Electrospinning Alternative Offers Controlled Fabrication of Nanofibers

Dissatisfied with the high-voltage electrical fields and low production rate associated with electrospinning processes, researchers at Harvard University (Cambridge, MA) have developed a low-voltage rotary jet-spinning technology that allows for the high-output fabrication of tiny, aligned, 3-D nanofibers. Using only a drum and a nozzle, the technique enables the production of biocompatible nanotextiles for a variety of applications, including tissue scaffolds and artificial organs.

Describing their process as a "cross between a high-speed centrifuge and a cotton candy machine," the researchers employ high-speed, rotating polymer-solution jets to extrude the nanofibers. The desired synthetic or natural material is fed into the machine and then stretched out into long fibers as a result of the high-speed spinning motion. Then, the fibers are extruded through the nozzle by hydrostatic and centrifugal pressures. Polymer-based threads that are 100 nm in diameter can be produced.

The process offers more control than electrospinning, according to the scientists. "Fiber morphology, diameter, and web porosity can be controlled by varying nozzle geometry, rotation speed, and polymer solution properties," the researchers state in an abstract for the journal Nano Letters.

Furthermore, fibers can be fabricated in an array of shapes and textures, and provide flexibility for 3-D structures. The scientists speculate that their equipment could enable the eventual production of miniature scaffolds in vivo.