固定化肌红蛋白在水-乙醇混合溶液中的类酶活性电化学

Electrochemical study on enzyme-like activities of immobilized myoglobin in aqueous-ethanol solvent mixtures

用琼脂糖将肌红蛋白(Mb)固定到玻碳电极(GC)表面,制备了Mb-琼脂糖膜修饰电极。包埋在琼脂糖膜中的Mb在缓冲溶液和乙醇混合溶液中与电极直接传递电子,得到一对对称的Mb辅基血红素Fe(III)/Fe(II)电对的可逆氧化还原峰。其式电势随缓冲溶液pH值增加而负移,且呈线性关系,这说明Mb的电子传递过程伴随有质子的转移。在缓冲溶液和乙醇混合溶液中,固定化肌红蛋白表现出类似细胞色素P450的催化活性,能快速催化还原氯乙烷(六氯乙烷、五氯乙烷、四氯乙烷)脱氯,Mb-琼脂糖膜修饰电极具有较好的稳定性和重现性,可用于这些物质的定量检测。

Myoglobin was immobilized on the surface of a glassy carbon electrode（GCE） by agarose hydrogel.Myoglobin entrapped in the agarose film undergoes fast direct electron-transfer reaction.The formal potential（E0′） was linearly dependent on pH value of the solution,indicating that the electron transfer is proton-coupled.The immobilized Mb is able to dehalogenate chloroethanes（hexachloroethane,pentachloroethane,tetrachloroethane） which is cytochrome P450-like activity.Stability and reproducibility of the modified electrode make it possible to be used for the determination of these substances.