高效液相色谱-蒸发光散射检测器检测24-表芸苔素内酯原药含量

Quantitative determination of 24-epibrassinolide by high-performance liquid chromatography with evaporative light scattering detector

建立了高效液相色谱-蒸发光散射检测器（HPLC-ELSD）检测24-表芸苔素内酯原药含量的分析方法。在优化的ELSD条件（漂移管温度50℃、增益值10、辅助气压力350kPa）下，采用Eclipse XDB C18色谱柱（250rain×4．6mm，5μm），以V（乙腈）：V（水）=55：45等度洗脱、流速为1．0mL／min、柱温30℃时，24-表芸苔素内酯原药中的有效成分和其他组分在10min内能达到基线分离。在43．8～700．7mg／L范围内，24-表芸苔素内酯峰面积的对数与质量对数间线性关系良好，回归方程的相关系数为0．9993，相对标准偏差（RSD，n=7）为0．75％，平均回收率为99．7％。该方法简单实用，可为24-表芸苔素内酯及其他芸苔素甾醇的质量控制提供一种准确可行的检测方法。

A rapid high-performance liquid chromatography with evaporative light scattering detector （HPLC-ELSD） method for determination of 24-epihrassinolide has been established. The optimized ELSD conditions were as follows： drift tube temperature is 50 ℃, gain value is 10 and the auxiliary gas pressure is 350 kPa. The determination was carried out on a Eclipse XDB C18 column （250 mm × 4. 6 mm, 5 μm） with the mobile phase consisted of acetonitrile and water （V/V =55： 45）, column temperature set at 30 ℃ and flow rate of 1. 0 mL/min. Complete separation of the main composition and impurities with similar chemical structures was achieved in 10. 0 min under optimized conditions. The developed method was fully validated. The results showed that the regression of logarithmic valueof peak area on the logarithmic value of the mass injected fitted a linear relationship well （r = 0.999 3 ） at the concentration levels ranging from 43.8 - 700.7 mg/L. The relative standard deviations （RSD, n = 7 ） was 0.75 % and the mean recovery was 99.7 %. The optimized and validated method is efficient, accurate and easy to use, which provides reliable method for determination and quality control of 24-epibrassinolide and other brassinosteroids.