tommy Terzuoli, Jonatan D. Lindh, Inger Öhman, Olof Beck
    Abstract:

    Opiates comprise a class of abused drugs that is of primary interest in clinical and forensic urine drug testing. Determination of heroin, codeine, or a multi-drug ingestion is complicated since both heroin and codeine can lead to urinary excretion of free and conjugated morphine. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers advantage over gas chromatography-mass spectrometry by simplifying sample preparation but increases the number of analytes. A method based on direct injection of five-fold diluted urine for confirmation of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, Codeine-6-Glucuronide and 6-acetylmorphine was validated using LC-MS/MS in positive electrospray mode monitoring two transitions using selected reaction monitoring. The method was applied for the analysis of 3155 unknown urine samples which were positive for opiates in immunochemical screening. A linear response was observed for all compounds in the calibration curves covering more than three orders of magnitude. Cut off was set to 2 ng/ml for 6-acetylmorphine and 150 ng/ml for the other analytes. 6-Acetylmorphine was found to be effective (sensitivity 82%) in detecting samples as heroin intake. Morphine-3-glucuronide and Codeine-6-Glucuronide was the predominant components of total morphine and codeine, 84% and 93%, respectively. The authors have validated a robust LC-MS/MS method for rapid qualitative and quantitative analysis of opiates in urine. 6-Acetylmorphine has been demonstrated as a sensitive and important parameter for a heroin intake. A possible interpretation strategy to conclude the source of detected analytes was proposed. The method might be further developed by reducing the number of analytes to morphine-3-glucuronide, Codeine-6-Glucuronide and 6-acetylmorphine without compromising test performance.

  • Evaluation of a direct high-capacity target screening approach for urine drug testing using liquid chromatography–time-of-flight mass spectrometry
    Journal of Chromatography B, 2012
    Co-Authors: Aljona Saleh, Nikolai Stephanson, Ingrid Granelli, Tomas Villen, Olof Beck
    Abstract:

    Abstract In this study a rapid liquid chromatography–time-of-flight mass spectrometry method was developed, validated and applied in order to evaluate the potential of this technique for routine urine drug testing. Approximately 800 authentic patient samples were analyzed for amphetamines (amphetamine and methamphetamine), opiates (morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine and Codeine-6-Glucuronide) and buprenorphines (buprenorphine and buprenorphine-glucuronide) using immunochemical screening assays and mass spectrometry confirmation methods for comparison. The chromatographic application utilized a rapid gradient with high flow and a reversed phase column with 1.8 μm particles. Total analysis time was 4 min. The mass spectrometer operated with an electrospray interface in positive mode with a resolution power of >10,000 at m/z 956. The applied reporting limits were 100 ng/mL for amphetamines and opiates, and 5 ng/mL for buprenorphines, with lower limits of quantification were 2.8–41 ng/mL. Calibration curves showed a linear response with coefficients of correlation of 0.97–0.99. The intra- and interday imprecision in quantification at the reporting limits were

  • electrospray lc ms method with solid phase extraction for accurate determination of morphine codeine and ethylmorphine glucuronides and 6 acetylmorphine in urine
    Journal of Analytical Toxicology, 2007
    Co-Authors: J O Svensson, E. Gustavsson, Maria Andersson, Olof Beck
    Abstract:

    I human urine based on solid-phase extraction (SPE) and electrospray ionization liquid chromatography-mass spectrometry (LC-MS) was validated for use as a confirmation procedure in combination with immunochemical screening for opiates. Three deuterium-labelled analogues were used as internal standards: morphine-3- glucuronide-d3, codeine-d3, and 6-acetylmorphine-d3. Fifty- microliter aliquots of urine were prepared by SPE using 30-mg Oasis HLB cartridges. The chromatographic system consisted of a 2.0 x 100-ram C18 column and the gradient elution buffers used acetonitrile and 25 mmol/L formic acid. The protonated molecular ions were monitored in the selected ion monitoring mode together with one qualifier ion for each analyte. The variability was less than 10% at the reporting limit 30 ng/mL for 6-acetylmorphine and 300 ng/mL for the other analytes. The method was validated by comparison with a reference gas chromatographic (GC)-MS method using authentic urine samples. The two methods agreed completely regarding identified analytes, and for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by GC-MS. This result was to be expected because the free compounds are not measured with the LC-MS method. This study concludes that the presented LC-MS

