一测多评法测定藏药小米辣中3种辣椒碱的含量

Simultaneous Determination of the Contents of Three Kinds of Capsaicinoid in Tibetan Medicine Capsicum Frutescens L. by QAMS

目的:建立藏药小米辣中3种辣椒碱类化学成分含量测定的一测多评法,探讨一测多评法在民族药质量控制中的应用。方法:采用超高压液相色谱法,使用Waters ACQUITY BEH C18(2.1 mm×100mm,1.7μm)色谱柱,流动相为乙腈-水(50︰50),流速:0.2 mL·min^(-1),柱温30℃,检测波长280 nm,进样量1μL。以辣椒素为内参物,分别建立二氢辣椒素、降二氢辣椒素相对于辣椒素的相对校正因子,分别采用外标法和一测多评法测定3种辣椒碱的含量,并通过相对标准偏差(RSD)和Pearson系数比较二者结果的相对误差。结果:降二氢辣椒素、辣椒素、二氢辣椒素进样量分别在2.21~22.1 ng、8.96~89.6 ng、3.75~37.5 ng范围内线性关系良好;降二氢辣椒素和二氢辣椒素相对于辣椒素的相对校正因子分别为0.970和1.159;且在不同实验条件下重现性良好(RSD<3.0%);一测多评法的计算结果与外标法测得结果无显著差异。10批不同产地小米辣样品中降二氢辣椒素、辣椒素和二氢辣椒素的含量范围分别为0.0281%~0.0534%、0.258%~0.389%和0.115%~0.209%。结论:建立的一测多评法可作为小米辣中3种辣椒碱类化学成分的含量测定方法,一测多评法为民族药质量控制提供了一个新的模式与方法。

Objective： To establish a quantitative analysis of multi-components by single marker（QAMS） for determination of the contents of three kinds of capsaicinoid in Tibetan medicine Capsicum frutescens L., and to discuss application of QAMS in quality control of ethnic medicines. Methods： The method of UPLC was used with a Waters ACQUITY BEH C18（2.1 mm×100 mm, 1.7 μm） column. The mobile phase was composed of acetonitrile-water（50 ∶ 50） with isocratic elution at the flow rate of 0.2 mL·min^（-1）. The detection wavelength was 280 nm, column temperature was 30 ℃, and the injection volume was 1 μL. Capsaicin was selected as an internal standard to establish the relative correction factors（RCFs） of dihydrocapsaicin and nordihydrocapsaicin with reference to capsaicin respectively. Both external standard method（ESM） and QAMS were employed for the determination of the contents of three kinds of capsaicinoid. Meanwhile, relative standard deviation（RSD） and Pearson coefficient between QAMS and ESM were analyzed to evaluate QAMS. Results： There were good linearity in the range of 2.21-22.1 ng for nordihydrocapsaicin, 8.96-89.6 ng for capsaicin, and 3.75-37.5 ng for dihydrocapsaicin, respectively. RCFs of nordihydrocapsaicin and dihydrocapsaicin with reference to capsaicin were 0.970 and 1.159, respectively, and repeatability was good in different experimental conditions（RSD 3.0%）. There were no significant differences between the quantitative results of the two methods. The contents of nordihydrocapsaicin, capsaicin and dihydrocapsaicin in 10 batches of samples of Capsicum frutescens L. were 0.0281%-0.0534%, 0.258%-0.389% and 0.115%-0.209%, respectively. Conclusion： QAMS method is feasible and credible, which can be used to determine three kinds of capsaicinoid in Capsicum frutescens L. and can be applied as a new strategy and method for the quality control of ethnic medicines.