English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

This study aims to study the changes of metabolism of  Ephedra sinica Stapf  caused by processing. A sensitive and rapid high-performance liquid chromatographic tandem mass spectrometry (LC–MS-MS) method was developed for the quantitation of the major metabolite of ephedrine, 4-hydroxyephedrine, utilizing lidocaine as the internal standard in rat urine. Urine samples were precipitated with acetonitrile. Chromatographic separation was achieved on an Ultimate C18 analytical column. Detection was performed by a multiple reaction monitoring mode via an electrospray ionization source operating in the positive ionization mode. The method was linear over the concentration range of 0.05–1.0c for all components. The intra- and inter-day precision values were &lt;13.2% and the deviations ranged from −8.4% to 7.5%. The recoveries at three levels were more than 66.2%. The fully validated method was used to study the pharmacokinetic profile of 4-hydroxyephedrine in rat urine to investigate the effects caused by processing.

journal of chromatographic science

Determination of the Metabolite of Ephedrine, 4-Hydroxyephedrine, by LC–MS-MS in Rat Urine and Its Application in Excretion Profiles After Oral Administration of  Ephedra sinica Stapf  and Processing  Ephedra sinica Stapf