title: Simultaneous determination of baicalin, rhein and berberine in rat plasma by column-switching high-performance liquid chromatography.
abstract: A simple HPLC method using column-switching and ultraviolet detection was developed for the simultaneous determination of baicalin (BA), rhein (RH) and berberine (BE) in rat plasma. Plasma samples were injected directly onto a Capcell Pak MF C(8) column (150 mm x 4.6 mm i.d.) to remove protein and to be pre-separated by an isocratic elution using 50 mmol/L phosphate sodium (pH 6.85)-acetonitrile (10:1, v/v). After the drug-containing fractions were transferred to a Kromasil C(18) column (150 mm x 4.6 mm i.d.) by a valve switching step, the valve position was switched back and the main separation was performed by an isocratic elution using triethylamine adjusted 20 mmol/L phosphoric acid (pH 6.78)-acetonitrile (4:1, v/v). The flow rate was always 1.0 mL/min. The calibration curve showed excellent linear relationship (r>or=0.9997) over the concentration range of 0.4-7.9 microg/mL for baicalin, 0.2-7.8 microg/mL for rhein and 0.4-7.7 microg/mL for berberine in rat plasma. The intra- and inter-day assay precisions (R.S.D.) of three analytes were in the range of 0.34-4.3% and the accuracies were between 98.0% and 102.4%. Their recoveries were all greater than 95%. The method was successfully applied to the multi-constituents plasma concentration-time curve study after oral administration of a traditional Chinese medicine prescription Xiexin-Tang in rats.
authors.affiliation: Laboratory of Analytical Chemistry, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, Shanghai 200032, China.
authors.forename: Li
authors.initials: L
authors.lastname: Yi
authors.forename: Gao
authors.initials: G
authors.lastname: Jian-Ping
authors.forename: Xu
authors.initials: X
authors.lastname: Xu
authors.forename: Dai
authors.initials: D
authors.lastname: Lixin
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000880:Anthraquinones / Q000097:blood* / Q000737:chemistry; D001599:Berberine / Q000097:blood* / Q000737:chemistry; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry; D005419:Flavonoids / Q000097:blood* / Q000737:chemistry; D008297:Male; D008962:Models, Theoretical; D015394:Molecular Structure; D010936:Plant Extracts / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results
chemical_list: D000880:Anthraquinones; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D010936:Plant Extracts; D001599:Berberine; C038044:baicalin; C020491:rhein