title: HPLC Determination of Esculin and Esculetin in Rat Plasma for Pharmacokinetic Studies.
abstract: An optimized, sensitive and validated reversed-phase high-performance liquid chromatography (RP-HPLC) method with UV detection is described for simultaneous determination of esculin and its aglycone, esculetin, in rat plasma. After addition of internal standard (chrysin), plasma samples were pretreated by solid-phase extraction and introduced into the HPLC system. Analytes were separated on a RP C18 column with a mobile phase of 0.075% acetic acid in water (solvent A) and 90% acetonitrile in solvent A (solvent B) using gradient elution at a flow rate of 1.0 mL/min. The wavelength for UV detection was set at 338 nm. Calibration curves for esculin and esculetin were constructed over a range of 10-1,000 ng/mL. The developed method was found to be specific, precise and accurate. The method was successfully applied to study the pharmacokinetics of esculin and esculetin in rats. After oral administration of 120 mg/kg, the mean Cmax values were 340.3 and 316.5 ng/mL and the AUClast values were 377.3 and 1276.5 h ng/mL for esculin and esculetin, respectively. The bioavailability of esculin was calculated to be 0.62%.
authors.affiliation: Institute of Pharmaceutical Science and Technology and College of Pharmacy, Hanyang University, Ansan, Gyeonggi-do 426-791, Republic of Korea.
authors.forename: Shaheed Ur
authors.initials: SU
authors.lastname: Rehman
authors.affiliation: Institute of Pharmaceutical Science and Technology and College of Pharmacy, Hanyang University, Ansan, Gyeonggi-do 426-791, Republic of Korea.
authors.forename: In Sook
authors.initials: IS
authors.lastname: Kim
authors.affiliation: College of Korean Medicine, Gachon University, Seongnam, Gyeonggi-do 461-701, Republic of Korea.
authors.forename: Ki Sung
authors.initials: KS
authors.lastname: Kang
authors.affiliation: Institute of Pharmaceutical Science and Technology and College of Pharmacy, Hanyang University, Ansan, Gyeonggi-do 426-791, Republic of Korea yoohh@hanyang.ac.kr.
authors.forename: Hye Hyun
authors.initials: HH
authors.lastname: Yoo
mesh_terms: D000818:Animals; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004929:Esculin / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics*; D057230:Limit of Detection; D016014:Linear Models; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results
chemical_list: D004929:Esculin