Diffusion layer based probe-in-tube microdevice for selective analysis of electroactive species

A probe-in-tube microdevice based on the concept of diffusion layer gap electrode pair which we proposed recently was designed to selectively analyze electroactive species in the presence of interferents. In this device, a detecting probe electrode was inserted into a cylindrical tube electrode. The gap distance between both electrodes was in the range of diffusion layer thickness. The effectiveness of the device was confirmed by experiments using model system of the electrooxidation of hydrogen peroxide in solution. In practical performance of the microdevice, parameters influencing the interference-removing efficiency were investigated systematically. Under optimal conditions, selective analysis of hydrogen peroxide could be performed free from interferences.