  • Validation of direct injection electrospray LC-MS/MS for confirmation of opiates in urine drug testing
    Journal of mass spectrometry : JMS, 2007
    Co-Authors: E. Gustavsson, Nikolai Stephanson, Maria Andersson, Olof Beck
    Abstract:

    A method based on the direct injection of diluted urine for the identification and quantification of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, Codeine-6-Glucuronide, ethylmorphine, ethylmorphine-6-glucuronide and 6-acetylmorphine (6AM) in human urine by electrospray ionisation liquid chromatography-tandem mass spectrometry was validated for use as a confirmation procedure in urine drug testing. Four deuterium labelled analogues were used as internal standards: morphine-3-glucuronide-D3, morphine-D3, codeine-D3 and 6AM-D3. Twenty microlitre aliquots of urine were mixed with 80 μl of the internal standard solution in autosampler vials and 10 μl was injected. The chromatographic system consisted of a 2.0 × 100 mm C18 column and the gradient elution buffers used acetonitrile and 25 mmol/l formic acid. Two product ions produced from the protonated molecular ions were monitored in the selected reaction monitoring mode. The intra- and inter-assay variability (coefficient of variation) was below 10% at higher levels for all analytes, but at the reporting limits the variation was above 20% for 6AM, morphine-3-glucuronide and Codeine-6-Glucuronide. Ion suppression occurred early after injection but did not affect the identification and quantification of the analytes in authentic samples. The method was further validated by comparison with a reference gas chromatographic-mass spectrometric method using authentic urine samples. The two methods agreed almost completely (99%) regarding the identified analytes, but for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by gas chromatography-mass spectrometry. We conclude that the presented liquid chromatographic-tandem mass spectrometric method is robust and reliable, and suitable for use as a confirmation method in urine drug testing for opiates Copyright © 2007 John Wiley & Sons, Ltd.

Maria Andersson - One of the best experts on this subject based on the ideXlab platform.

  • Direct and efficient liquid chromatographic-tandem mass spectrometric method for opiates in urine drug testing – importance of 6-acetylmorphine and reduction of analytes
    Drug Testing and Analysis, 2013
    Co-Authors: Maria Andersson, Nikolai Stephanson, Tommy Terzuoli, Jonatan D. Lindh, Inger Öhman, Olof Beck
    Abstract:

    Opiates comprise a class of abused drugs that is of primary interest in clinical and forensic urine drug testing. Determination of heroin, codeine, or a multi-drug ingestion is complicated since both heroin and codeine can lead to urinary excretion of free and conjugated morphine. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers advantage over gas chromatography-mass spectrometry by simplifying sample preparation but increases the number of analytes. A method based on direct injection of five-fold diluted urine for confirmation of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, Codeine-6-Glucuronide and 6-acetylmorphine was validated using LC-MS/MS in positive electrospray mode monitoring two transitions using selected reaction monitoring. The method was applied for the analysis of 3155 unknown urine samples which were positive for opiates in immunochemical screening. A linear response was observed for all compounds in the calibration curves covering more than three orders of magnitude. Cut off was set to 2 ng/ml for 6-acetylmorphine and 150 ng/ml for the other analytes. 6-Acetylmorphine was found to be effective (sensitivity 82%) in detecting samples as heroin intake. Morphine-3-glucuronide and Codeine-6-Glucuronide was the predominant components of total morphine and codeine, 84% and 93%, respectively. The authors have validated a robust LC-MS/MS method for rapid qualitative and quantitative analysis of opiates in urine. 6-Acetylmorphine has been demonstrated as a sensitive and important parameter for a heroin intake. A possible interpretation strategy to conclude the source of detected analytes was proposed. The method might be further developed by reducing the number of analytes to morphine-3-glucuronide, Codeine-6-Glucuronide and 6-acetylmorphine without compromising test performance. Copyright © 2013 John Wiley & Sons, Ltd.

