Inorganic Nanotubes:  A Novel Platform for Nanofluidics

Templating approaches are being developed for the synthesis of inorganic nanotubes, a novel platform for nanofluidics. Single crystalline semiconductor GaN nanotubes have been synthesized using an epitaxial casting method. The partial thermal oxidation of silicon nanowires leads to the synthesis of silica nanotubes. The dimension of these nanotubes can be precisely controlled during the templating process. These inorganic nanotubes can be integrated into metal-oxide solution field effect transistors (MOSolFETs), which exhibit rapid field effect modulation of ionic conductance. These nanofluidic devices have been further demonstrated to be useful for single-molecule sensing, as single DNA molecules can be readily detected either by charge effect or by geometry effect. These inorganic nanotubes will have great implications in subfemtoliter analytical technology and large-scale nanofluidic integration.