CAMBRIDGE, England, May 2 (UPI) -- Researchers at the University of Cambridge have built a nano-engine small enough to fit inside a living cell. The engine, which measures a few billionths of a meter in size, is composed of gold particles bound together by a temperature-sensitive, gel-like polymer.
The polymer reacts to heat, expelling water when warmed by a laser and taking on water as it cools. This expansion and contraction, pushes the gold particles apart and pulls them back together, creating a spring or piston-like action capable of generating a force many times its energy potential.