石墨电极上琼脂糖膜固载血红蛋白的电化学性能研究

Direct electrochemistry and electrocatalysis of hemoglobin entrapped in agarose hydrogel films

用琼脂糖(agarose)将血红蛋白(Hb)固定在热裂解石墨电极表面,制备了Hb-agaose膜修饰电极.包埋在琼脂糖中的血红蛋白与电极直接传递电子.在磷酸盐缓冲溶液中得到一对可逆的血红蛋白辅基血红素Fe(Ⅲ)/Fe(Ⅱ)电对氧化还原峰,式电势为-0.299 V(vs SCE),式电势随缓冲溶液pH值增加而负移且成线性关系,直线斜率为-44 mV/pH,说明血红蛋白的电子传递过程伴随有质子的转移.并研究了Hb-agarose膜修饰电极对H2O2的电催化性质.

Hemoglobin was immobilized on edge-plane pyrolytic graphite （EPG） electrodes by agarose hydrogel. The protein entrapped in the agarose film undergoes fast direct electron-transfer reactions with the formal potential （E^o＇） of -0. 299V（vs SCE）, corresponding to Fe^Ⅲ ＋e^-→Fe^Ⅱ ,The Eo＇s are linearly dependent on solution pH with the slope value of -44 mV/pH, indicating that the electron transfer was proton-coupled. The mechanisms for catalytic reduction of hydrogen peroxide by hemoglobin entrapped in agarose hydrogel were also explored.