The SEAS Nanotechnologies Program

Professor Michael Keidar of the Department of Mechanical and Aerospace Engineering directs GW's Micropropulsion and Nanotechnology Laboratory (MpNL), where he and his team study plasmas and their applications to healthcare, energy, defense, communications, and other sectors.

The MpNL currently has three main projects that work toward very different applications. One project uses plasmas to create new micro-propulsion devices called micro-vacuum arc thrusters, which provide small forces that can be used to correct or sustain satellites in their orbits. According to Professor Keidar, the primary benefit of this kind of device is that it can operate for very long periods of time without any degradation of performance-the main problem with micro-propulsion these days-and this means that, unlike other similar devices, it could be used to go into a deep space mission.

A second project uses plasmas to grow new carbon nanotubes, which when used with hydrogen in a gaseous phase, could have great applications in hydrogen storage, and this could help create clean energy sources for our automotive industry. Professor Keidar explains, "They can also be used as a bridge or connector between two electrodes that will be able to create a nano-device, and for this you need to be able to control the length of the nanotube. We're trying to establish what the limit is of the length of nanotubes, and we've already had some success in growing relatively long tubes and increasing their growth by a factor of 10. In this project, I'm collaborating with Professor Mona Zaghloul from the Department of Electrical and Computer Engineering."

The third project has provided the biggest breakthrough thus far. Working in collaboration with Dr. Mary Ann Stepp, a cell biologist with GW's Department of Anatomy, Professor Keidar and his team have had a great deal of success using plasmas for biomedical applications. With support from GW's Institute for Biomedical Engineering, they generated a device called a cold atmospheric plasma jet, which they used to look at the interaction between it and skin-type tissue cells. They found that they can kill an individual cell without damaging the neighboring cells, which is helpful in treating skin cancer; they can manipulate a large number of cells and change their properties without damaging them; and they can change cell migration velocity, which could help in slowing down wound healing (to lessen the formation of scar tissue in younger patients) or possibly speed it up in older patients.