茶水中铜含量分析方法研究

本文研究分光光度法测定茶水中铜含量的方法。在pH=3.92的缓冲溶液中,铜离子与间氯偶氮安替比林形成蓝色络合物,其λmax为624nm,铜离子含量在0~1.6μg/mL范围内符合朗伯-比耳定律,方法的表观摩尔吸光系数为4.0×104L/(mol·cm),相关系数r为0.9980,精密度(RSD)小于4.2%,检出限为0.047μg/mL,加标回收率在93%~103%之间,符合分析要求。

Study on the analysis method of copper content in tea water

The spectrophotometry method for determination of copper was studied in this paper.In NaAc-HAc buffer solution of pH=3.92, copper can react with M-Chloro-azo-antipyrine (MCAA) to form a blue substance and can be determined by spectrophotometry at 624nm, the apparent molar absorptivity 4.0×104L/(mol·cm). Beer's law is obeyed for the mass concentration of copper in the range of 0~1.6μg/mL. The correlation coeff icient is 0.9980, the relative standard deviations(RSD) is 4.2%,the detection limit is 0.047μg/mL, and the recovery of standard addition was from 93% to 103%, according to the requirements of analysis.