紫外分光光度法测定复方苯甲酸涂剂中苯甲酸和水杨酸的含量

Determination of benzoic acid and salicylic acid in the benzoic acid mixture by ultraviolet spectrophotometry

目的 :建立复方苯甲酸制剂中苯甲酸和水杨酸含量的检测方法。方法 :采用紫外分光光度法 ,直接测定两组分的含量。结果 :可同时测出苯甲酸和水杨酸的各自含量 ,且吸收度与各自的浓度成良好线性关系。苯甲酸平均回收率为 1 0 0 .2 % ,RSD为 0 .2 0 %。水杨酸平均回收率为 1 0 0 .4 % ,RSD为 0 .3 2 %。结论 :本方法简便、快速、可靠 ,可用于复方苯甲酸制剂中苯甲酸和水杨酸的含量测定。

OBJECTIVE:To establish a method for determination of benzoic acid and salicylic acid in the benzoic acid mixture.METHODS:Ultraviolet spectrophotometry wa used to determine the benzoic acid content and the salicylic acid content,at 297±1nm and 230±1nm wavelengths.RESULTS:The content of benzoic acid and that of salicylic acid could be obtained respectively,and the relationship between the absorbance and the concentration was linear.The average recovery for benzoic acid was 100.2%,RSD=0.20%;and the average recovery for salicylic acid was 100.4%,RSD=0.32%.CONCLUSION:The method is simple,fast and reliable;it has been proved to be a good practice for determination of benzoic acid and salicylic acid in the benzoic acid mixture.