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Background: A robust and rapid method for therapeutic drug monitoring (TDM) is urgently needed for polymyxin B, which is a last-line antibiotic for multidrug-resistant gram-negative bacteria infection. Methodology: A 3-min run of LC–MS/MS method was established to determine the main components of polymyxin B (polymyxin B1 and B2) in human plasma or urine. Solid-phase extraction […]

Background: Recent clinical trials demonstrate the benefits of the antifibrinolytic drug tranexamic acid but its pharmacokinetics remain to be investigated more in depth. Although pharmacokinetics studies are usually performed with plasma, volumetric absorptive microsampling devices allow us to analyze dried whole blood samples with several advantages. Materials & methods: High-sensitivity LC–MS/MS methods for the quantification

Historically, ligand-binding assays for pharmacokinetic samples employed duplicate rather than singlet-based analysis. Herein, the Translational and absorption, distribution, metabolism and excretion (ADME) Sciences Leadership Group of the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ) presents a study aiming to determine the value of duplicate versus singlet-based testing. Based on analysis of data

Over the past 10 years, Bioanalysis and Bioanalysis Zone have been proud to host the Bioanalysis Rising Star Award (formerly the New Investigator Award), to recognize and showcase the most promising early-career scientists in our community. The time has now come for you to select your winner for the Bioanalysis Rising Star Award 2020. We are delighted

Aim: Vitamin B12 deficiency is characterized metabolically by increased serum and urine methylmalonic acid (MMA). Urinary MMA/creatinine ratio is suggested for screening for metabolic vitamin B12 deficiency in older populations. Results: A UPLC–MS/MS method for the analysis of urinary MMA and creatinine was developed/validated. A good separation of MMA from succinic acid, its structural isomer,

Background: Pemafibrate, a novel selective peroxisome proliferator-activated receptor-α modulator, is prescribed for patients with dyslipidemia. To investigate other potential nonlipid-related effects of pemafibrate, the sensitive and rapid quantitation method for pemafibrate was required. Results: The developed LC–MS/MS assay method exhibited excellent accuracy, precision, sensitivity, stability, no matrix effect and high recovery. The LOQ (0.05 ng/ml)

Aim: A novel automated serial dried blood spot (DBS) sampler, ‘Fluispotter’, was tested for its sampling performance. Materials & methods: An LC–MS/MS method was developed for the analysis of cortisol in DBS samples serially spotted by Fluispotter. The cortisol concentrations in 148 paired DBS and plasma samples were compared across a hematocrit (HCT) range of

Aim: A major challenge for flow cytometry assays supporting clinical trials is postcollection sample stability. Here we present an approach that could mitigate the stability issue while preserving sample integrity and cellular markers, especially when enumerating rare populations such as Tregs. Materials & methods: Stability was evaluated using whole blood stored at room temperature and

Internal standard (IS) plays an important role in LC−MS bioanalysis by compensating for the variability of the analyte of interest in bioanalytical workflow. Due to the complexity of biological sample compositions and bioanalytical processes, a certain level of IS response variability across a run or a study is anticipated. However, an extensive variability may raise

Background: A LC–MS/MS method was validated for the quantification of SUVN-G3031, a novel H3 receptor inverse agonist in clinical development for the treatment of patients with narcolepsy, with and without cataplexy. Methodology: SUVN-G3031 was extracted from plasma following acetonitrile protein precipitation, separated by Ultra HPLC and quantified using positive ESI–MS/MS. Results: The method was linear