碳糊电极上无机膜固载血红蛋白的直接电化学  

Direct Electrochemistry of Hemoglobin Immobilized on Carbon Paste Electrode by Inorganic Film

作　　者：王全林[1] 杨宝军[1] 吕功煊[1] 

机构地区：[1]中国科学院兰州化学物理研究所羰基合成与选择氧化国家重点实验室,兰州730000

出　　处：《高等学校化学学报》2003年第9期1561-1566,共6页Chemical Journal of Chinese Universities

基　　金：国家"九七三"计划(批准号:G20000264)资助

摘　　要：报道了用硅溶胶-凝胶(Sol-gel)膜将血红蛋白(Hb)固载于碳糊电极上的直接电化学行为.研究结果表明,Hb-Sol-gel修饰的碳糊电极在pH=7.0的缓冲溶液中于-0.275 V(vs.Ag/AgCl)处有一对可逆的循环伏安氧化-还原峰,为Hb血红素辅基Fe(Ⅲ)/Fe(Ⅱ)电对的特征峰.HbFe(Ⅲ)/Fe(Ⅱ)电对的式量电位在pH5.0～11.0范围内与溶液pH值呈线性关系,表明Hb的电化学还原很可能是一个质子伴随着一个电子的电极过程.FTIR光谱证实,Sol-gel膜对Hb的固载没有破坏其天然结构.Hb-Sol-gel修饰的碳糊电极能够催化还原H_2O_2,可望将其用于制作第三代生物传感器.Direct electrochemical behavior of hemoglobin (Hb) immobilized on carbon paste electrodes by Sol-gel film derived from tetraethylorthosilicate was investigated for the first time. Hb-Sol-gel-modified electrodes showed a pair of well-defined and nearly reversible cyclic voltammetric peaks for HbFe(Ⅲ )/ Fe( Ⅱ ) redox couple at about -0. 275 V(vs. Ag/AgCl) in pH 7. 0 phosphate buffers. The formal potential of Hb heme Fe( Ⅲ )/Fe( Ⅱ ) couple shifted linearly between pH 5. 0-11. 0 with a slope of 51. 85 mV/ pH, suggesting that one proton was coupled to each electron transfer in the electrochemical reaction. It was demonstrated by FTIR spectra that the structure of Hb was still maintained native-like in the film. The immobilized Hb displayed the features of a peroxidase and gave an excellent electrocatalytic response to the reduction of H2O2. Consequently, this work provides a possible route of using Hb-Sol-gel-modified electrodes as the third generation biosensors.

关 键 词：碳糊电极 无机膜 固载 硅溶胶-凝胶 血红蛋白 电化学 

分 类 号：O646[理学—物理化学]