Urinary Elimination of Ecdysterone and Its Metabolites Following a Single-Dose Administration in Humans.

Ecdysterone is a phytosteroid widely discussed for its various pharmacological, growth-promoting, and anabolic effects, mediated by the activation of estrogen receptor beta (ERbeta). Performance-enhancement in sports was demonstrated recently, and ecdysterone was consequently included in the Monitoring Program, to detect potential patterns of misuse in sport. Only few studies on the pharmacokinetics of ecdysterone in humans have been reported so far.

Automated Real-Time Tumor Pharmacokinetic Profiling in 3D Models: A Novel Approach for Personalized Medicine.

Cancer treatment often lacks individual dose adaptation, contributing to insufficient efficacy and severe side effects. Thus, personalized approaches are highly desired. Although various analytical techniques are established to determine drug levels in preclinical models, they are limited in the automated real-time acquisition of pharmacokinetic profiles.

Detection and quantitation of ecdysterone in human serum by liquid chromatography coupled to tandem mass spectrometry.

The polyhydroxylated phytosteroid ecdysterone is present in various plants (e.g. spinach).

Two dimensional chromatography mass spectrometry: Quantitation of chiral shifts in metabolism of propranolol in bioanalysis.

In this study a heart-cutting 2D-LC method was successfully developed and optimized in order to discriminate and quantitate (S)-propranolol, (R)-propranolol, and its hydroxy metabolites, namely the isomeric (S)-4'‑hydroxy propranolol, (R)-4'‑hydroxy propranolol, (S)-5'‑hydroxy propranolol, (R)-5'‑hydroxy propranolol, (S)-7'-hydroxy propranolol, and (R)-7'‑hydroxy propranolol in one chromatographic run. Thereby, experiments investigating chiral discrimination in ring hydroxylation of propranolol were made feasible. Analysis of human urine samples after administration of a single oral dose of 40 mg of propranolol clearly revealed considerable chiral shifts in propranolol and its 4'-, 5'-, and 7'-hydroxy metabolites.

Photostability testing using online reactor HPLC hyphenation and mass spectrometric compound identification illustrated by ketoprofen as model compound.

Investigations on the photochemical stability of pharmaceutical substances are mandatory in drug development and licensing as photo-induced degradation of an active pharmaceutical ingredient (API) may not only lead to decreased API concentrations but also to toxic or reactive products. Thus, the US Food and Drug Administration (FDA) and the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) issued Guidance for Industry Q1B "Photostability Testing of New Drug Substances and Products" for testing of pure but also packed drugs. However, photoproducts are also known to be generated in vivo under sunlight exposure of the skin and lead to considerable amounts of adverse drug effects.

SFC-MS/MS as an orthogonal technique for improved screening of polar analytes in anti-doping control.

HPLC is considered the method of choice for the separation of various classes of drugs. However, some analytes are still challenging as HPLC shows limited resolution capabilities for highly polar analytes as they interact insufficiently on conventional reversed-phase (RP) columns. Especially in combination with mass spectrometric detection, limitations apply for alterations of stationary phases.

Preventive doping control analysis: liquid and gas chromatography time-of-flight mass spectrometry for detection of designer steroids.

A new combined doping control screening method for the analysis of anabolic steroids in human urine using liquid chromatography/electrospray ionization orthogonal acceleration time-of-flight mass spectrometry (LCoaTOFMS) and gas chromatography/electron ionization orthogonal acceleration time-of-flight mass spectrometry (GCoaTOFMS) has been developed in order to acquire accurate full scan MS data to be used to detect designer steroids. The developed method allowed the detection of representative prohibited substances, in addition to steroids, at concentrations of 10 ng/mL for anabolic agents and metabolites, 30 ng/mL for corticosteroids, 500 ng/mL for stimulants and beta-blockers, 250 ng/mL for diuretics, and 200 ng/mL for narcotics. Sample preparation was based on liquid-liquid extraction of hydrolyzed human urine, and the final extract was analyzed as trimethylsilylated derivatives in GCoaTOFMS and underivatized in LCoaTOFMS in positive ion mode.