毛细管气相色谱法测定穿心莲内酯乙醇残留

CGC Determination of residual organic solvents in andrographolide

目的：建立毛细管气相色谱法测定穿心莲内酯原料乙醇溶剂残留量。方法：采用气相色谱法测定，N，N-二甲基甲酰胺为溶剂，正丙醇为内标。色谱柱为DB-624石英毛细管色谱柱（30mm×0．53mm，3．0μm），载气为氮气。检测器温度：250℃；进样口温度：150℃；程序升温：初始温度70℃，保持6min，以90℃／min升温至200℃，保持5min。结果：被测物在52．3～523．4μg／ml范围内呈良好线性关系，回收率为100．2％，精密度、重复性良好。结论：方法快速，准确可靠，可用于穿心莲内酯原料中乙醇残留的检测。

OBJECTIVE To establish a method of capillary gas chromatography （CGC） for the determination of residual solvents （ethanol） in andrographolide. METHODS The method was developed by DB -624 capillary column （30 m × 0.53 mm,3.0 μm） with FID detector. The carried gas was nitrogen. The injector temperature and the detector temperature were controlled at 150 ℃ and 250 ℃, respectively. The programmed column temperature was set as follows ： maintained at 70℃ for 6 min and then raised to 200 ℃ at the rate of 90 ℃/min followed by holding for 5 min. the sample was dissolved in N, N - dimethylformamide and n - propanol was used as the internal standard. RESULTS The calibration curve showed a good linear relationship at the range of 52.3 - 523.4 μg,/ml with good precision and accuracy. CONCLUSION The method is accurate and reliable. It can be used for the determination of residual solvents （ethanol） in andrographolide.