Au nanochannels technique and its application in immunoassay

Au nanotubules (channels) can be electrolessly plated within the pores of polycarbonate microporous filtra-tion membranes. When an electric field was applied on the cell consisting of the membrane and Pt electrodes, the re-sponse current decreased due to a baffle effect from big molecules when the electrolyte ion and big molecules passed through the channels modified with chemical groups. Based on this principle, a nanotubules-based sensing technique has been developed. This method can be applied to the determi-nation of human IgG with a detection limit of 0.34 ng/mL.