Shuttle electron transfer in tethered mediator biosensor

Theoretical model of mediated electron transfer processes in redox enzyme biosensor is presented. We have analyzed the charge transfer from substrate to enzyme-modified electrodes via a small mediator molecule anchored on the electrode surface by long flexible polymer. In the system considered, a mediator communicates with redox enzyme center and “shuttles” electrons to the electrode. We have shown that in this case, the output current depends on tether length and that the smaller tethers enhance the electron transfer rate.