The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Marilyn A Huestis - One of the best experts on this subject based on the ideXlab platform.
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validation of a lc apci ms ms method for quantification of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine eddp and 2 ethyl 5 methyl 3 3 Diphenylpyraline emdp in infant plasma following protein precipitation
Journal of Chromatography B, 2007Co-Authors: Diaa M Shakleya, Lauren M Jansson, Marilyn A HuestisAbstract:Abstract A validated, quantitative LC–APCI-MS/MS method for methadone, EDDP and EMDP in 200-μL plasma is presented. Specimen preparation was limited to protein precipitation and centrifugation. Chromatographic separation was achieved on a Synergi Hydro-RP 80A (50 mm × 2.0 mm, 4 μm) column with gradient elution. The assay was linear from 1 to 500 ng/mL, with intra- and inter-assay accuracy ≥87.5% and intra- and inter-assay precision
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a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometric method for the quantification of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine eddp and 2 ethyl 5 methyl 3 3 diphenylpyroline emdp in h
Journal of Analytical Toxicology, 2007Co-Authors: Robin E Choo, Lauren M Jansson, Karl B Scheidweiler, Marilyn A HuestisAbstract:This manuscript details a validated liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (LC-APCI-MS-MS) method for the quantification of methadone and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyroline (EMDP) in 0.5 mL human breast milk. Limits of detection were 5 ng/mL for methadone and EDDP, and 10 ng/mL for EMDP. Linearity ranged from 10 to 500 ng/mL for all analytes. Breast milk is a complex biological fluid, necessitating several specimen preparation steps to separate methadone and metabolites from the lipophilic matrix. Recoveries were 66-97% following protein precipitation and solid-phase extraction with minimal matrix effect. Acceptable accuracy (89-101%) and precision (15-20% RSD) were achieved for all analytes. This is the first LC-APCI-MS-MS method for the sensitive and specific detection of methadone, EDDP, and EMDP in human breast milk. The method proved suitable for quantification of methadone and metabolites in breast milk of methadone-maintained opiate-dependent women.
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determination of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine 2 ethyl 5 methyl 3 3 Diphenylpyraline and methadol in meconium by liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry
Journal of Chromatography B, 2005Co-Authors: Robin E Choo, Constance M Murphy, Hendree E Jones, Marilyn A HuestisAbstract:This paper details a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI-MS/MS) method for the quantification of methadone, and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), 2-ethyl-5-methyl-3,3-Diphenylpyraline (EMDP) and methadol in human meconium. Limits of detection (LOD) were determined to be 1.0 ng/g for methadone, EDDP and EMDP and 2.5 ng/g for methadol. The limits of quantitation (LOQ) for methadone, EDDP, EMDP were 5 and 25 ng/g for methadol. Linearity ranged from 5.0 to 500 ng/g. Following solid-phase extraction, no matrix effect was observed. This method proved to be suitable for the quantification of methadone, EDDP and EMDP and the semi-quantitation of methadol in meconium. Literature review revealed no other published LC-APCI-MS/MS method for the detection of methadone and its three main metabolites in meconium specimens.
Robin E Choo - One of the best experts on this subject based on the ideXlab platform.
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a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometric method for the quantification of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine eddp and 2 ethyl 5 methyl 3 3 diphenylpyroline emdp in h
Journal of Analytical Toxicology, 2007Co-Authors: Robin E Choo, Lauren M Jansson, Karl B Scheidweiler, Marilyn A HuestisAbstract:This manuscript details a validated liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (LC-APCI-MS-MS) method for the quantification of methadone and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyroline (EMDP) in 0.5 mL human breast milk. Limits of detection were 5 ng/mL for methadone and EDDP, and 10 ng/mL for EMDP. Linearity ranged from 10 to 500 ng/mL for all analytes. Breast milk is a complex biological fluid, necessitating several specimen preparation steps to separate methadone and metabolites from the lipophilic matrix. Recoveries were 66-97% following protein precipitation and solid-phase extraction with minimal matrix effect. Acceptable accuracy (89-101%) and precision (15-20% RSD) were achieved for all analytes. This is the first LC-APCI-MS-MS method for the sensitive and specific detection of methadone, EDDP, and EMDP in human breast milk. The method proved suitable for quantification of methadone and metabolites in breast milk of methadone-maintained opiate-dependent women.
