This paper investigates the response of a nanoelectrode
based capacitive biosensor to the presence of single and
double strands of DNA/PNA. The expected admittance spectrum for an idealized system with cylindrical symmetry, where the biomolecule is represented by a simple dielectric and charged rod, is calculated over a broad frequency range extending from below to above the electrolyte’s dielectric relaxation cut-off frequency. DNA and PNA hybridization is also considered. The results provide indications on optimum detection conditions for admittance based DNA biosensors.
