Molecular Imprinting of Peptide Nucleic Acid (PNA) in an Electropolymerized CG-Rich Artificial Oligomer Analogue for Determination of Genetically Relevant Oligonucleotide

We devised and fabricated a chemosensor for selective determination of genetically relevant 5’ GCGGCGGC 3’ (G-guanine, C-cytosine) oligonucleotide. Toward that, we simultaneously synthesized electrochemically and deposited on a Pt electrode a sequence-defined octakis(2,2’-bithien-5-yl) polymerized film of a DNA hybridizing probe.1 For that purpose, we used both an approach of macromolecular imprinting in a polymer and a peptide nucleic acid (PNA) template of a programmable sequence. For transducing an oligonucleotide recognition event into the analytical signal, we applied electrochemical impedance spectroscopy (EIS) and surface plasmon resonance (SPR) spectroscopy under stagnant-solution and flow-injection analysis (FIA) conditions, respectively. Using EIS, we determined the target oligonucleotide with the 200 pM limit of detection. With the EIS determined apparent impact factor, IF4.0, the chemosensor discriminated both two-nucleotide-mismatched oligonucleotides and Dulbecco Modified Eagle Medium sample interferences.