So maybe paper has a place in the future, after all. Scientists at Purdue have created ferropaper, which could be used to power robots, surgical tweezers and small speakers. Ferropaper is normal paper “impregnated” with mineral oil iron oxide magnetic nanoparticles. "Because paper is very soft it won't damage cells or tissue," said Purdue professor of electrical and computer engineering and biomedical engineering, Babak Ziaie. "It is very inexpensive to make. You put a droplet on a piece of paper, and that is your actuator, or motor." "All types of paper can be used, but newspaper and soft tissue paper are especially suitable because they have good porosity," Ziaie said.

After being coated with the fluid, the paper is covered in a water-resistant biocompatible plastic film, which keeps the fluid from evaporating and strengthens the paper.

The big advantage of ferropaper is that it is inexpensive to produce and doesn’t require specialized laboratory facilities, which means it can be used in schools as a teaching tool.

Ziaie and his team have used ferropaper to construct a cantilever which can be moved with a magnetic field.

"Cantilever actuators are very common, but usually they are made from silicon, which is expensive and requires special cleanroom facilities to manufacture," Ziaie said. "So using the ferropaper could be a very inexpensive, simple alternative. This is like 100 times cheaper than the silicon devices now available."

The Purdue scientists will be revealing the results of their research at the 23rd IEEE International Conference on Micro Electro Mechanical Systems on Jan. 24-28 in Hong Kong.

By Mark Alvarez