Determination of protein-unbound rhynchiphylline brain distribution by microdialysis and ultra-performance liquid chromatography with tandem mass spectrometry

Chia Jung Lee, Thomas Y. Hsueh, Lie Chwen Lin, Tung Hu Tsai

Research output: Contribution to journalArticle

8 Citations (Scopus)


The stem with hook of Uncaria rhynchophylla (Chinese herbal name Gou-Teng) is a traditional Chinese medicine that has been ethnopharmacologically used to extinguish wind and clean interior heat. Rhynchophylline (RHY), a tetracyclic oxindole alkaloid isolated from U. rhynchophylla, displays significant antineuroinflammatory effects. However, there is no evidence to indicate that rhynchophylline can cross the blood-brain barrier and be detected in the brain. In this study, an in vivo microdialysis sampling method coupled with UPLC/MS/MS was employed for the continuous simultaneous monitoring of unbound RHY in rat blood and brain. The precursor ion→product ion transition at m/z 385.2→160.0 for rhynchophylline was monitored. A calibration curve gave good linearity (r>0.996) over the concentration range from 0.5 to 1000ng/mL. The results demonstrated that rhynchophylline could be detected in the brain and plasma from 15min to 6h after its administration (1 or 10mg/kg, i.v.). All the pharmacokinetic parameters of rhynchophylline in the brain and plasma were obtained. These results show that rhynchophylline can cross the blood-brain barrier and they provide useful clinical information.

Original languageEnglish
Pages (from-to)901-906
Number of pages6
JournalBiomedical Chromatography
Issue number6
Publication statusPublished - 2014
Externally publishedYes



  • Blood-brain barrier
  • Microdialysis
  • Pharmacokinetic parameters
  • Rhynchiphylline

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Clinical Biochemistry
  • Molecular Biology
  • Drug Discovery
  • Pharmacology
  • Medicine(all)

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