玄明粉主要成分为无水硫酸钠,中国药典(85年版)中硫酸钠的含量测定为重量法.该法较麻烦,误差大.为改进其含量测定方法,我们采用电导滴定法测定玄明粉中硫酸钠含量,并与重量法进行了对比实验,为修定玄明粉的标准提供参考. The main component of Xuan Ming powder is anhydrous sodium sulfate, and the content of sodium sulfate in the Chinese Pharmacopoeia (85th edition) is determined as gravimetric method. This method is more troublesome and has greater error. To improve its content determination method, we used conductivity titration to determine Xuan Ming powder. Sodium sulfate content was compared with the gravimetric method to provide reference for the revision of the Xuan Ming powder standard.