催化动力学分光光度法测定痕量钴(Ⅱ)

Determination of Trace Cobalt(Ⅱ) by Catalytic Kinetic Spectrophotometry

研究了在NaOH介质中,痕量Co(Ⅱ)对H_2O_2氧化5'-硝基水杨基荧光酮的褪色反应具有显著的催化作用,据此建立了催化动力学分光光度法测定Co(Ⅲ)的新方法。方法的线性范围为0—6μg·L^(-1),检出限为6.7×10^(-9)g·mL^(-1),相对标准偏差为1.73%—2.15%,回收率为98.0%—99.8%。方法应用于测定维生素B_(12)中痕量钴时,结果满意。

A new method for determination of trace cobalt（Ⅱ） was developed by catalytic kinetic spectrophotometry,that was based on obvious catalytic action of cobalt（Ⅰ） on oxidation fading reaction of H_2O_2 on 5＇-nitro salicyl fluorone in sodium hydroxide solution.The linear of method was 0—6μg ？ L^（-1）,the detection limit was 6.7×10^（-9）g ？ mL^（-l）,and the RSD were in the range of 1.73%—2.15%,and the recoveries were from 98.0%to 99.8%.The method is applied to determination of trace cobalt（Ⅱ）in vitamin B12 with satisfaction results.