中药材及饮片中三种二氧化硫残留量测定方法的比较

Comparison of three methods for the determination of sulfur dioxide residues in Chinese medicinal materials and prepared pieces

目的:采用酸碱滴定法、气相色谱法、离子色谱法分别测定中药材或饮片中二氧化硫的残留量,比较分析三种检测方法的适用性。方法:采用三种检测方法对19批中药材及饮片中二氧化硫残留量进行测定,选取20种中药材及饮片进行三种方法的空白加标回收试验,并对结果进行比较分析。结果:酸碱滴定法操作简单、成本低。气相色谱法样品测定速度较快,但测定结果偏低、专属性较差。离子色谱法灵敏度高、准确度、精密度好。结论:建议气相色谱法用于粗筛二氧化硫残留量较高的样品,酸碱滴定法作为常规测定方法,离子色谱法作为仲裁方法。

Objective： The residues of sulfur dioxide in Chinese medicinal herbs and slices weredetermined by the acid-base titration, gas chromatography and ion chromatography. The suitability of these three methods was compared and analyzed. Methods： Three methods were used to determine the residues of sulfur dioxide in 19 batches of Chi- nese herbal medicines and the prepared slices, and the recovery test was performed with 20 kinds of Chinese herbal medicines and the prepared slices for three methods. The test results are compared and analyzed. Results： The acid- base titration method had the advantages of simple operation and low cost. The gas chromatography method was rapid, but the obtained test results were lower and it had the poor specificity. The ion chromatography method had the high sensitivity, accuracy and good precision. Conclusion： It is suggested that GC is used to identify the samples with high sulfur dioxide residues, acid-base titration used as the routine test method, and IC used as an arbitration method.