Abstract A simple, rapid and fully-validated liquid chromatographic method (RP - HPLC) with fluorescence detection was developed for the analysis of rhein (as the main metabolite of diacerein) in human plasma. The separation was performed using an ODS C18 column with a mobile phase consisted of acetonitrile:methanol:phosphate buffer pH 6.8 and the flow rate was1.0 mL/min. The flourimetric detection was performed at 2 excitation wavelengths ʎex = 440 nm & 338 nm and one emission wavelength at ʎem = 520 nm. The developed method was validated according to Food and Drug administration (FDA) guidelines for bioanalytical method validation. The pharmacokinetic parameters of the test and the reference were determined and the analysis of variance (ANOVA) between parameters of the two brands was calculated. The relative bioavailability was found to be 89%. This method was successfully applied for the routine bioequivalence analysis of diacerein in plasma.

中文翻译：

---

双醋瑞因主要代谢产物大黄酸的药代动力学及生物等效性研究

摘要 开发了一种简单、快速且经过充分验证的荧光检测液相色谱法 (RP-HPLC)，用于分析人血浆中的大黄酸（双醋瑞因的主要代谢物）。使用 ODS C18 柱进行分离，流动相由乙腈：甲醇：磷酸盐缓冲液组成，pH 6.8，流速为 1.0 mL/min。荧光检测在 2 个激发波长 ʎex = 440 nm & 338 nm 和一个发射波长 ʎem = 520 nm 下进行。开发的方法根据食品和药物管理局 (FDA) 的生物分析方法验证指南进行了验证。测定供试品和参比品的药代动力学参数，并计算两个品牌参数之间的方差分析（ANOVA）。发现相对生物利用度为89%。该方法成功应用于血浆中双醋瑞因的常规生物等效性分析。