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Philip Timmerman
No abstract text is available yet for this article.
November 13, 2018: Bioanalysis
Faye Vazvaei, Philip Timmerman
No abstract text is available yet for this article.
November 13, 2018: Bioanalysis
Sebastiano Barco, Carmen Fucile, Luca Manfredini, Elisa De Grandis, Marcella Gherzi, Antonietta Martelli, Gino Tripodi, Francesca Mattioli, Giuliana Cangemi
AIM: Monitoring of blood levels of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) is necessary for optimization of administration of medical cannabis. We describe the validation of a ultra-HPLC-MS/MS method for quantifying THC and CBD from plasma and decoctions and its application for therapeutic drug monitoring.Materials & methods: Analyses were performed by using a TSQ Quantiva™ Triple Quadrupole coupled to a Ultimate 3000 UHPLC system with atmospheric pressure chemical ionization after sample preparation with a straightforward method with deuterated internal standards...
November 6, 2018: Bioanalysis
Mohsin Ali, Stephanie Läer, Bjoern B Burckhardt
AIM: Intentional and accidental drug intoxication as well as medication adherence require sensitive and reliable analytical screening methods. Such methods are often lacking in children and adults, therefore, a reliable analytical method has been developed by using low plasma volume. MATERIALS & METHODS: Sample preparation from plasma was achieved by solid-phase extraction process. LC-MS in positive ion mode was performed using X-select CSH™ C18 column. The mobile phase consisted of water and acetonitrile acidified with 1% formic acid using a gradient method with total run time of 10 min...
November 6, 2018: Bioanalysis
Yashpal S Chhonker, Veenu Bala, Daryl J Murry
The quantification of eicosanoids and their metabolites in biological samples remain an analytical challenge, even though a number of methodologies/techniques have been developed. The major difficulties encountered are related to the oxidation of eicosanoids and their low quantities in biological matrices. Among the known methodologies, liquid chromatography-mass spectrometry (LC-MS/MS) is the standard method for eicosanoid quantification in biological samples. Recently advances have improved the ability to identify and simultaneous quantitate eicosanoids in biological matrices...
November 6, 2018: Bioanalysis
Joseph M Taylor, Andrew T Hughes, Anna M Milan, James Rudge, Andrew S Davison, Lakshminarayan R Ranganath
AIM: Alkaptonuria is a disorder of tyrosine metabolism where elevated circulating homogentisic acid causes progressive dysfunction of collagenous tissues. Logistical, financial and patient experience concerns with collection and transport of specimens to central laboratories makes evaluation of microsampling attractive. METHODOLOGY: Volumetric absorptive microsampling devices were evaluated for accuracy, precision and drying time. Elution methods were evaluated for several urinary metabolites of interest and stability assessed under multiple conditions...
November 6, 2018: Bioanalysis
Yi Wang, Naomi Fujioka, Chengguo Xing
Aim, materials & methods: Urinary cortisol profile has the potential as a diagnostic biomarker. We therefore developed a stable-isotope dilution ultraperformance chromatography multistage MS-based method to quantify cortisol and 16 metabolites in human urines. Results & conclusion: The LOD for cortisol and its metabolites ranges from 0.02 to 5.81 pg/μl urine. The inter- and intraday variations were 3.7-12.9% and 3.5-15.6%, respectively. Among the metabolites analyzed, significant person-to-person heterogeneity was observed, demonstrating the need for comprehensive metabolite profiling in diagnosis...
November 6, 2018: Bioanalysis
Faye Vazvaei
No abstract text is available yet for this article.
November 6, 2018: Bioanalysis
Ana Stajić, Jelena Maksić, Đoko Maksić, Guro Forsdahl, Mirjana Medenica, Biljana Jančić-Stojanović
AIM: An ultra pressure liquid chromatography (UPLC)/MS/MS method for vancomycin and teicoplanin determination in human plasma was developed in accordance with analytical quality by design (AQbD) concept and fully validated. MATERIALS & METHODS: Chromatographic separation was performed on ACQUITY UPLC C18 charge surface hybrid (CSH) column (2.1 mm × 50 mm, 1.7 μm particle size) in gradient mode and the mobile phase consisted of 0.1% formic acid in water and pure acetonitrile...
November 6, 2018: Bioanalysis
Morten Anders Kall, Marco Michi, Barry van der Strate, Achim Freisleben, Daniela Stoellner, Philip Timmerman
With 10 years of experiences on incurred sample reanalysis (ISR) as an integrated part of regulated bioanalysis, the European Bioanalysis Forum has reflected on the implementation and the use of ISR. Three surveys were conducted in 2016 and 2017 as a revisit of the ISR experiences within European pharmaceutical industry and Contract Research Organizations: has ISR become a tool for postvalidation and process check of a bioanalytical method performance and has ISR become a routine in our laboratories? Do we agree on the interpretation of guidelines/guidance and are we aligned in our approach - among others?...
November 6, 2018: Bioanalysis
Iti Mehta, Philippe Zimmern, Larry Reitzer
AIM: Urinary tract infections (UTIs) are increasingly antibiotic resistant, and alternate or adjunct therapies are urgently needed. Several studies suggest that D-mannose ingestion and a hypothesized increase in urinary D-mannose reduce UTI frequency. Our goal was to develop a reliable assay for urinary D-mannose, which is needed to assess the effects of supplemental D-mannose on urinary D-mannose and UTIs. RESULTS: We developed an enzymatic assay for D-mannose in urine...
