The microelectrode is referred to the scale (at least one dimension) is not more than 25 μm, and the size is smaller than the diffusion layer thickness. Microelectrode has unique nature due to their small size. Increasing interests have been drawn in microelectrode fabrication and application since microelectrode possesses special features such as high current density, rapid response, immunity to ohmic drop, high signal to noise ratio. Microelectrode plays an important role in electrochemical technology for its unique properties, and there are many applications in the field of life analysis, such as the single cell detection and in vivo analysis. The preparation of microelectrode is the key to the application of microelectrode electrochemical development. According to the excellent performance of microelectrode, many technologies are involved in the preparation of microelectrode, such as electrochemical etching, electro-deposition method, self-assembly technology, electroless plating technology.Meanwhile, the preparation methods provide the possibility for rapid preparation of microelectrodes. According to different characteristics of the conventional electrodes, microelectrode research progress in recent years are reviewed, including the unique characteristics of microelectrode, classification and preparation methods of microelectrodes, applications in the field of life analysis, the challenge for the microelectrode and development direction.
Contents
1 Introduction
2 Unique characteristics of microelectrode
2.1 High current density
2.2 Immunity to ohmic drop
2.3 High signal to noise ratio
2.4 Fast mass transfer speed
2.5 Simple device
2.6 Drawbacks
3 Classification and preparation methods of microelectrodes
3.1 Carbon ultra-microelectrode
3.2 Carbon nanotube microelectrode
3.3 Carbon fiber microelectrode
3.4 Platinum microelectrode
3.5 Gold microelectrode
4 The in vivo/single cell applications of microelectrodes
4.1 In vivo detection
4.2 Single cell detection
5 Conclusion