Research Topics
| B K MatuszewskiSummaryAffiliation: Merck Research Laboratories Country: USA Publications
|
Detail Information
Publications
Strategies for the assessment of matrix effect in quantitative bioanalytical methods based on HPLC-MS/MSB K Matuszewski
Merck Research Laboratories, West Point, Pennsylvania 19486, USA
Anal Chem 75:3019-30. 2003..It was demonstrated that, for the investigational drug under study, the matrix effect was clearly observed when ISP interface was utilized but it was absent when the HN interface was employed...- Determination of risedronate in human urine by column-switching ion-pair high-performance liquid chromatography with ultraviolet detectionP T Vallano
Department of Drug Metabolism, WP 75 200 West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 794:23-33. 2003..Inter-day precision for quality controls assayed over a 3-week period was better than 5%, while inter-day accuracy was within 90% of nominal. The assay was employed to analyze samples collected during a clinical pharmacokinetics study... - Isolation and structural characterization of the photolysis products of etoricoxibC Z Matthews
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA, USA
Pharmazie 59:913-9. 2004..The results of these experiments indicate that etoricoxib undergoes a photocyclization reaction when irradiated with UV light (254 nm), leading to the formation of two major isomeric photocyclization products... - Determination of L-756 423, a novel HIV protease inhibitor, in human plasma and urine using high-performance liquid chromatography with fluorescence detectionM J Rose
Merck Research Laboratories, Department of Drug Metabolism, West Point, PA 19486, USA
J Chromatogr B Biomed Sci Appl 732:425-35. 1999..Bovine serum albumin (0.5%) was used as an additive to urine to prevent precipitation of L-756 423 during the storage of clinical samples. The assay was used in support of human clinical trials... - High-throughput, semi-automated determination of a cyclooxygenase II inhibitor in human plasma and urine using solid-phase extraction in the 96-well format and high-performance liquid chromatography with post-column photochemical derivatization-fluorescenC Z Matthews
Merck Research Laboratories, Department of Drug Metabolism, West Point, PA 19486, USA
J Chromatogr B Biomed Sci Appl 751:237-46. 2001..The precision and accuracy of the semi-automated procedure were comparable to the manual procedure. Over 5000 clinical samples have been analyzed successfully using these methods... - Monolithic silica liquid chromatography columns for the determination of cyclooxygenase II inhibitors in human plasmaP T Vallano
Merck Research Laboratories, Department of Drug Metabolism, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 779:249-57. 2002..The results of experiments aimed at evaluating the ruggedness and reproducibility of monolithic columns employed in bioanalytical methods are presented... - Determination of dextromethorphan and its metabolite dextrorphan in human urine using high performance liquid chromatography with atmospheric pressure chemical ionization tandem mass spectrometry: a study of selectivity of a tandem mass spectrometric assaM L Constanzer
Merck Research Laboratories, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 816:297-308. 2005..The need for careful assessment of selectivity of the HPLC-MS/MS assay in the presence of metabolites, and the assessment of matrix effect, are emphasized... - Mechanistic studies on the reversible metabolism of rofecoxib to 5-hydroxyrofecoxib in the rat: evidence for transient ring opening of a substituted 2-furanone derivative using stable isotope-labeling techniquesT A Baillie
Department of Drug Metabolism, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
Drug Metab Dispos 29:1614-28. 2001..This sequence represents a novel form of enterohepatic recycling and reflects the susceptibility of 5-hydroxyrofecoxib, as well as rofecoxib itself, to reversible 2-furanone ring opening under in vivo conditions... - Determination of the HIV integrase inhibitor, MK-0518 (raltegravir), in human plasma using 96-well liquid-liquid extraction and HPLC-MS/MSS A Merschman
Department of Drug Metabolism, Merck Research Laboratories, WP75B 300, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 857:15-24. 2007..1% or less. The plasma QC samples were demonstrated to be stable for up to 23 months at -20 degrees C. The method described has been used to support over 18 clinical studies during Phase I through III of clinical development... - High-throughput simultaneous determination of the HIV protease inhibitors indinavir and L-756423 in human plasma using semi-automated 96-well solid phase extraction and LC-MS/MSM J Rose
