Zhang Wen, Fan Guozheng, Yi Huan, Jia Gan, Li Zhaosheng, Yuan Chunwei, Bai Yunfei, Fu Degang
State Key Laboratory of Bioelectronics, Demonstration Center for Experimental Biomedical Engineering Education (Southeast University), College of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, P. R. China.
College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, P. R. China.
Small. 2018 May;14(19):e1703713. doi: 10.1002/smll.201703713. Epub 2018 Apr 14.
Hydrogen peroxide (H O ) is a major messenger molecule in cellular signal transduction. Direct detection of H O in complex environments provides the capability to illuminate its various biological functions. With this in mind, a novel electrochemical approach is here proposed by integrating a series of CoO nanostructures on CuO backbone at electrode interfaces. High-resolution transmission electron microscopy (HRTEM), X-ray diffraction, and X-ray photoelectron spectroscopy demonstrate successful formation of core-shell CuO-CoO hetero-nanostructures. Theoretical calculations further confirm energy-favorable adsorption of H O on surface sites of CuO-CoO heterostructures. Contributing to the efficient electron transfer path and enhanced capture of H O in the unique leaf-like CuO-CoO hierarchical 3D interface, an optimal biosensor-based CuO-CoO-2.5 h electrode exhibits an ultrahigh sensitivity (6349 µA m m cm ), excellent selectivity, and a wide detection range for H O , and is capable of monitoring endogenous H O derived from human lung carcinoma cells A549. The synergistic effects for enhanced H O adsorption in integrated CuO-CoO nanostructures and performance of the sensor suggest a potential for exploring pathological and physiological roles of reactive oxygen species like H O in biological systems.
过氧化氢（H₂O₂）是细胞信号转导中的一种主要信使分子。在复杂环境中直接检测H₂O₂能够阐明其各种生物学功能。考虑到这一点，本文提出了一种新颖的电化学方法，即在电极界面的CuO骨架上集成一系列CoO纳米结构。高分辨率透射电子显微镜（HRTEM）、X射线衍射和X射线光电子能谱证明成功形成了核壳结构的CuO-CoO异质纳米结构。理论计算进一步证实H₂O₂在CuO-CoO异质结构表面位点上的能量有利吸附。在独特的叶状CuO-CoO分级三维界面中，有助于高效电子转移路径和增强对H₂O₂的捕获，基于生物传感器的最佳CuO-CoO-2.5 h电极对H₂O₂表现出超高灵敏度（6349 μA mM⁻¹ cm⁻²）、优异的选择性和宽检测范围，并且能够监测源自人肺癌细胞A549的内源性H₂O₂。集成的CuO-CoO纳米结构中增强H₂O₂吸附的协同效应以及传感器的性能表明，探索像H₂O₂这样的活性氧在生物系统中的病理和生理作用具有潜力。
