The development of smart polymer matrices for controlled drug delivery,([1]) improved solar energy conversion, ([2]) information storage and processing, ([3]) controlled surface properties, ([4]) machinery functions, ([5]) and other applications attracts substantial research efforts. Specifically, signal-triggered polymers that undergo phase transitions or swelling/shrinking upon an applied stimulus are of fundamental and practical utility. Electrical, ([6]) optical,([7])l thermal,([8]) pH,([9]) and chemical([10]) stimuli have been applied to polymers to stimulate phase transitions, to control their swelling degree, and to control their hydrophobicity. Different applications of signal-triggered polymer matrices for separation,([11]) drug delivery and controlled release of therapeutics, ([12]) sensors, ([13]) and information storage by photochromic([14]) or electrochromic([15]) matrices have been suggested. Also, semiconductor nanoparticle/polymer composites have been employed for chemically triggered switchable generation of photocurrents.([16]) Similarly, electroactive polymers have been used as "artificial muscles"([17]) and as active materials to induce the mobility of micro-objects.([18,19]) Here, we report on the generation of a hybrid composite consisting of maghemite-Au core-shell nanoparticles (NPs) and polyaniline on an electrode surface. We discuss the cyclic and reversible magnetic-field-induced switching of the charge transport through the polymer. We demonstrate that the attraction and shrinking of the polymer by an external magnet enhance the charge transport through the polymer, and this phenomenon is employed to develop the magneto-switchable bioelectrocatalytic oxidation of glucose.