Continuous scan cyclic voltammetry (CSCV): a new high-speed electrochemical method for monitoring neuronal dopamine release.

This report describes a new form of fast cyclic voltammetry which samples electrochemical reactions of dopamine at one every 10 ms. We have called this technique 'continuous scan cyclic voltammetry' (CSCV). The technique uses a carbon fibre microelectrode which is connected to a continuously active sine-wave source. The applied voltage is a 100 Hz precision sine wave. Faradaic signals due to cycles of continuous oxidation and reduction of dopamine at the tip of the electrode can be observed superimposed on a fixed charging current. The technique is insensitive to moderate concentrations of ascorbate as a depletion zone for ascorbate is rapidly established around the electrode. In a brain slice preparation the technique can show the time course of dopamine release on a millisecond time scale. It should prove a valuable new tool for the investigation of dopamine transmission in the brain.