Experimental demonstration and simulation of electrochemical non-linear responses to glucose and its interferents with an amperometric sensor

Abstract

A novel sensing system based on the multi-dimensional information contained in a dynamic non-linear response is proposed. A sinusoidal potential was applied to an amperometric-type glucose sensor and the resulting current of the sensor was analyzed by fast Fourier transformation (FFT). The amplitudes of the higher harmonics of FFT characterize the non-linear properties of the response. The amplitudes of the higher harmonics of FFT exhibit characteristic changes which depend on the concentration and the kinetics of the reactions of glucose and its interferents at the sensor surface. The essential features of the current–potential curve were reproduced by a computer simulation based on the kinetics of electrochemical reactions.