Mondal Prakash Chandra, Fontanesi Claudio
Department of Chemical Physics, Weizmann Institute of Science, Rehovot, 76100, Israel.
National Institute for Nanotechnology, University of Alberta, Edmonton, T6G 2M9, AB (Canada.
Chemphyschem. 2018 Jan 5;19(1):60-66. doi: 10.1002/cphc.201701018. Epub 2017 Dec 5.
We report the experimental results of a study of the electron-transfer processes of redox-active metalloproteins bound to mixed self-assembled monolayers (SAMs) on magnetic (nickel or ultrathin gold-coated nickel) or nonmagnetic (gold) electrodes. Metalloproteins, such as hemoglobin (Hb), Cytochrome C (Cyt C), and Cyt C oxidase, are attached through electrostatic interactions to the free carboxylate or imidazole groups present in the mixed SAMs. The formation of both mixed SAMs and SAM/metalloprotein heterostructures were confirmed by using advanced surface analysis techniques, such as polarization modulation infrared reflection absorption spectroscopy and aqueous contact angle measurements. Electrochemical measurements indicated a stronger electronic coupling between Hb and Cyt C oxidase and the mixed-SAM-coated gold or gold-coated-nickel electrodes, whereas a weaker coupling was found between the protein and the pure nickel electrode. Surface coverage and the electron-transfer rate constant were estimated from the cyclic voltammetry data.
我们报告了一项关于氧化还原活性金属蛋白电子转移过程的研究实验结果，该金属蛋白与磁性（镍或超薄金涂层镍）或非磁性（金）电极上的混合自组装单分子层（SAMs）结合。金属蛋白，如血红蛋白（Hb）、细胞色素C（Cyt C）和细胞色素C氧化酶，通过静电相互作用附着在混合SAMs中存在的游离羧酸盐或咪唑基团上。使用先进的表面分析技术，如偏振调制红外反射吸收光谱法和水接触角测量法，证实了混合SAMs和SAM/金属蛋白异质结构的形成。电化学测量表明，Hb与细胞色素C氧化酶以及混合SAM涂层金或金涂层镍电极之间存在更强的电子耦合，而在蛋白质与纯镍电极之间发现较弱的耦合。根据循环伏安法数据估算了表面覆盖率和电子转移速率常数。
