Electron transfer chemistry in synthetically modified DNA

In principal, DNA-mediated charge transfer processes can be categorized as either oxidative hole transfer or reductive electron transfer processes. The mechanisms of the latter type were elucidated using pyrene and phenothiazine as photoinducable electron donors which have been attached covalently to oligonucleotides. The results of our group support clearly the idea that the reductive type of charge transport has a high potential for molecular diagnostics, as the development of electrochemical DNA chips, and for molecular electronics, like nanodevices which are based on DNA or DNA-inspired architectures. Moreover, ethidium was incorporated as an artificial DNA base and elucidated as a charge donor for hole transfer and electron transfer. Remarkably, the combination of the fluorescence properties of ethidium together with DNA-mediated charge transfer processes represents a suitable method for the homogeneous detection of DNA base mismatches and abasic sites.