Self-assembled DNA monolayers

Self-assembled DNA monolayers were prepared according to a standard procedure [46, 47] by depositing 15-mers of 3 thiolated DNA on clean 200 nm thick polycrystalline gold film evaporated on glass slides. The double-stranded (ds) DNA was produced by hybridization of 3 thiolated single-stranded (ss) DNA ex situ with... 

Ferrocenylated ODNs were first immobilized in a self-assembled redox-active monolayer on Au electrodes by Letsinger and co-workers.Upon hybridization of a complementary strand, the electrochemical potential of the ferrocene changes. In addition to applications as electrochemical DNA sensors, such self-assembled DNA monolayers with electro-active groups may provide information on the mechanism of electron transfer through DNA, and indirectly also on molecular mobility within short stretches of DNA. " We have recently extended this idea by the use of immobilized metallocene-labeled PNA on Au electrodes. Because PNA is an uncharged molecule, a surface with improved properties forms, and electrochemical detection, also of single mismatches, is facilitated. 

Gorodetsky, A. A. Barton, J. K. Electrochemistry using self-assembled DNA monolayers on highly oriented pyrolytic graphite. Langmuir 2006, 22, 7917-7922. 

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