  • Direct and efficient liquid chromatographic-tandem mass spectrometric method for opiates in urine drug testing – importance of 6-acetylmorphine and reduction of analytes
    Drug testing and analysis, 2013
    Co-Authors: Maria Andersson, Nikolai Stephanson, Tommy Terzuoli, Jonatan D. Lindh, Inger Öhman, Olof Beck
    Abstract:

    Opiates comprise a class of abused drugs that is of primary interest in clinical and forensic urine drug testing. Determination of heroin, codeine, or a multi-drug ingestion is complicated since both heroin and codeine can lead to urinary excretion of free and conjugated morphine. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers advantage over gas chromatography-mass spectrometry by simplifying sample preparation but increases the number of analytes. A method based on direct injection of five-fold diluted urine for confirmation of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, Codeine-6-Glucuronide and 6-acetylmorphine was validated using LC-MS/MS in positive electrospray mode monitoring two transitions using selected reaction monitoring. The method was applied for the analysis of 3155 unknown urine samples which were positive for opiates in immunochemical screening. A linear response was observed for all compounds in the calibration curves covering more than three orders of magnitude. Cut off was set to 2 ng/ml for 6-acetylmorphine and 150 ng/ml for the other analytes. 6-Acetylmorphine was found to be effective (sensitivity 82%) in detecting samples as heroin intake. Morphine-3-glucuronide and Codeine-6-Glucuronide was the predominant components of total morphine and codeine, 84% and 93%, respectively. The authors have validated a robust LC-MS/MS method for rapid qualitative and quantitative analysis of opiates in urine. 6-Acetylmorphine has been demonstrated as a sensitive and important parameter for a heroin intake. A possible interpretation strategy to conclude the source of detected analytes was proposed. The method might be further developed by reducing the number of analytes to morphine-3-glucuronide, Codeine-6-Glucuronide and 6-acetylmorphine without compromising test performance.

  • electrospray lc ms method with solid phase extraction for accurate determination of morphine codeine and ethylmorphine glucuronides and 6 acetylmorphine in urine
    Journal of Analytical Toxicology, 2007
    Co-Authors: J O Svensson, E. Gustavsson, Maria Andersson, Olof Beck
    Abstract:

    I human urine based on solid-phase extraction (SPE) and electrospray ionization liquid chromatography-mass spectrometry (LC-MS) was validated for use as a confirmation procedure in combination with immunochemical screening for opiates. Three deuterium-labelled analogues were used as internal standards: morphine-3- glucuronide-d3, codeine-d3, and 6-acetylmorphine-d3. Fifty- microliter aliquots of urine were prepared by SPE using 30-mg Oasis HLB cartridges. The chromatographic system consisted of a 2.0 x 100-ram C18 column and the gradient elution buffers used acetonitrile and 25 mmol/L formic acid. The protonated molecular ions were monitored in the selected ion monitoring mode together with one qualifier ion for each analyte. The variability was less than 10% at the reporting limit 30 ng/mL for 6-acetylmorphine and 300 ng/mL for the other analytes. The method was validated by comparison with a reference gas chromatographic (GC)-MS method using authentic urine samples. The two methods agreed completely regarding identified analytes, and for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by GC-MS. This result was to be expected because the free compounds are not measured with the LC-MS method. This study concludes that the presented LC-MS

  • Validation of direct injection electrospray LC-MS/MS for confirmation of opiates in urine drug testing
    Journal of mass spectrometry : JMS, 2007
    Co-Authors: E. Gustavsson, Nikolai Stephanson, Maria Andersson, Olof Beck
    Abstract:

