Recently we showed the reduction and oxidation of six natural 2'-deoxynucleosides in the presence of the ambient oxygen using the very broad potential window of a pyrolytic graphite electrode (PGE). Using the same procedure, 2'-deoxynucleoside analogs (dNs) that are parts of an artificially expanded genetic information system (AEGIS) were analyzed. Seven of the eight tested AEGIS dNs provided specific signals (voltammetric redox peaks). These signals, described here for the first time, will be used in future work to analyze DNA built from expanded genetic alphabets, helping to further develop AEGIS technology and its applications. Comparison of the electrochemical behavior of unnatural dNs with the previously documented behaviors of natural dNs also provides insights into the mechanisms of their respective redox processes.

Central European Institute of Technology Masaryk University CEITEC MU Kamenice 5 625 00 Brno Czech Republic

Department of Biophysical Chemistry and Molecular Oncology Institute of Biophysics of the Czech Academy of Sciences Královopolská 135 612 65 Brno The Czech Republic

Department of NanoEngineering University of California San Diego La Jolla CA 92093 USA

Foundation for Applied Molecular Evolution 13709 Progress Blvd Alachua FL 32615 USA

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