重氮化-偶联显色反应分光光度法测定维生素C片的含量  

Spectrophotometric Determination of the Content of Vitamin C Tablets by Diazotisation:Coupling Chromogenic Reaction

作　　者：袁嘉怡 马卫兴 苏倩倩 Yuan Jiayi;Ma Weixing;Su Qianqian(Jiangsu Ocean University,Lianyungang 222005,China)

机构地区：[1]江苏海洋大学,江苏连云港222005

出　　处：《广东化工》2025年第1期151-153,137,共4页Guangdong Chemical Industry

基　　金：2022年江苏海洋大学研究生教育教学改革课题(YJG202210)。

摘　　要：在酸性介质下基于碘酸钾与抗坏血酸的氧化还原反应和剩余的碘酸钾与盐酸羟胺的氧化还原反应所产生的亚硝酸根离子能使对甲苯胺发生重氮化反应,其重氮化反应产物与N-1-萘乙二胺盐酸盐发生偶联反应生成紫色偶氮化合物,建立了重氮化-偶联显色反应分光光度测定抗坏血酸含量的新方法。结果表明在560 nm处工作曲线的回归方程是A=0.0566 C-0.0025,相关系数R为0.9996,其线性范围为0.40 mg·L^(-1)~12.00 mg·L^(-1),回收率在98%~102%之间。The new diazotisation reaction spectrophotometric method was set up for comtent determinatiom of vitamin C,based on the oxidation-reduction reaction of potassium iodate and ascorbic acid,and the oxidation-reduction reaction of the remaining potassium iodate and hydroxylamine hydrochloride to generate nitrite ion in acidic medium,whereas the new born nitrite ion reacted with p-toluidine to undergo diazotisation reaction,and the product formed by diazotisation reaction reacts with N-1-naphthylethylenediamine hydrochloride to generate a purple azo compound.The results showed that there was a good linear relationship between the absorbance of the system at 560 nm and the concentration of vitamin C in the range of 0.40 mg∙L^(-1)~12.00 mg∙L^(-1) with the linear regression equation A=0.0566 C(the unit of C being mg∙L^(-1))-0.0025,and the correlation coefficient R 0.9996 as well as the recovery rate at the range of 98%~102%.

关 键 词：氧化还原反应 重氮化-偶联反应 维生素C 分光光度法 片剂 

分 类 号：TQ[化学工程]