H_2O_2-溴邻苯三酚红体系阻抑动力学光度法测定痕量EDTA  

Determination of Trace EDTA by Inhibition Kinetic-spectrophotometry in H_2O_2-Bromopyrogallol Red System

作　　者：衣秀娟 秦宏伟[2] 陈凌 陈伟 王胜 

机构地区：[1]山东省烟台经济技术开发区疾病预防控制中心,山东烟台264006 [2]山东省农业科学院中心实验室,山东济南250100 [3]德尔福派克电气系统有限公司烟台分公司,山东烟台265500

出　　处：《预防医学论坛》2009年第2期145-146,共2页Preventive Medicine Tribune

摘　　要：[目的]研究阻抑动力学光度法测定痕量EDTA的新体系。[方法]在pH=8．8的Na2BO7-HCl介质中，Fe（Ⅲ）催化H2O2氧化溴邻苯三酚红褪色的反应可被微量EDTA有效地阻抑，被过量EDTA有效的终止，据此建立了测定痕量EDTA的动力学光度法，用固定时间法在560nm波长处监测阻抑反应。[结果]方法的线性关系良好，线性范围为0～45．0μg／50ml，检出限为1．7×10^-6mg／ml，标准加入回收率为97．3％～98．0％。[结论]该方法用于罐头等食品中EDTA的测定，获得满意结果。[Objective]To study a new system of determination trace EDTA by inhibition kineticspectrophotometry.[Methods]In the Na2B4O7-HCI solution,the catalytic action of Fe（ Ⅲ ）on the oxidation of bromopyrogallol red by H2 O2 was effectively inhibited by EDTA. The reaction was effectively stopped by superfluous EDTA. The decrease in absorbance was measured at 560 nm by UV at fixed time intervals. [Results]The linear determination range is between 0 and 45.0μg/50 ml of EDTA. A detection limit of 1.7 × 10^-8 mg/ml is achieved. The recoveries are 97.3 %- 498.0 %. [Conclusion]The method can be applied to the determination of trace EDTA in canned food with satisfactory results.

关 键 词：动力学光度法 EDTA 溴邻苯三酚红 H2O2 

分 类 号：R155.5[医药卫生—营养与食品卫生学]