Janchawee Benjamas, Keawpradub Niwat, Chittrakarn Somsmorn, Prasettho Supaporn, Wararatananurak Puchong, Sawangjareon Kitja
Department of Pharmacology, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand.
Biomed Chromatogr. 2007 Feb;21(2):176-83. doi: 10.1002/bmc.731.
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.
开发了一种用于测定血清中帽柱木碱水平的简单高效液相色谱技术。分离系统由一根加热至35摄氏度的C18柱、甲醇 - 水（80:20，v/v）流动相、0.8 mL/分钟的流速以及在225 nm处进行紫外检测组成。帽柱木碱的保留时间为10.09分钟，与人体血清中的任何干扰物和内标峰均能良好分离。校准曲线在0.1至10微克/毫升范围内呈线性（r = 0.9995）。使用乙醚从碱化血清中提取帽柱木碱的回收率很高（≥85%）。该方法的日内和日间精密度分别为4.29 - 5.88%RSD和7.06 - 8.45%RSD。准确度范围为 - 9.54至 + 0.67%DEV。检测限为0.03微克/毫升，定量下限为0.1微克/毫升。储备溶液中的帽柱木碱在4摄氏度下储存30天期间保持稳定。该方法成功应用于测定大鼠口服给药后血清中帽柱木碱水平的药代动力学特征。
