Earlier work by this research group developed the ability to detect cholesterol at the human oral mucosa using a microelectrode double potential pulse method. Hydrogen peroxide produced by the oxidase enzyme accumulates at the electrode-tissue interface and is oxidized serially by sequential potential step perturbations. A second step measures the background prior to significant generation of hydrogen peroxide providing semi-real-time signal correction. The corrected signal contains unremoved background that arises from reversible surface chemistry coupled to the potential perturbation where the short time between the first potential step for hydrogen peroxide oxidation and the second potential step for background measurement does not allow compete re-establishment of the surface condition that is reached during accumulation of hydrogen peroxide over longer time. The magnitude of the reversible charge correlates with the amount of exposed platinum surface atoms that serve as the catalyst for hydrogen peroxide oxidation. Normalization of data from different electrodes is possible using the negative charge that passes upon returning the potential to the initial potential after the first step. Data for detection of glucose at the human mucosa is presented.