Highly sensitive LC-MS/MS method to estimate doxepin and its metabolite nordoxepin in human plasma for a bioequivalence study.

ABSTRACT: A selective, sensitive and rugged liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay has been developed for the simultaneous determination of doxepin (Dox) and its pharmacologically active metabolite, nordoxepin (NDox) in human plasma. The analytes and their internal standards (IS) were extracted from 500 µL of human plasma by liquid-liquid extraction using methyl tert-butyl ether. Chromatographic separation was achieved on Hypurity C₈ column (100 mm × 4.6 mm, 5 µm) using a mixture of acetonitrile-methanol (95:5, v/v) and 2.0 mM ammonium formate in 93:7 (v/v) ratio. Detection was accomplished by tandem mass spectrometry in the positive ionization and multiple reaction monitoring acquisition mode. The protonated precursor to product ion transitions studied for

SUBMITTER: Patel NP 

PROVIDER: S-EPMC6308917 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature