酶催化分光荧光法测定环境水中痕量铬(Ⅵ)  

Determination of trace chromium(Ⅵ) in environmental water by enzymatic catalytic spectrofluorimetry

作　　者：田丰收[1] 陈亚红[1] 方磊[1] 

机构地区：[1]周口师范学院化学系,河南周口466001

出　　处：《冶金分析》2013年第5期55-58,共4页Metallurgical Analysis

基　　金：河南省基础与前沿技术研究计划资助项目(112300410013)

摘　　要：铬(Ⅵ)对血红蛋白模拟酶催化荧光体系具有强烈的猝灭作用,据此建立了一种酶催化分光荧光法测定铬?的新方法。研究了溶液酸度、L-酪氨酸浓度、血红蛋白浓度、H2O2浓度及反应时间等因素对体系的影响。在pH 10.4的NH3.H2O-NH4Cl缓冲溶液中,当L-酪氨酸、血红蛋白和H2O2的浓度分别为1.4×10-4 mol/L、1.0×10-6 mol/L和3.5×10-5 mol/L时,测定铬(Ⅵ)的线性范围为2.0×10-6～1.0×10-4 mol/L,检出限为1.1×10-8 mol/L。1 000倍NO3-、SO42-、Na+、K+、Cl-、Br-,300倍PO43-、Al 3+、NH4+,50倍Mn2+、Mg2+、Fe2+、Cu2+,1倍Fe3+对铬(Ⅵ)的测定没有干扰。干扰较大的Fe3+,可加入过量的柠檬酸掩蔽。对浓度为4.8×10-5 mol/L的铬(Ⅵ)进行11次平行测定,其相对标准偏差为2.8%。该法已成功地应用于环境水样中铬(Ⅵ)含量的测定。According to strong quenching effect of chromium on the catalytic fluorescence system of hemoglobin analog enzyme,a novel enzymatic catalytic spectrofluorimetry for determining chromium（Ⅵ） was established.The influence of acidity,L-tyrosine concentration,hemoglobin concentration,H2O2 concentration and reaction time on the system was studied.In NH3·H2O-NH4Cl buffer solution of pH 10.4 and the presence of 1.4×10-4 mol/L L-tyrosine,1.0×10-6 mol/L hemoglobin and 3.5×10^-5 H2O2,the linear range for the determination of chromium（Ⅵ） was 2.0×10-6-1.0×10-4 mol/L and the detection limit was 1.1×10^-8 mol/L.1000 times of NO3-,SO4^2-,Na＋,K＋,Cl^-and Br-,300 times of PO43-,Al3＋,NH4＋ and 50 times of Mn2＋,Mg^2＋,Fe^2＋,Cu^2＋ and 1 time of Fe3＋ did not interfere in the determination of chromium（Ⅵ）.Fe3＋ which had more interference could be masked by adding an over dose of citric acid.The RSD was 2.8% for 11 parallel determination of 4.8×10^-5 mol/L chromium（Ⅵ）,.The method was successfully applied for determining chromium（Ⅵ） in the environment water.

关 键 词：铬(Ⅵ) 酶 催化 分光荧光法 血红蛋白 环境水样 

分 类 号：O657.39[理学—分析化学]