A high-performance liquid chromatographic method for determination of mitragynine in serum and its application to a pharmacokinetic study in rats.
A simple HPLC technique for determining mitragynine levels in serum was developed. The separation system consisted of a C18 column heated to 35 degrees C, a methanol-water (80:20, v/v) mobile phase, a flow rate of 0.8 mL/min and detection in the ultraviolet at 225 nm. Mitragynine, with a retention time of 10.09 min, was well resolved from any interferences in human serum and the internal standard peak. The calibration curve was linear from 0.1 to 10 microg/mL (r = 0.9995). Extraction of mitragy-nine from alkalinized serum using diethyl ether gave a high recovery (>or=85%). The intra- and inter-day precisions of the method were 4.29-5.88%RSD and 7.06-8.45%RSD, respectively. The accuracy ranged from -9.54 to +0.67%DEV. The limit of detection was 0.03 microg/mL and the lower limit of quantification was 0.1 microg/mL. Mitragynine in the stock solution was stable during 30 days of storage at 4 degrees C. This method was successfully applied to determine the pharmacokinetic characteristics of mitragynine levels in the serum of rats after it was administered orally.
Janchawee
Benjamas
B
Department of Pharmacology, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand. benjamas.j@psu.ac.th
Keawpradub
Niwat
N
Chittrakarn
Somsmorn
S
Prasettho
Supaporn
S
Wararatananurak
Puchong
P
Sawangjareon
Kitja
K
D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D051381:Rats; D017208:Rats, Wistar; D046948:Secologanin Tryptamine Alkaloids / Q000097:blood* / Q000493:pharmacokinetics*
D046948:Secologanin Tryptamine Alkaloids; C001801:mitragynine