高锰酸钾分光光度法测定药片中维生素B1的含量

Spectrophotometric determination of vitamin B_1 in tablets using potassium permanganate

在0．32mol／LH2SO4溶液中，维生素B1在80℃水浴恒温条件下与KMnO4发生氧化还原反应．采用分光光度法在525nm处测定KMnO4的吸光度变化值△A．△A值与维生素B1的浓度在4-40μg／mL范围内成良好的线性关系，相关系数R=0．9987，方法检出限为0．8μg／mL．将该法用于药片中维生素B1含量的测定，相对标准偏差RSD为5．2％，平均回收率为92％，结果满意．

In the medium of 0.32 mol/L sulfuric acid, vitamin B1 reacted with potassium permanganate and made the solution fade in color. The variation of the absorbance ＆A was measured at 525 nm by spectrophotometry. It was shown that the concentration of vitamin B1 and△A values had a linear relationship in the range of 4-40 μg/mL, the correlation coefficient R = 0.998 5, and the detection limit was 0.8μg/mL. This method was applied to the determination of vitamin B1 in tablets, the average recovery was 92%, and RSD was 5.2%. This method is simple, accurate, and sensitive.