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determination of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine 2 ethyl 5 methyl 3 3 Diphenylpyraline and methadol in meconium by liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry
Journal of Chromatography B, 2005Co-Authors: Robin E Choo, Constance M Murphy, Hendree E Jones, Marilyn A HuestisAbstract:This paper details a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI-MS/MS) method for the quantification of methadone, and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), 2-ethyl-5-methyl-3,3-Diphenylpyraline (EMDP) and methadol in human meconium. Limits of detection (LOD) were determined to be 1.0 ng/g for methadone, EDDP and EMDP and 2.5 ng/g for methadol. The limits of quantitation (LOQ) for methadone, EDDP, EMDP were 5 and 25 ng/g for methadol. Linearity ranged from 5.0 to 500 ng/g. Following solid-phase extraction, no matrix effect was observed. This method proved to be suitable for the quantification of methadone, EDDP and EMDP and the semi-quantitation of methadol in meconium. Literature review revealed no other published LC-APCI-MS/MS method for the detection of methadone and its three main metabolites in meconium specimens.
Lauren M Jansson - One of the best experts on this subject based on the ideXlab platform.
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validation of a lc apci ms ms method for quantification of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine eddp and 2 ethyl 5 methyl 3 3 Diphenylpyraline emdp in infant plasma following protein precipitation
Journal of Chromatography B, 2007Co-Authors: Diaa M Shakleya, Lauren M Jansson, Marilyn A HuestisAbstract:Abstract A validated, quantitative LC–APCI-MS/MS method for methadone, EDDP and EMDP in 200-μL plasma is presented. Specimen preparation was limited to protein precipitation and centrifugation. Chromatographic separation was achieved on a Synergi Hydro-RP 80A (50 mm × 2.0 mm, 4 μm) column with gradient elution. The assay was linear from 1 to 500 ng/mL, with intra- and inter-assay accuracy ≥87.5% and intra- and inter-assay precision
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a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometric method for the quantification of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine eddp and 2 ethyl 5 methyl 3 3 diphenylpyroline emdp in h
Journal of Analytical Toxicology, 2007Co-Authors: Robin E Choo, Lauren M Jansson, Karl B Scheidweiler, Marilyn A HuestisAbstract:This manuscript details a validated liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (LC-APCI-MS-MS) method for the quantification of methadone and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyroline (EMDP) in 0.5 mL human breast milk. Limits of detection were 5 ng/mL for methadone and EDDP, and 10 ng/mL for EMDP. Linearity ranged from 10 to 500 ng/mL for all analytes. Breast milk is a complex biological fluid, necessitating several specimen preparation steps to separate methadone and metabolites from the lipophilic matrix. Recoveries were 66-97% following protein precipitation and solid-phase extraction with minimal matrix effect. Acceptable accuracy (89-101%) and precision (15-20% RSD) were achieved for all analytes. This is the first LC-APCI-MS-MS method for the sensitive and specific detection of methadone, EDDP, and EMDP in human breast milk. The method proved suitable for quantification of methadone and metabolites in breast milk of methadone-maintained opiate-dependent women.
Karl B Scheidweiler - One of the best experts on this subject based on the ideXlab platform.
