On 12 November 2012, the extreme tech website reported a news:
Researchers at the University of Michigan have now created a flexible microthread electrode (MTE) that is only 7 micrometers in diameter, and can be bent into a full circle with a diameter of just a few hundred microns. It consists of an electrospun carbon fiber core with a thin film dielectric coating that is nonreactive inside the body. Electrospinning is increasingly being used to create finely controlled structures on microscopic scales. It can be likened to a form of 3D printing wherein the extruded material is given a charge and “shot” at a moving, oppositely charged target to build up the resulting structure layer by layer.
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