电位滴定法测定蜂胶软胶囊酸价

Determination of acid value of propolis soft capsule by potentiometric titration

中文关键词:  电位滴定  蜂胶软胶囊  酸价

英文关键词:potentiometric titration  propolis soft capsule  acid value

中文摘要:

      目的 探索蜂胶软胶囊的酸价测定方法。方法 根据蜂胶软胶囊的处方, 取蜂胶粉、白蜂蜡、植物油脂、抗氧化剂、不含蜂胶粉的混合油脂(内含白蜂蜡、植物油脂、抗氧化剂)、蜂胶软胶囊, 分别用方法1和方法2测定酸价, 以10 g/L酚酞溶液或电位滴定仪指示终点。结果 方法1, 因蜂胶粉的干扰而无法测定蜂胶软胶囊的酸价; 方法2, 以10 g/L酚酞溶液指示终点时, 在滴定过程中会出现黄色, 影响终点的判断, 采用电位滴定仪指示终点, 指示效果明显, 能得到良好的精密度。按方法2测定蜂胶软胶囊酸价, 用电位滴定仪指示终点, 测得不同批次样品重复测定结果的精密度为0.9%～2.6%, 不同批次样品不同时间测定结果的精密度为2.4%～3.7%, 测得回收率为95.6%～105.0%, 平均回收率为100.0%, RSD(%)为3.5%。结论 采用方法2, 用电位滴定仪指示终点, 能够很好消除蜂胶软胶囊内容物中蜂胶粉对蜂胶软胶囊酸价测定的干扰, 测定结果精密度良好, 准确度高, 能对蜂胶软胶囊的酸价起到质量控制的目的。

英文摘要:

      Objective To explore the determination method of acid value of propolis soft capsule. Methods Through analyzing prescription of propolis soft capsule, propolis powder, white beeswax, vegetable oils, antioxidants, mixed oil without propolis powder (including white beeswax, vegetable oils and antioxidants) were determined by method one and method two respectively, and the end-point was indicated by 10 g/L phenothalin or potentiometric titrator. Results The acid value of propolis soft capsule couldn’t be determined by method one, because it was interfered by propolis powder. When indicated the end-point by 10 g/L phenothalin, the end-point couldn’t be determined by method two because the solution appeared yellow during titration. When indicated the end-point by potentiometric titrator, good precision could be obtained. Determined by method two, and indicated the end-point by potentiometric titrator, the precision of different batches of samples was 0.9%～2.6%, and 2.4%~3.7% at different time points, with the recovery rate of 95.6%～105.0%, the average recovery rate of 100.0%, and RSD of 3.5%. Conclusions Acid value of propolis was determined by method two, and indicated the end-point by potentiometric titrator, interferd by propolis powders of propolis soft capsule content could be eliminated. The precision was good, the accuracy was high, and the quality of acid value of propolis soft capsule could be controlled.