摘要
采用沉淀法合成了以OH-、F-、Cl-为通道离子的磷灰石纳米晶体。利用其独特的多位点吸附特性,研究了磷灰石不同通道离子替换对细胞色素C直接电化学的影响。在pH7.0的磷酸盐缓冲溶液中,细胞色素C在磷灰石修饰玻碳电极表面于0.074V(vs.Ag/AgCl)附近有一对准可逆的氧化还原峰,为细胞色素C血红素辅基Fe/Fe电对的特征峰。细胞色素C与磷灰石之间的静电作用使深藏在细胞色素C内部的电活性中心靠近电极表面,加速了细胞色素C在玻碳电极表面扩散控制的准可逆单电子转移过程。其中氟磷灰石对细胞色素C直接电化学的促进作用最显著,羟基磷灰石次之,氯磷灰石最弱。
The nano-scale apatites of OH-,F-,Cl- channel-ions substitution were prepared with precipitation method. Due to the multi-adsorbing sites of apatites, the influence of apatite channel-ions substitution on the direct electrochemical of cyctochrome C (Cyt C) was investigated. Cyclic voltammograms of Cyt C on the apatite modified glassy carbon electrodes show a pair of well-defined and nearly reversible peaks at about 0.074 V (vs. Ag/AgCl) in pH 7.0 phosphat buffer solution, being the characteristic peaks of the Cyt C heme Fe(III)/Fe(II) redox couples. The experimental results support that the electrostatic interaction between Cyt C and apatite gives a rapid one-electron diffusion-controlled electron transfer. The P sites of negative charges on apatite attached to the positive charges of the lysine residues, which made the heme sites of Cyt C take effective orientation and allowed the direct electron transfer to take place. The promotion of fluorapatite for the electron transfer of Cyt C was the most remarkable one and the chlorapatite was the weakest. This derived from the different electrostatic interaction between apatite and Cyt C.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2004年第12期1613-1616,共4页
Chinese Journal of Analytical Chemistry