    A method based on the direct injection of diluted urine for the identification and quantification of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, Codeine-6-Glucuronide, ethylmorphine, ethylmorphine-6-glucuronide and 6-acetylmorphine (6AM) in human urine by electrospray ionisation liquid chromatography-tandem mass spectrometry was validated for use as a confirmation procedure in urine drug testing. Four deuterium labelled analogues were used as internal standards: morphine-3-glucuronide-D3, morphine-D3, codeine-D3 and 6AM-D3. Twenty microlitre aliquots of urine were mixed with 80 μl of the internal standard solution in autosampler vials and 10 μl was injected. The chromatographic system consisted of a 2.0 × 100 mm C18 column and the gradient elution buffers used acetonitrile and 25 mmol/l formic acid. Two product ions produced from the protonated molecular ions were monitored in the selected reaction monitoring mode. The intra- and inter-assay variability (coefficient of variation) was below 10% at higher levels for all analytes, but at the reporting limits the variation was above 20% for 6AM, morphine-3-glucuronide and Codeine-6-Glucuronide. Ion suppression occurred early after injection but did not affect the identification and quantification of the analytes in authentic samples. The method was further validated by comparison with a reference gas chromatographic-mass spectrometric method using authentic urine samples. The two methods agreed almost completely (99%) regarding the identified analytes, but for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by gas chromatography-mass spectrometry. We conclude that the presented liquid chromatographic-tandem mass spectrometric method is robust and reliable, and suitable for use as a confirmation method in urine drug testing for opiates Copyright © 2007 John Wiley & Sons, Ltd.

Marilyn A Huestis - One of the best experts on this subject based on the ideXlab platform.

Lars Slordal - One of the best experts on this subject based on the ideXlab platform.

  • post mortem levels and tissue distribution of codeine codeine 6 glucuronide norcodeine morphine and morphine glucuronides in a series of codeine related deaths
    Forensic Science International, 2016
    Co-Authors: Joachim Frost, Trine N. Løkken, Ivar Skjåk Nordrum, Arne Helland, Lars Slordal
    Abstract:

    Abstract This article presents levels and tissue distribution of codeine, Codeine-6-Glucuronide (C6G), norcodeine, morphine and the morphine metabolites morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in post-mortem blood (peripheral and heart blood), vitreous fluid, muscle, fat and brain tissue in a series of 23 codeine-related fatalities. CYP2D6 genotype is also determined and taken into account. Quantification of codeine, C6G, norcodeine, morphine, M3G and M6G was performed with a validated solid phase extraction LC–MS method. The series comprise 19 deaths (83%) attributed to mixed drug intoxication, 4 deaths (17%) attributed to other causes of death, and no cases of unambiguous monointoxication with codeine. The typical peripheral blood concentration pattern in individual cases was C6G ≫ codeine ≫ norcodeine > morphine, and M3G > M6G > morphine. In matrices other than blood, the concentration pattern was similar, although in a less systematic fashion. Measured concentrations were generally lower in matrices other than blood, especially in brain and fat, and in particular for the glucuronides (C6G, M3G and M6G) and, to some extent, morphine. In brain tissue, the presumed active moieties morphine and M6G were both below the LLOQ (0.0080 mg/L and 0.058 mg/L, respectively) in a majority of cases. In general, there was a large variability in both measured concentrations and calculated blood/tissue concentration ratios. There was also a large variability in calculated ratios of morphine to codeine, C6G to codeine and norcodeine to codeine in all matrices, and CYP2D6 genotype was not a reliable predictor of these ratios. The different blood/tissue concentration ratios showed no systematic relationship with the post-mortem interval. No coherent degradation or formation patterns for codeine, morphine, M3G and M6G were observed upon reanalysis in peripheral blood after storage.

