An electrochemical glucose biosensor based on the assisted transfer of H+ across a gel/liquid interface was developed. The transducer element consisted of a composite membrane prepared by assembling a micromachined polyester film with a DBS-NPOE gel layer. The biocomponent, glucose oxidase (GOx), was attached to the composite membrane by adsorption. The glucose analysis was made following the gluconic acid production by the enzymatic reaction between glucose and glucose oxidase. The change in pH was monitored by measuring the current intensity due to the transfer of H+across the interface between the organic gel and aqueous solution assisted by an ionophore present in the organic phase.