双波长双指示剂催化光度法测定中药材中的痕量铜

文章研究在硫酸介质中,利用铜催化过氧化氢氧化甲基橙和亮绿褪色的反应体系.探讨该褪色指示反应的最佳实验条件,在此基础上建立高灵敏度测定痕量铜的动力学分析新方法.通过对该反应催化体系和非催化体系吸光度的测定,确定该体系的最大吸收峰位于波长510 nm和640 nm处.工作曲线的线性范围:0.100~2.00μg/25mL.检出限:3.64×10-9g/mL,相对标准偏差:1.2%.本方法体系稳定,灵敏度高,选择性好,用于亳州道地药材中痕量铜的测定,结果较为满意.

Dual-Wavelength and Dual-Indicator Catalytic Spectrophotometry for Determination of Trace Copper in Chinese Herb Medicines

This thesis studies on a system of oxidation fading reaction among hydrogen peroxide,methyl or-ange and brilliant green in the sulfuric acid medium. Under the best experimental conditions of the reaction discussed,a new kinetic analysis for trace copper with high sensitivity is established. A result shows that the maximum absorption peak lies at 510 nm and 640 nm respectively by means of absorbance deteriminaton in the catalytic and non-catalytic systems. The linear range of the working curve of this method is 0.100~ 2.00μg/25mL. The detection limit is 3.64 ＆#215; 10-9g/mL. The relative standard deviation is 1.2%. With highly stabili-ty,sensitivity and selectivity,the determination of trace copper can apply to genuine regional Chinese herb medicines in Bozhou,with satisfactory results.