Abstract: In a first embodiment, a target analyte in solution is detected by exposing the solution to an electrode that includes a conducting electroactive polymer to which a periodic alternating voltage is coupled. Upon exposure to the analyte, an electrode characteristic is varied, which variation is detected by measuring electrode current as a function of time and as a function of the periodic alternating voltage. The alternating voltage waveform has an oxidizing time period and a reduction time period, which periods and waveform duty cycle may be controlled to enhance electrode sensitivity, selectivity, and to substantially eliminate electrode fouling and data hysteresis. In a second embodiment, a receptor is bound to the electrode, to which is coupled an alternating voltage waveform that permits a mating target substance to reversibly bind to the receptor such that measurement of electrode current provides a measure of such reversible binding.