建立了微乳液相色谱(MELC)测定中药复方制剂清开灵注射液中黄芩苷含量的分析方法,并考察了微乳流动相的组成及pH值等影响因素。最佳条件为:采用Hypersil BDS C185μm(4.6 mm×150 mm)色谱柱,柱温30℃,以3%十六烷基三甲基溴化铵-0.8%乙酸乙酯-7%乙腈-0.01 mol/L四丁基溴化铵(磷酸调pH至3.0)为流动相,检测波长276 nm。对照品和样品均用70%甲醇处理。结果表明,黄芩苷的线性范围为25-100 mg/L,相关系数r=0.999 9。精密度实验和稳定性实验的RSD分别为1.0%(n=6)和0.50%(n=5),平均加标回收率和RSD值(n=6)分别为99%、1.9%。市售9批样品中黄芩苷的质量浓度为4.05-5.05 g/L,符合药典规定。
A method for the determination of baicalin in qingkailing injection was established by microemulsion liquid chromatography (MELC). Influential factors, including types and concentrations of the surfactant, oil phase, cosurfaetant and organic solvent additive, and pH value in the mobile phase, were discussed. The optimized conditions for the determination were as follows: analytical column: a Hypersil BDS C18 5 μm(4. 6 mm × 150 mm) ; temperature: 30 ℃ ; mobile phase: 3% cetyhrimethyl ammonium bromide - 0. 8% acetoaeetate - 7% acetonitrile - 0.01 mol/L tetrabutyl ammonium bromide ( pH = 3.0) ; flow rate : 1.5 mL/min ; detection wavelength : 276 nm. The control and real samples were dissolved with 70% methanol. The result indicated that the calibration curve was linear in the range of 25 - 100 mg/L for baiealin with correlation coefficient of 0. 999 9. The method showed good precision and stability with RSDs of 1.0% ( n = 6) and 0. 50% ( n = 5 ), respectively. The average spiked recovery was 99% with RSD(n =6) of 1.9% . The method was applied in the determination of baicalin in nine productions from legal pharmaceutical companies with satisfactory results.