桑色素在L-半胱氨酸自组装膜修饰金电极上的电化学行为研究  

Electrochemical Behavior of Morin at a L-cysteine Self-Assembled Monolayer-Modified Gold Electrode

作　　者：黄菲[1] 曾百肇[1] 赵发琼[1] 杨玉霞[1] 

机构地区：[1]武汉大学化学与分子科学学院,武汉430072

出　　处：《分析科学学报》2004年第2期125-128,共4页Journal of Analytical Science

基　　金：中科院长春应化所电分析化学开放实验室基金

摘　　要：在0.1mol/L(pH=4.7)的HAc NaAc缓冲溶液中,用L 半胱氨酸自组装膜修饰金电极对桑色素的电化学行为进行了初步的研究,考察了修饰时间、富集时间、富集电位、扫描速度、表面活性剂、金属离子等因素对其电化学行为的影响。研究发现,桑色素在0.44V(vs.SCE)左右产生一不可逆的氧化峰。该氧化峰电流与桑色素浓度在5×10-6～2×10-4mol/L范围内呈线性关系(相关系数r=0.9989),检出限为2×10-6mol/L,这比用裸金电极测试降低一个数量级。同时发现,十六烷基三甲基溴化铵(CTAB)对氧化峰电流有一定的增敏作用。该峰且随Pb2+浓度增大而线性增高,因此可用于Pb2+的测定。A L-cysteine self-assembled monolayar-modified gold electrode is used to study the electrochemical behavior of morin in 0.1 mol/L HAc-NaAc buffer solution (pH=4.7).The effects of various factros such as modification time,deposition time,deposition potential,scan rate,surfactants,metal ions are investigated.It is found that an irreversible oxidation peak occurs at about 0.44 V (vs.SCE) and a reduction peak occurs at about 0.1 V (vs.SCE).Under the optimum conditions,there is an excellent linear relation between the oxidation peak current and concentration of morin from 5×10^(-6)mol/L to 2×10^(-4)mol/L(r=0.9989),and the detection limit is 2×10^(-6)mol/L.Also,it is found that CTAB can increase the oxidation peak current to a certain degree,and peak current increases with the increase of concentration of Pb^(2+).This is applicable for the determination of Pb^(2+).

关 键 词：桑色素 L-半胱氨酸 自组装膜 修饰金电极 电化学行为 黄酮类化合物 

分 类 号：O657.1[理学—分析化学]