Fabrication and Characterization of Biomolecule-based Structure by Using SECM

1. 利用扫描电化学显微镜（SECM）在不同烷基硅烷衍生物的自组装单层（sam）玻璃衬底上进行了羟基自由基的局部电生成，并与diaphorase形成了图案。来自SECM探针（微电极）的电生成羟基自由基扩散到SAM表面并降解SAM并将其从玻璃表面移除。当SAM为疏水性时，通过将所得底物浸入到脱氢酶溶液中，在底物上形成脱氢酶图案。具有功能性末端基团的SAM也被用于通过化学连接固定脱氢酶，从而在底物上形成脱氢酶模式。SECM用于单细胞水平的细胞活动成像。基于氧还原电流的SW-480的SECM测量给出了呼吸活动的图像。活细胞的SECM测量特别适合于阐明化学和物理刺激的影响。当培养基中加入氰化物离子或硝基酚时，细胞的SECM图像变得苍白，表明这些物质降低了呼吸活性。通过对细胞活性变化的定量分析来评价细胞膜对氰化物离子的渗透性。同样，SECM也用于估算单个植物细胞的呼吸和光合活性。SECM用于估计几种氧化还原物质通过单个藻类原生质体细胞膜的渗透。当微电极靠近影响半球形扩散区形成的膜时，氧化还原电流比在体溶液中观察到的低。由于氧化还原电流的减小与膜对氧化还原物质的渗透性有关，因此对这一现象的定量分析得出了氧化还原物质通过膜的渗透系数（Pm）。Fe(CN)_6^<-4>、Fe(CN)63-、Co(phen)32_3^<+2>、FMA和对苯二酚的Pm值分别<1x10-4、<1x10-4、1x10^<-3>、5x10^<-3>和2x10^<-2> cm/sec。少

1. Scanning electrochemical microscopy (SECM) was used for localized electrogeneration of hydroxyl radical to create patterns with diaphorase on glass substrates with self-assembled mono-layers (SAMs) of different alkylsilane derivatives. The electrogenerated hydroxyl radical from the probe (microelectrode) of SECM diffused onto the SAM surfaces and degraded the SAMs and removed them from the glass surfaces. When the SAM was hydrophobic, diaphorase patterns were formed on the substrates by dipping the resulting substrate into a diaphorase solution. A SAM with functional terminal groups was also used to immobilize diaphorase via chemical linkage, giving a diaphorase pattern on the substrate.2. SECM was used for imaging of cellular activity at the single cell level. SECM measurements of SW-480 based on the reduction current of oxygen gave images of respiration activity. The SECM measurements of living cells are particularly suitable to clarify the influence of chemical and physical stimu … More lation at a single cell level. When cyanide ion or nitrophenol was added to the culture medium, the SECM image of the cell became pale, indicating that these species lowers the respiration activity. The permeation of the cellular membrane to cyanide ion was evaluated by the quantitative analysis of the change in the cellular activity. Similarly, SECM was used for estimating the respiration and photosynthetic activity of a single plant cell.3. SECM was used for estimation of permeation of several redox species through a cell membrane of a single algal protoplast. When the microelectrode is placed close to a membrane which influences the formation of the semi-spherical diffusion region, the redox current becomes lower than that observed in the bulk solution. Since the decrease in the redox current correlates with the permeability of the membrane to redox species, the quantitative analysis of the phenomena affords the permeation coefficient (Pm) for redox species to pass through the membrane. The Pm values for Fe(CN)_6^<-4>, Fe(CN)63-, Co(phen)32_3^<+2>, FMA and hydroquinone were <1x10-4, <1x10-4, 1x10^<-3>, 5x10^<-3> and 2x10^<-2> cm/sec, respectively. Less