铬(Ⅲ)化学发光传感器的研究

Chemiluminescence Flow Sensor for the Determination of Chromium(Ⅲ)

将Luminol-H2O2（KBr）-Cr（Ⅲ）化学发光反应体系中的发光剂Luminol用离子交换固定法固定在阴离子交换树脂上，串入流动注射系统中．H2O2是溶液里的溶解氧在流通池中电解产生的．当一定量的洗脱剂被注入阴离子交换树脂柱时，洗脱下来的Luminol及试样中的Cr（Ⅱ）在流通池中与H2O2反应，产生化学发光，实现对Cr（Ⅲ）的在线检测，从而制得Cr（Ⅲ）化学发光传感器．该传感器的线性范围是1．0×10－5－1．0×10－9mol／LCr（Ⅲ），检出限为8．5×10－11mol／LCr（Ⅲ），RSD为3.4％，单次测定可在1分钟内完成，能使用500次以上．该方法用于水样和血样中铬（Ⅲ）的测定，结果满意．

A novel chemiluminescence(CL) sensor for Chromium(Ⅲ) combined with flow-injection analysis ispresented in this paper. It is based on the catalytic effect of Chromium(Ⅲ),on the CL reaction between Luminol,immobilized electrostatically on an anion-exchange column, and hydrogen peroxide electrochemically generatedon-line via a negatively-biased electrode from dissolved oxygen in the flow cell. The sensor responds linearly toChromium(Ⅲ)concentration in the 1 .0 ×10-5 ~ 1 .0×10-9 mol/L range, and the detection limit is 8.5 ×10-11 mol/LChromium (Ⅲ).A Complete analysis, including sampling and washing, could be performed in 1 min with arelative standard deviation of <3.4%. The system is stable for over 500 determination and has been appliedsuccessfully to the determination of Chromium (Ⅲ) in tap water and blood.