METHOD FOR DETERMINING THE CONCENTRATION OF SUGAR AND ELECTROCATALYTIC SUGAR SENSOR SUITABLE THEREFOR

摘要

A method for determining the concentration of sugar in the presence of interfering foreign substances, particularly for determining glucose in a body fluid, by means of an electrocatalytic sugar sensor which has a measuring electrode in which the measuring electrode is alternatingly set potentiostatically to a reactivation and a measuring potential and the current flowing during the measuring period is evaluated as the measurement signal. To prevent foreign substances from exerting an interfering influence and thereby permit a sensitive sugar determination which is reliable over an extended period of time, a hydrophilic diaphragm is arranged in front of the measuring electrode to impede the resupply of the interfering foreign substances to the measuring electrode so that a diffusion limit current adjusts itself during the reactivation phase in the oxidation of the foreign substances; and the current is evaluated with a time delay relative to the start of the measuring period.