催化光度法测定痕量铜的研究 Cu(Ⅱ)-次甲基蓝-H_2O_2体系

Catalytic Spectrophotometric Determination of Trace Copper——System of Cu(Ⅱ)-Methylene Blue-H_2O_2

在氨水介质中,痕量Cu(Ⅱ)对H_2O_2氧化次甲基蓝的反应有强烈的催化作用。由此建立的痕量CU(Ⅱ)的催化光度分析法的检测限为1.5×10^(-10)g/ml。测定范围为0～0.7μg/25ml。测得催化及非催化反应的表观活化能分别为9.15kJ/mol及14.13kJ/mol。样品分析结果良好。

A catalytic spectrophotometric method based on the oxidation of methylene blue with H_2O_2 by means of Cu(Ⅱ)as catalyst for the determination of trace Cu(Ⅱ)has been inestigated. The activation energy of catalytic and noncatalytic reactions has been measured. The detection limit is 1. 5×10^(-10)g/ml, the linear respondence is in the range of 0～0. 7μg/25ml. The effect of foreign ions has been studied and the method shows good selectivity. The proposed method has been applied to determine biological samples with satisfactory results.