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Updated: Jul 16, 2026

Mass Spectrometry and Luminogenic-based Approaches to Characterize Phase I Metabolic Competency of In Vitro Cell Cultures
Published on: March 28, 2017
CYP2C19-mediated (S)-mephenytoin 4'-hydroxylation assayed by high-performance liquid chromatography with radiometric
Charles L Crespi1, Thomas K H Chang, David J Waxman
1Discovery Labware, BD Biosciences, Woburn, MA, USA.
Abstract:
A reverse-phase, high-performance liquid chromatography method is described for the quantification of 4'-hydroxymephenytoin formed enzymatically from 14C-labeled (S)-mephenytoin following incubation with cDNA-expressed CYP2C19 or human liver microsomes. Analytical separation is achieved using a C18 column developed with a gradient from 10 to 100% methanol, with detection using a scintillation detector. This method is applicable to enzymatic studies for determination of CYP2C19-catalyzed (S)-mephenytoin 4'-hydroxylation activity.
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