Sensing at the nanoparticle trapped tip of funnel nanochannel

This paper explored the ion transportation in a funnel nanochannel with nanoparticles trapped at the tip and its applicability in nucleic acid detection. Simulation showed that H⁺ distribution in funnel nanochannel was extremely sensitive to the surface charge density of nanoparticle trapped at the tip, which contributed to the reported high sensitivity. A high sensitivity of 1fM for biotin was achieved in 100μM KCl solution. Sensing capability of 22 mer ssDNA and 22 bp dsDNA was also proved for the first time, which provided a potential application in highly sensitive microRNA detection on chip.