PULSE VOLTAMMETRY IN SINGLE CELLS USING PLATINUM MICROELECTRODES

Multiple pulse voltammetry at platinum microelectrodes is described for intracellular measurements. In this technique, a sequence of three potential pulses is used for each current point measured. This pulse sequence provides a fixed cathodic activation potential and a fixed anodic cleaning potential before a varying detection potential, at which the current is measured. Voltammetric information is obtained by ramping the detection potential stepwise through the potential range of interest. The multiple pulse voltammetry technique has been applied to the study of the oxidation of potassium ferrocyanide, glucose, and several catechols at platinum microdisk electrodes. In addition, this technique has been applied at ultrasmall platinum ring electrodes to reduce electrode fouling during intracellular voltammetry. In these in vivo experiments, the electrode response is degraded by only 30% after 40 min of intracellular voltammetry.