碘氧化法测定中药五倍子中的单宁  

Determination of Tannic Acid in Chinese Gall Nut via Oxidation with I_2

作　　者：杨景芝[1] 孙衍华[2] 王日为[2] 曲祥金[2] 白吉刚[1] 

机构地区：[1]山东农业大学生命科学学院,泰安271018 [2]山东农业大学化学与材料学院,泰安271018

出　　处：《应用化学》2005年第2期227-229,共3页Chinese Journal of Applied Chemistry

摘　　要：Oxidation reaction of tannic acid by I 2 was used in the determination of tannic acid in Chinese gall nut by ultraviolet spectrophotometry in aqueous ethanol solution, where I 2 exhibits a sensitive absorption at 289 nm. The linear regression equation of the method is A=0.018 61+0.245 3c(mg/L) with a correlation coefficient of 0.999 8. The linear response range is 0.0～2.0 mg/L, the apparent molar absorptivity is 4.14× 10 5 L/(mol·cm) and the recovery is in the range of 97.8%～104.3%. The method has the advantages of simplicity, high sensitivity and rapidity.Oxidation reaction of tannic acid by I 2 was used in the determination of tannic acid in Chinese gall nut by ultraviolet spectrophotometry in aqueous ethanol solution, where I 2 exhibits a sensitive absorption at 289 nm. The linear regression equation of the method is A=0.018 61+0.245 3c(mg/L) with a correlation coefficient of 0.999 8. The linear response range is 0.0～2.0 mg/L, the apparent molar absorptivity is 4.14× 10 5 L/(mol·cm) and the recovery is in the range of 97.8%～104.3%. The method has the advantages of simplicity, high sensitivity and rapidity.

关 键 词：单宁 五倍子 碘氧化 紫外分光光度法 

分 类 号：O657[理学—分析化学]