自组装DNA与[Co(phen)3]2+/3+相互作用的表面增强拉曼光谱法研究

对金基体上自组装ssDNA及dsDNA与钴邻菲啉配合物离子([Co(phen)3]2+/3+)相互作用进行电化学现场表面增强拉曼光谱(SERS)研究,获得相互作用位点及相互作用模式的信息.dsDNA与[Co(phen)3]2+/3+存在一定的嵌插作用,即配合物通过配体邻菲啉(phen)环以嵌插模式结合在碱基A-T及G-C富集区,同时与磷酸二酯键PO2结合,并伴随dsDNA螺旋构象由B型向A型转变;而[Co(phen)3]2+/3+则是以静电模式与ssDNA的磷酸二酯键PO2及脱氧核糖组成的骨架相互作用.

Surface Enhanced Raman Scattering(SERS) Studies on the Interaction Between Self-assembled DNA and [Co(phen)3]2+/3+

The electrochemical in situ SERS study of the interaction between [Co(phen) 3] 2 /3 and ssDNA as well as dsDNA self-assembled on the gold substrate are conducted here for the first time, and the molecular-level information of interaction is obtained. In situ SERS spectroscopic evidence shows that [Co(phen) 3] 2 /3 binds dsDNA via both the intercalative mode into the A-T and G-C-rich regions and the electrostatic mode with [Co(phen) 3] 2 /3 -PO 2 interaction. A partial reduction of B-DNA structure of dsDNA in favor of A-DNA occurs upon [Co(phen) 3] 2 /3 -dsDNA interaction. While [Co(phen) 3] 2 /3 binds ssDNA probably via electrostatic mode with [Co(phen) 3] 2 /3 -backbone interaction.