离子色谱法测定大承气汤中硫酸根离子含量及不确定度评价

Determination of Sulfate in Dachengqi decoction by Ion Chromatography and Measurement Uncertainty of the Method

目的建立大承气汤中硫酸根的离子色谱检测方法,并对此方法的不确定度进行评价。方法选用Ionpac AS18(2mm×250 mm)阴离子色谱柱,保护柱为Ionpac AG18(2 mm×50 mm);淋洗液为水:氢氧化钠=90∶10,流速0.25 ml.min-1;检测器为电导检测器。同时对该方法进行不确定度评价。结果该方法的相关性良好,相关系数为0.999 8,样品的加标回收率为94.72%,样品测定的RSD为1.61%,检出限为0.02 mg.kg-1,定量限为0.12 mg.kg-1。供试品溶液及离子色谱仪不确定度贡献率分别为81.52%和18.48%。结论 :该方法线性范围广,精密度及准确度好,操作简便,该方法适合大承气汤硫酸根离子含量测定。

Objective To determine sulfate in Dachengqi decoction by Ion Chromatography and set up Measurement Uncertainty of the Method. MethodsThe separation of the anion was achieved on an IonPac AS18（2 mm×250 mm） column,the protection column was Ionpac AG18（2 mm×50 mm）;with 0.25 ml·min-1 H2O∶NaOH=90∶10 used as an eluate;the conductivity detector were used in this method.And set up measurement uncertainty of the method simultaneously. ResultsThe method showed good correlation（r=0.999 8）,The recovery could reach 94.72%,the relative standard deviation（RSD） was 1.61%,and the detection limit was 0.02 mg·kg-1,the limit of quantification was 0.12 mg·kg-1.The percent of uncertainty of sample solution and Ion Chromatography is 81.52% and 18.48%. ConclusionThe method has wide linear range,high precision,accuracy and easy operation.The method is suitable for the determination of sulfate ion in Dachengqi decoction