Simulation of the impact of reversible adsorption on the response time of interdigitated electrode arrays

Authors

  • Kay J. Krause,

    1. Institute of Bioelectronics (PGI-8/ICS-8) and JARA – Fundamentals of Future Information Technology, Forschungszentrum Jülich, Jülich, Germany
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  • Enno Kätelhön,

    1. Institute of Bioelectronics (PGI-8/ICS-8) and JARA – Fundamentals of Future Information Technology, Forschungszentrum Jülich, Jülich, Germany
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    • Current address: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, United Kingdom.
  • Andreas Offenhäusser,

    1. Institute of Bioelectronics (PGI-8/ICS-8) and JARA – Fundamentals of Future Information Technology, Forschungszentrum Jülich, Jülich, Germany
    2. IV. Institute of Physics, RWTH Aachen University, Aachen, Germany
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  • Bernhard Wolfrum

    Corresponding author
    1. Institute of Bioelectronics (PGI-8/ICS-8) and JARA – Fundamentals of Future Information Technology, Forschungszentrum Jülich, Jülich, Germany
    2. IV. Institute of Physics, RWTH Aachen University, Aachen, Germany
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Abstract

We simulate the amperometric response time of an interdigitated electrode array with respect to reversible adsorption of redox active molecules at the electrode surface. When neighboring electrodes are biased to potentials below and above the redox potential of the species under investigation, molecules can participate in repetitive reactions leading to an amplification of the Faradaic current. During collisions between molecules and electrodes, the molecules may undergo reversible adsorption. We simulate the behavior of this redox cycling process by using a discrete random walk model, which mimics the diffusive pathway of the molecules. Adsorption probabilities are implemented via the boundary conditions at the electrodes. Using this simulation, we investigate the effect of reversible adsorption on the response time of the interdigitated electrode array. pssa201330361-gra-0001

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