Wei H Z, van de Ven T G M, Omanovic S, Zeng Y W
College of Materials Science and Engineering, Nanjing University of Technology, Nanjing, PR China.
Langmuir. 2008 Nov 4;24(21):12375-84. doi: 10.1021/la801926t. Epub 2008 Oct 8.
The interactive behavior of flavin adenine dinucleotide (FAD) with a bare glassy carbon electrode (GCE) and a Ru-modified GCE was investigated. The reduction of FAD at a GCE/ruthenium-modified GCE surface is a quasi-reversible, surface-controlled process, and our data implied that the attachment of FAD onto the surface is caused by nonspecific adsorption instead of covalent linkage, in which the adenine ring of FAD adopts a flat orientation on the GCE surface in neutral and dilute solutions in order to maximize the pi-pi stacking with the carbon surface and reorients to a perpendicular orientation as the surface gets more crowded. FAD desorption during the exchange with nicotinamide adenine dinucleotide (NAD+) is one order of magnitude slower than desorption in the absence of NAD+, which indicates a strong interaction between FAD and NAD+. General knowledge of the interactive behavior of NAD+ on a FAD-adsorbed GCE provides useful information for the design of a modified electrode surface for the generation of NADH from NAD+.
研究了黄素腺嘌呤二核苷酸（FAD）与裸玻碳电极（GCE）和钌修饰的GCE之间的相互作用行为。FAD在GCE/钌修饰的GCE表面的还原是一个准可逆的表面控制过程，我们的数据表明FAD在表面的附着是由非特异性吸附而非共价键合引起的，其中FAD的腺嘌呤环在中性和稀溶液中在GCE表面呈平面取向，以便与碳表面的π-π堆积最大化，并且随着表面变得更加拥挤而重新定向为垂直取向。与烟酰胺腺嘌呤二核苷酸（NAD+）交换期间FAD的解吸比不存在NAD+时的解吸慢一个数量级，这表明FAD与NAD+之间存在强相互作用。关于NAD+在FAD吸附的GCE上的相互作用行为的一般知识为设计用于从NAD+生成NADH的修饰电极表面提供了有用信息。
