A method for the operation and, in particular, for the reactivation of an implantable chemical sensor that measures values in bodily fluid, including the steps of wetting the sensor surface with a reactivation substance that carries out a chemical reaction on the sensor surface that removes molecules originating in the bodily fluid, or the reaction or degradation products thereof, which have collected on the sensor and dewetting the sensor surface of the reactivation substance, wherein the sensor surface is wetted and dewetted with the reactivation substance in situ.
