May 20, 2008
Nanojets impinge to form uniform channel
Electrospinning is in the news again – this time as a means of fabricating uniform nanochannels with a depth of 45 nm and a length of around 1 mm in a single step. Seon Jeong Kim and his team at Hanyang University, Korea, describe the process as being faster than lithography or focused ion beam techniques and list applications ranging from biosensing templates to nanofluidics.
To create the channel, the researchers place two metal electrodes either side of the target area and aim a polymer-loaded syringe at the substrate. A high voltage (13 kV) applied between the tip of the syringe and the sample electrodes draws the polymer solution in the direction of the substrate. When the jet of material impinges on the surface it spontaneously forms a U-shaped channel in the presence of the split electric field.
It turns out that the structure can be cut easily using an AFM tip, which opens up the possibility of tailoring the nanochannel after fabrication.
The electrospinning process takes Kim and his colleagues a step closer to their goal of developing bio-artificial muscle for implantation into the body. "We plan to use the channels to create a compact array of ferritin nanoparticles," Kim told nanotechweb.org. "Ferritin biomolecules can be used as an energy source for nano-biobatteries or as a mediator for biofuel cells, and we think that the array structure could be used to provide power to the artificial muscle."
The researchers presented their work in Nanotechnology.
About the author
James Tyrrell is editor of nanotechweb.org.