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a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometric method for the quantification of methadone 2 ethylidene 1 5 dimethyl 3 3 diphenylpyrrolidine eddp and 2 ethyl 5 methyl 3 3 diphenylpyroline emdp in h
Journal of Analytical Toxicology, 2007Co-Authors: Robin E Choo, Lauren M Jansson, Karl B Scheidweiler, Marilyn A HuestisAbstract:This manuscript details a validated liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (LC-APCI-MS-MS) method for the quantification of methadone and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyroline (EMDP) in 0.5 mL human breast milk. Limits of detection were 5 ng/mL for methadone and EDDP, and 10 ng/mL for EMDP. Linearity ranged from 10 to 500 ng/mL for all analytes. Breast milk is a complex biological fluid, necessitating several specimen preparation steps to separate methadone and metabolites from the lipophilic matrix. Recoveries were 66-97% following protein precipitation and solid-phase extraction with minimal matrix effect. Acceptable accuracy (89-101%) and precision (15-20% RSD) were achieved for all analytes. This is the first LC-APCI-MS-MS method for the sensitive and specific detection of methadone, EDDP, and EMDP in human breast milk. The method proved suitable for quantification of methadone and metabolites in breast milk of methadone-maintained opiate-dependent women.
Sara R Jones - One of the best experts on this subject based on the ideXlab platform.
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effects of the histamine h1 receptor antagonist and benztropine analog Diphenylpyraline on dopamine uptake locomotion and reward
European Journal of Pharmacology, 2012Co-Authors: Erik B Oleson, Jill J Harp, Mark J Ferris, Rodrigo A Espana, Sara R JonesAbstract:Diphenylpyraline hydrochloride (DPP) is an internationally available antihistamine that produces therapeutic antiallergic effects by binding to histamine H1 receptors. The complete neuropharmacological and behavioral profile of DPP, however, remains uncharacterized. Here we describe studies that suggest DPP may fit the profile of a potential agonist replacement medication for cocaine addiction. Aside from producing the desired histamine reducing effects, many antihistamines can also elicit psychomotor activation and reward, both of which are associated with increased dopamine concentrations in the nucleus accumbens (NAc). The primary aim of this study was to investigate the potential ability of DPP to inhibit the dopamine transporter, thereby leading to elevated dopamine concentrations in the NAc in a manner similar to cocaine and other psychostimulants. The psychomotor activating and rewarding effects of DPP were also investigated. For comparative purposes cocaine, a known dopamine transporter inhibitor, psychostimulant and drug of abuse, was used as a positive control. As predicted, both cocaine (15 mg/kg) and an equimolar dose of DPP (14 mg/kg) significantly inhibited dopamine uptake in the NAc in vivo and produced locomotor activation, although the time-course of pharmacological effects of the two drugs was different. In comparison to cocaine, DPP showed a prolonged effect on dopamine uptake and locomotion. Furthermore, cocaine, but not DPP, produced significant conditioned place preference, a measure of drug reward. The finding that DPP functions as a potent dopamine uptake inhibitor without producing significant rewarding effects suggests that DPP merits further study as a potential candidate as an agonist pharmacotherapy for cocaine addiction.
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Diphenylpyraline a histamine h1 receptor antagonist has psychostimulant properties
European Journal of Pharmacology, 2005Co-Authors: G B Lapa, Tiffany A Mathews, Jill J Harp, Evgeny A Budygin, Sara R JonesAbstract:Abstract Diphenylpyraline hydrochloride (DPP) is used clinically as an antihistamine drug, but its neurobiological effects are not completely understood. Voltammetry and microdialysis were used to investigate potential actions of DPP on the dopamine system. Voltammetric monitoring of dopamine signals in mouse nucleus accumbens slices showed that DPP (10 μM) markedly inhibited dopamine uptake. There was a 20-fold increase in apparent Km for dopamine uptake, while Vmax was unchanged. Microdialysis experiments demonstrated that DPP (5 mg/kg, i.p.) elevated extracellular dopamine levels (∼200%) in mouse nucleus accumbens. DPP (5 and 10 mg/kg) also induced locomotor activation. All of the effects of DPP were comparable with those of cocaine. Taken together, these results indicate that DPP acts as a competitive dopamine transporter inhibitor similar to cocaine.