Magnetoswitchable charge transport and bioelectrocatalysis using maghemite-Au core-shell nanoparticle/polyaniline composites

The synthesis and novel functions of a new composite material consisting of maghemite-Au core-shell nanoparticles (NP) embedded in polyaniline is presented. The hybrid system revealed magnetoswitchable charge transport properties in the absence and presence of an external magnetic field. The attraction and the shrinking of the polymer by an external magnet enhance the charge transport through the polymer by shortening the inter-particle electron transfer distances. The magnetoswitchable electron transport properties through the polymer were then employed for the cyclic magnetoswitchable bioelectrolyzed oxidation of glucose. The magnetoswitchable bioelectrocatalytic activation of glucose is reversible, and upon removal of the external magnet the NPs/PAn film relaxes to the configuration that is less effective for mediating the bioelectrocatalytic oxidation of glucose.