考察了基体辅助激光解吸电离时间飞行质谱用于人参皂甙Rg3 定量分析时内标的选择。加入棉子糖作为内标时 ,Rg3 的定量标准曲线的回归系数R2 =0 .938,平均相对误差为 2 8 6 % ;加入性质相近的芦丁后 ,Rg3 的定量标准曲线的回归系数R2 =0 993,平均相对误差为 7 5 %。分辨率的提高以及采用Rg3 和内标物的质谱峰的相对面积来代表Rg3 的浓度可以使定量的重现性明显改善 The matrix-assisted laser desorption ionization time-of-flight mass spectrometry was used to determine the internal standard of ginsenoside Rg3. With the addition of raffinose as internal standard, the regression coefficient of Rg3 quantitative standard curve was R2 = 0. 938 with the average relative error of 286%. After adding rutin with similar properties, the regression coefficient of Rg3 quantitative standard curve was R2 = 0 993, the average relative error of 75%. Increasing the resolution and using the relative area of ​​the mass peaks of Rg3 and the internal standard to represent the concentration of Rg3 results in a significant improvement in quantitative reproducibility