催化分光光度法测定单硝酸异山梨酯缓释胶囊中亚硝酸根含量

Catalytic Spectrophotometric Determination of Trace Nitrite in Isosorbate Mononitrate Extended-release Capsules

基于在稀硫酸介质中亚硝酸根能催化溴酸钾氧化健那绿，建立了催化分光光度法测定痕量亚硝酸根的新方法。本方法简单、快速和灵敏，测定亚硝酸根的线性范围为２～２０ｎｇ／ｍｌ（ｒ＝０．９９９７，ｎ＝５），平均回收率为９９．４％，直接用于单硝酸异山梨酯缓释胶囊中亚硝酸根的测定，结果满意；空白辅料及大量存在的硝酸根不干扰测定。

A new catalytic spectrophotometric method for determining trace NO_2￣-, has been described. The method is based on the catalytic oxidation of Janus Green with potassium bromate in the solution of dilute H,SO,. This method is simple. rapid and sensitive. The linear range for determination is 2～20ng/ml (r= 0. 9997, n=5) for nitrite, and the average recovery is 99. 4%. The method has been used to determine NO, in Mononitrate Isosorbate Extended-release Capsules. Blank excipient and a large amount of NO, do not interfere with the determination of NO, under these experimental conditions.