  • A validated method for simultaneous determination of codeine, Codeine-6-Glucuronide, norcodeine, morphine, morphine-3-glucuronide and morphine-6-glucuronide in post-mortem blood, vitreous fluid, muscle, fat and brain tissue by LC-MS.
    Journal of Analytical Toxicology, 2015
    Co-Authors: Joachim Frost, Trine N. Løkken, Wenche Rødseth Brede, Ivar Skjåk Nordrum, Solfrid Hegstad, Lars Slordal
    Abstract:

    The toxicodynamics and, to a lesser degree, toxicokinetics of the widely used opiate codeine remain a matter of controversy. To address this issue, analytical methods capable of providing reliable quantification of codeine metabolites alongside codeine concentrations are required. This article presents a validated method for simultaneous determination of codeine, codeine metabolites Codeine-6-Glucuronide (C6G), norcodeine and morphine, and morphine metabolites morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in post-mortem whole blood, vitreous fluid, muscle, fat and brain tissue by high-performance liquid chromatography mass spectrometry. Samples were prepared by solid-phase extraction. The validated ranges were 1.5–300 ng/mL for codeine, norcodeine and morphine, and 23–4,600 ng/mL for C6G, M3G and M6G, with exceptions for norcodeine in muscle (3 – 300 ng/mL), morphine in muscle, fat and brain (3–300 ng/mL) and M6G in fat (46–4,600 ng/mL). Within-run and between-run accuracy (88.1–114.1%) and precision (CV 0.6–12.7%), matrix effects (CV 0.3–13.5%) and recovery (57.8–94.1%) were validated at two concentration levels; 3 and 150 ng/mL for codeine, norcodeine and morphine, and 46 and 2,300 ng/mL for C6G, M3G and M6G. Freeze– thaw and long-term stability (6 months at 28088C) was assessed, showing no significant changes in analyte concentrations (212 to 18%). The method was applied in two authentic forensic autopsy cases implicating codeine in both therapeutic and presumably lethal concentration levels.

  • Investigation of morphine and morphine glucuronide levels and cytochrome P450 isoenzyme 2D6 genotype in codeine-related deaths
    Forensic Science International, 2012
    Co-Authors: Joachim Frost, Ivar Skjåk Nordrum, Arne Helland, Lars Slordal
    Abstract:

    Abstract Compared to morphine and morphine-6-glucuronide (M6G), codeine and its other major metabolites Codeine-6-Glucuronide and norcodeine have weak affinity to opioid μ-receptors. Analgesic effects of codeine are thus largely dependent on metabolic conversion to morphine by the polymorphic cytochrome P450 isoenzyme 2D6 (CYP2D6). How this relates to toxicity and post-mortem whole blood levels is not known. This paper presents a case series of codeine-related deaths where concentrations of morphine, M6G and morphine-3-glucuronide (M3G), as well as CYP2D6 genotype, are taken into account. Post-mortem toxicological specimens from a total of 1444 consecutive forensic autopsy cases in Central Norway were analyzed. Among these, 111 cases with detectable amounts of codeine in femoral blood were identified, of which 34 had femoral blood concentrations exceeding the TIAFT toxicity threshold of 0.3 mg/L. Autopsy records of these 34 cases were retrieved and reviewed. In the 34 reviewed cases, there was a large variability in individual morphine to codeine concentration ratios (M/C ratios), and morphine levels could not be predicted from codeine concentrations, even when CYP2D6 genotype was known. 13 cases had codeine concentrations exceeding the TIAFT threshold for possibly lethal serum concentrations (1.6 mg/L). Among these, 8 individuals had morphine concentrations below the toxic threshold according to TIAFT (0.15 mg/L). In one case, morphine as well as M6G and M3G concentrations were below the limit of detection. A comprehensive investigation of codeine-related fatalities should, in addition to a detailed case history, include quantification of morphine and morphine metabolites. CYP2D6 genotyping may be of interest in cases with unexpectedly high or low M/C ratios.

Ian R Tebbett - One of the best experts on this subject based on the ideXlab platform.