Electrochemical behavior of parallel opposed dual electrode in a microchannel

The electrochemical behavior dependent on the microchannel depth is discussed using a parallel opposed dual electrode in the microchip. The microchannel depth was controlled easily by the thickness of the photoresist. Cyclic voltammetry (CV) was carried out with conventional mode and the generation-collection mode. High collection efficiency (max: 98%) and high current amplification (max: 5.2) were achieved without miniaturizing the dual electrode by micromachining techniques, when the microchip with the microchannel depth of 30 μm was used in the generation-collection mode at low sweep rates. Quantitative analysis was applied to electrochemically reversible species with a quicker response time of around a few seconds for the same microchannel depth on chronoamperometry (CA). We observed good linearity on the calibration plot of dopamine (2 × 10^-6 - ca. 1 × 10^-3 mol dm^-3).