title: A chromatographic method for baicalin quantification in rat thalamus.
abstract: A rapid reversed-phase high-performance liquid chromatographic (rp-HPLC) assay for the determination of baicalin in rat thalamus was developed. This was carried out on a Hypersil -C(18) column using 4-nitro-benzoic acid as the internal standard with a mobile phase of methanol-water-H(3)PO(4) (45:55:0.2, v/v/v). Detection was by UV at 277 nm. The calibration curve for baicalin was linear (r=0.9992) over the concentration range of 0.05--4.0 microg/mL and the limit of detection was 10 ng/mL. The coefficients of variation of intra- and inter-day assays were 2.64, 5.19 and 3.19% and 3.46, 6.21 and 5.58% at concentrations of 0.5, 1.0 and 3.0 microg/mL, respectively. The recoveries of baicalin from rat thalamus were 85.4+/- 5.62, 90.7+/- 2.43 and 89.1+/- 4.75% at concentrations of 0.5, 1.0 and 3.0 microg/mL, respectively. The method was applied to determine the time course of baicalin in rat thalamus, following a single dosage of intravenous administration of Scutellariae radix extract at 90 mg/kg of baicalin to male Wistar rats.
authors.affiliation: Laboratory of Pharmaceutical Science, Department of Biological Science and Biotechnology, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Lujun
authors.initials: L
authors.lastname: Zhang
authors.forename: Dongming
authors.initials: D
authors.lastname: Xing
authors.forename: Yi
authors.initials: Y
authors.lastname: Ding
authors.forename: Rufeng
authors.initials: R
authors.lastname: Wang
authors.forename: Xueli
authors.initials: X
authors.lastname: Wang
authors.forename: Lijun
authors.initials: L
authors.lastname: Du
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005419:Flavonoids / Q000032:analysis* / Q000493:pharmacokinetics; D008297:Male; D010936:Plant Extracts / Q000008:administration & dosage; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D031364:Scutellaria baicalensis / Q000737:chemistry; D012680:Sensitivity and Specificity; D013788:Thalamus / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D005419:Flavonoids; D010936:Plant Extracts; C038044:baicalin