title: Determination of (-)-epigallocatechin gallate in rat blood by microdialysis coupled with liquid chromatography.
abstract: A liquid chromatographic method coupled with microdialysis was used to determine the protein-unbound (-)-epigallocatechin-3-gallate (EGCG) in rat blood. EGCG and dialysates were separated using a Merck RP-18e column maintained at ambient temperature, and a mobile phase comprised of acetonitrile-10 mM monopotassium phosphate (pH 3.82) (20:80, v/v) with a flow rate of 1.0 ml/min. The UV detector wavelength was set at 206 nm. The detection limit for EGCG was 10 ng/ml. The concentration-response relationship was linear (r2 > 0.995) over a concentration range of 0.05-10 microg/ml; intra- and inter-assay precision and accuracy of EGCG fell within predefined limits. Pharmacokinetic parameters of EGCG were assessed using compartmental models. The disposition of EGCG in the rat blood suggests that EGCG was fitted by two-compartmental model. The distribution and elimination half-lives were 6 and 72 min respectively, after the dosage of 30 mg/kg.
authors.affiliation: Taiwan National Research Institute of Chinese Medicine, 155-1, Li-Nong Street Section 2, Shih-Pai, Taipei 112, Taiwan.
authors.forename: Lie-Chwen
authors.initials: LC
authors.lastname: Lin
authors.forename: Ling-Chien
authors.initials: LC
authors.lastname: Hung
authors.forename: Tung-Hu
authors.initials: TH
authors.lastname: Tsai
mesh_terms: D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000097:blood* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017551:Microdialysis; D051381:Rats; D015203:Reproducibility of Results
chemical_list: D002392:Catechin; C045651:epigallocatechin gallate