title: High-performance liquid chromatography method for determination of carnosic acid in rat plasma and its application to pharmacokinetic study.
abstract: A sensitive and reproducible high-performance liquid chromatography method with ultraviolet detection (UV) was developed for the determination of carnosic acid (CA) in rat plasma. After simple acidification and liquid-liquid extraction of plasma samples using gemfibrozil as an internal standard, the supernatant was evaporated to dryness under a gentle stream of nitrogen. The residue was reconstituted in 200 microL before being injected into the chromatographic system. The analysis was performed on a C(18) column protected by an ODS guard column using acetonitrile-0.1% phosphoric acid (55:45, v/v) as mobile phase, and the wavelength of the UV detector was set at 210 nm. The calibration curve was linear over the range of 0.265-265.0 microg/mL with a correlation coefficient of 0.9997. The recovery for plasma samples of 0.530, 13.25, 132.5 and 265.0 microg/mL was 72.2, 87.9, 90.4 and 94.7%, respectively. The intra-day and inter-day relative standard deviations for the measurements of quality control samples were less than 3.1%. The stability of the plasma samples was also validated. This method was successfully used to study the pharmacokinetics and bioavailability of CA in rats.
authors.affiliation: School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, People's Republic of China.
authors.forename: Haixia
authors.initials: H
authors.lastname: Yan
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Xingnuo
authors.initials: X
authors.lastname: Li
authors.forename: Chun
authors.initials: C
authors.lastname: Yu
authors.forename: Ke
authors.initials: K
authors.lastname: Zhang
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.forename: Lijun
authors.initials: L
authors.lastname: Wu
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.forename: Pengfei
authors.initials: P
authors.lastname: Tu
mesh_terms: D045784:Abietanes / Q000097:blood* / Q000493:pharmacokinetics; D000818:Animals; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D015248:Gemfibrozil / Q000032:analysis; D016014:Linear Models; D008297:Male; D010936:Plant Extracts / Q000097:blood* / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D045784:Abietanes; D010936:Plant Extracts; C018381:salvin; D015248:Gemfibrozil