November 6, 2018: Bioanalysis
Brittany Maria Timmons, Laura Hay, Jim Gorman, Bruce Stouffer
No abstract text is available yet for this article.
November 6, 2018: Bioanalysis
Florence R Wang, Jing Fei, Xiao-Lan Yu, Xi-Cheng Zhao, Qian Wang, Kalmorat Metavarayuth
AIM: To investigate the efficiency of two new fast-acting enzymes, recombinant arylsulfatase (IMCS-PSF) and mutant β-glucuronidase from Escherichia coli (IMCSzyme), in hydrolyzing specific terbutaline metabolites. MATERIALS & METHODS: Two purified novel enzymes are used to precisely determine the amount of each metabolite in urine at different time points after oral administration. After systematically evaluating the hydrolysis efficiency of the novel enzymes compared with commercially available enzymes, these recently developed enzymes were applied to establish the separate urine concentration profiles of terbutaline and each metabolite...
October 29, 2018: Bioanalysis
Scott Summerfield, Roger Hayes, Meina Liang, Afshin Safavi, Dominic Warrino, Lina Luo, Ian Moore
No abstract text is available yet for this article.
October 23, 2018: Bioanalysis
Yashpal S Chhonker, Liping Ma, Constant Edi, Daryl J Murry
AIM: A sensitive and selective LC-MS/MS method was validated for quantitation of ivermectin (IVM) in plasma. METHOD: The IVM was extracted from plasma using solid-phase extraction with C-18 cartridges. Separation of analytes was achieved on an ACE C18 column with isocratic elution using 0.1% acetic acid and methanol: acetonitrile (1:1, v/v) as mobile phase. The IVM was quantitated using electrospray ionization operating in negative multiple reaction monitoring mode...
October 16, 2018: Bioanalysis
Scott G Summerfield, Matthew Barfield, Stephen A White
Outcomes of incurred sample reanalysis (ISR) studies have been reviewed from a decade of internally supported bioanalysis. From over 1000 bioanalytical pharmacokinetic end points, 26 bioanalytical studies have failed against predefined ISR acceptance criteria, ultimately resulting in the rejection of three partial and two full datasets (instability or preanalytic contamination). The remaining investigations highlighted methodological root causes including unexpected within-study assay variability, inappropriate assay range and sample homogeneity...
October 16, 2018: Bioanalysis
John F Kellie, Molly Z Karlinsey
Biotherapeutic drugs have emerged in quantity in pharmaceutical pipelines, and increasingly diverse biomolecules are progressed through preclinical and clinical development. As purification, separation, mass spectrometer detection and data processing capabilities improve, there is opportunity to monitor drug concentration by traditional ligand-binding assay or MS measurement and to monitor metabolism, catabolism or other biomolecular mass variants present in circulation. This review highlights approaches and examples of monitoring biotransformation of biotherapeutics by MS as these techniques are poised to add value to drug development in years to come...
October 16, 2018: Bioanalysis
Terry Podoll, Lisa Geisler, Michael Van Parys, Glenn Hanson, Michael J Reid
AIM: A sensitive method to quantify emixustat and its rapidly formed three major deaminated metabolites in human plasma was necessary to determine exposure in clinical trials. METHODS: An LC-MS/MS method was validated for accuracy and precision, linearity, carry over, selectivity, recovery, matrix effects, hematocrit effects and stability. RESULTS: A quantitative procedure for the determination of emixustat, ACU-5116, ACU-5124 and ACU-5149 in human plasma over the concentration range of 0...
October 16, 2018: Bioanalysis
Luna Liu, Keyang Xu, Jenny Li, Mauricio Maia, Mary Mathieu, Rebecca Elliott, Jihong Yang, Ihsan Nijem, Surinder Kaur
BACKGROUND: Hybrid ligand-binding (LB) LC-MS/MS protein quantitative assays involve a LB step for analyte enrichment that has less stringent requirements than the conventional LB assays. RESULTS: Herceptin™(trastuzumab) binding to HER2 extracellular domain was evaluated using on-bead and off-bead capture formats. The two formats yielded significantly different trastuzumab concentrations in human and monkey serum pharmacokinetic samples. Biotransformations, including deamidation of asparagine and isomerization of aspartic acid near the complementarity-determining regions of trastuzumab, had a profound impact on the LB step for analyte enrichment and trastuzumab quantification...
October 16, 2018: Bioanalysis
Cecilia Arfvidsson, Amanda Wilson, Maria Heijer, Christopher Bailey, Paul Severin, Fiona Milligan, Maryann Ngeny, Brian Dayton, Yan Li, Stephanie Cape
In this paper, experiences and learnings are shared from the 10-year application of incurred sample reanalysis (ISR) in support of the AstraZeneca small molecule portfolio. The conclusions from including ISR in every clinical bioanalysis study for a period of 5 years, generating ISR data from 550 studies, are shared. Our preclinical ISR approach is described and data generated using capillary microsampling demonstrate confidence in its routine application. The data demonstrate that ISR failures are very rare and the assessment can and should therefore be limited...
October 16, 2018: Bioanalysis
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