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
J Pharm Biomed Anal 24:291-305. 2000..0, 2.5, and 3.3%, respectively. The validated assay was used in support of human clinical trials... - Disposition and pharmacokinetics of the antimigraine drug, rizatriptan, in humansK P Vyas
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
Drug Metab Dispos 28:89-95. 2000..The absorption of rizatriptan was approximately 90%, but it experienced a moderate first-pass effect, resulting in a bioavailability estimate of 47%... - Determination of efavirenz, a selective non-nucleoside reverse transcriptase inhibitor, in human plasma using HPLC with post-column photochemical derivatization and fluorescence detectionC Z Matthews
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
J Pharm Biomed Anal 28:925-34. 2002..The quantitative method has been successfully utilized to support a study in which a possible drug interaction between co-administered HIV protease inhibitors and efavirenz was evaluated... - Quantitative liquid chromatographic and tandem mass spectrometric determination of vitamin D3 in human serum with derivatization: a comparison of in-tube LLE, 96-well plate LLE and in-tip SPMEW Xie
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 879:1457-66. 2011..1 mL of human serum required. Comparisons were made among three different methods, including precision and accuracy, sample throughput, recovery and matrix effects... - Determination of a cyclooxygenase II inhibitor in human plasma by capillary gas chromatography with mass spectrometric detectionJ D Y Dru
Department of Drug Metabolism, Merck Research Laboratories, Merck and Co Inc, P O Box 4, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 805:21-5. 2004..The accuracy for I in human plasma was 91-112% and the recovery of I and II was greater than 70% at all concentrations within both standard curve ranges. The details of the assay methodology are presented... - Improved procedure for the the determination of rofecoxib in human plasma involving 96-well solid-phase extraction and fluorescence detectionC Z Matthews
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
J Chromatogr A 949:83-9. 2002..Assay throughput was improved by a factor of three as compared to previously described methods. The method was partially automated using a combination of a Packard Multi-Probe liquid handling system and a TomTec Quadra 96 workstation... - Assessment of the in-vivo stereochemical integrity of aprepitant based on the analysis of human plasma samples via high-performance liquid chromatography with mass spectrometric detectionW F Kline
Merck Research Laboratories, Department of Drug Metabolism, West Point, PA 19486, USA
Biomed Chromatogr 19:513-7. 2005.... - Effect of the sample matrix on the determination of indinavir in human urine by HPLC with turbo ion spray tandem mass spectrometric detectionI Fu
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
J Pharm Biomed Anal 18:347-57. 1998.... - Simultaneous determination of Aprepitant and two metabolites in human plasma by high-performance liquid chromatography with tandem mass spectrometric detectionC M Chavez-Eng
Merck and Co Inc, WP42 208, Merck Research Laboratories, P O Box 4, West Point, PA 19486, USA
J Pharm Biomed Anal 35:1213-29. 2004.... - Determination of a novel substance P inhibitor in human plasma by high-performance liquid chromatography with atmospheric pressure chemical ionization mass spectrometric detection using single and triple quadrupole detectorsM L Constanzer
Merck Research Laboratories, Sumneytown Pike, WP75A 303, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 807:243-50. 2004..Both instruments were used successfully to support numerous clinical trials of Aprepitant... - Determination of an investigational HIV integrase inhibitor in human plasma using high performance liquid chromatography with tandem mass spectrometric detectionP T Vallano
Bioanalytical Laboratory, Mylan Pharmaceuticals Inc, 3711 Collins Ferry Road, Morgantown, WV 26505, USA
J Chromatogr B Analyt Technol Biomed Life Sci 820:69-76. 2005..Inter-day accuracy and precision results for quality control samples run over a 3-month period alongside clinical samples showed mean accuracies of within 6% of nominal and precision better than 3.5% C.V... - Determination of an endothelin receptor antagonist in rat plasma by radioimmunoassayS Yuan
Department of Drug Metabolism, WP 75A 203, Merck Research Laboratories, West Point, PA 19486, USA
