目的 建立HPLC-ELSD法测定落叶松多糖中L-阿拉伯糖和D-半乳糖。方法 色谱柱为Prevail Carbohydrate ES（250 mm×4.6 mm，5 μm），流动相为80%乙腈–0.5%乙酸铵水溶液（90∶10），体积流量1.0 mL/min，柱温室温，进样量20 μL；检测器漂移管温度为100 ℃，载气体积流量为2.5 L/min。结果 L-阿拉伯糖、D-半乳糖分别在2.004 5～20.449 5 μg（R2=0.990 5）、2.041 0～20.410 2 μg（R2=0.995 3）线性关系良好，平均加样回收率分别为99.68%（RSD为1.51%）、99.65%（RSD为1.63%）。结论 本法重现性好，稳定可靠，可作为落叶松多糖的质量控制方法。

Objective To establish a method for HPLC-ELSD determination of L-arabinose and D-galactose in polysaccharide of Larix gmelini. Methods The condition for HPLC-ELSD was Prevail Carbohydrate ES column (250 mm × 4.6 mm, 5 μm) with 80% acetonitrile-0.5% ammonium acetate solution (90∶10) as the mobile phase. The flow rate was 1.0 mL/min. The column temperature was room temperature and the detector drift tube temperature was 100 ℃.The carrier gas flow velocity was 2.5 L/min, and the injection volume was 20 μL. Results The L-arabinose and D-galactose showed good linear relationship in the range of 2.004 495—20.449 5 μg (R2 = 0.990 5) and 2.041 0—20.410 2 μg (R2 = 0.995 3), respectively; The average recoveries were 99.68% (RSD=1.51%) and 99.65% (RSD=1.63%). Conclusion The method is reproducible, reliable, and can be used for the quality control for polysaccharide of L.gmelini.