高效液相色谱梯度法测定雷公藤制剂中雷公藤甲素的含量

采用高效液相色谱梯度法分离测定雷公藤制剂中雷公藤甲素的含量，用国产YWG色谱柱分离，二极管阵列检测器检测，所得三维光谱与空白光谱进行差减，取波长218nm处色谱图积分，定量。与等度法比较，梯度法具有更高的分离度、灵敏度，测定雷公藤口服液中雷公藤甲素的质量浓度为202．0μg／L，每片雷公藤片剂含甲素11．74μg，结果显著低于等度法和标示量（P<0．05）。

Determination of Triptolide in Tripterygium Preparations by Gradient High Performance Liquid Chromatography

A gradient elution method was developed for the separation and determination of triptolide in Tripterygium wilfordii Hook preparations by high performance liquid chromatography (HPLC) using YWG column made in China. Methanol with 0.05 mol/L KH2PO4 was used as mobile phase, and the photodiode array detector was used at lambda = 218 nm. The sample of tripterygium oral preparation was extracted with ethanol and then by chloroform. The extract solution was evaporated and the residue was dissolved in 10 mL of ethanol as a sample solution. The spectrum was obtained by the subtraction of spectrum of ethanol from that of sample solution. In comparing with isocratic elution, the gradient operation used in this paper had higher resolution and sensitivity. The calibration curve was linear over the range of 1.32-21.10 mg/L (r = 0.9999). The average recovery of the method was 97.59%. The method was applied to separate and determine the triptolide in tripterygium tablets and the results indicated that the triptolide content by this method was less than that by isocratic and label-claimed one.