J Pharm Biomed Anal 34:391-7. 2004..This direct assay, using 50 microl of rat plasma is sensitive (0.4 ng/ml), without matrix interference, and has sufficient sensitivity, specificity, accuracy and precision for the analysis of dosed rat plasma samples... - Development and implementation of an electrochemiluminescence immunoassay for the determination of an angiogenic polypeptide in dog and rat plasmaA S Yuan
Merck Research Laboratories, WP75A 203, West Point, PA 19486, USA
J Pharm Biomed Anal 33:719-24. 2003..The drug is then sandwiched with a ruthenium chelated second antibody. The assay demonstrates good accuracy and reproducibility at plasma concentration of 0.5 ng/ml... - Simultaneous determination of unlabeled and carbon-13-labeled etoricoxib, a new cyclooxygenase-2 inhibitor, in human plasma using HPLC-MS/MSM J Rose
Merck Research Laboratories, Department of Drug Metabolism, West Point, Pennsylvania 19486, USA
J Pharm Sci 91:405-16. 2002..Within-batch precision and accuracy for the quantitation of (13)C(6)-etoricoxib over the range of 0.5 to 250 ng/mL were 8.3% RSD or less and within 2.3%, respectively. The validated assay was used in support of human clinical trials... - Simultaneous determination of omeprazole and 5'-hydroxyomeprazole in human plasma by liquid chromatography-tandem mass spectrometryE J Woolf
Merck Research Laboratories, Department of Drug Metabolism, West Point, PA 19486, USA
J Chromatogr A 828:229-38. 1998..The assay was used to determine the cytochrome P450 2C19 phenotype of subjects participating in clinical trials of compounds under development... - Comparison of solid-phase microextraction and liquid-liquid extraction in 96-well format for the determination of a drug compound in human plasma by liquid chromatography with tandem mass spectrometric detectionW Xie
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA, USA
J Pharm Biomed Anal 45:599-608. 2007.... - Elimination of autosampler carryover in a bioanalytical HPLC-MS/MS method: a case studyP T Vallano
Merck Research Laboratories, Department of Drug Metabolism, Mail Stop, WP 75 200, West Point, PA 19486, USA
J Pharm Biomed Anal 36:1073-8. 2005..The susceptibility of the HPLC system to carryover was demonstrated to depend on the absolute sensitivity of the detection method and the mass of analyte injected at the assay lower limit of quantitation (LLOQ)... - Standard line slopes as a measure of a relative matrix effect in quantitative HPLC-MS bioanalysisB K Matuszewski
Merck Research Laboratories, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 830:293-300. 2006.... - High-performance liquid chromatographic-tandem mass spectrometric evaluation and determination of stable isotope labeled analogs of rofecoxib in human plasma samples from oral bioavailability studiesC M Chavez-Eng
Merck Research Laboratories, West Point, PA 19486, USA
J Chromatogr B Analyt Technol Biomed Life Sci 767:117-29. 2002..The assay was utilized to support the clinical BA study in which oral doses of I were administered together with an i.v. dose of II to determine the oral BA of rofecoxib at 12.5- and 25-mg doses... - The identification of three human metabolites of a peptide-doxorubicin conjugate using HPLC-MS-MS in positive and negative ionization modesR B Desai
Merck Research Laboratories, Sumneytown Pike, West Point, PA 19486, USA
J Chromatogr Sci 42:317-22. 2004..Simultaneous fluorescence and MS detection experiments confirm that the peaks observed in the HPLC-fluorescence chromatograms of plasma extracts correspond to each of the five metabolites (II-VI)... - Determination of fexofenadine in human plasma using 96-well solid phase extraction and HPLC with tandem mass spectrometric detectionI Fu
Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
J Pharm Biomed Anal 35:837-46. 2004..The method was found to be suitable for the analysis of human plasma samples obtained 24 h following the administration of a single 60 mg dose of fexofenadine... - Characterization of the solubility of a poorly soluble hydroxylated metabolite in human urine and its implications for potential renal toxicityS A Merschman
Sheila A Merschman, Merck Research Laboratories, Department of Drug Metabolism, West Point, PA 19486, USA
Pharmazie 60:359-63. 2005..Consequently, the results of these studies have placed restrictions on the dose that could be administered during clinical development of this compound... - Determination of an echinocandin, MK-0991, in mammalian plasma by radioimmunoassayA S Yuan
Department of Drug Metabolism, WP75A 203, Merck Research Laboratories, West Point, PA 19486, USA
J Pharm Biomed Anal 25:811-20. 2001..The assay demonstrates good accuracy and reproducibility at plasma concentration down to 10 ng/ml. The specificity of the RIA method was confirmed by cross-validating against an established HPLC method...