Biosensor regeneration via substrate electric potential: A physical mechanism

摘要

Literatures showed that the immune type biosensors can be regenerated by applying a voltage (△φ) across the combined macromolecules but the underlying physics was not clarified. By incorporating an electric double layer force and a van der Waals force into a weight-ensemble Brownian dynamics simulation, we found that the dissociation rate constant for biotin-streptavidin increases exponentially with △φ, and reaches 418-fold when △φ equals 1 V. Macroscopic diffusion simulations using such enhanced dissociation rate constants agree with the previous experiments, and explain quantitatively the finding that the regeneration using square-wave voltage is superior to that using saw-tooth voltage.