For the first time, scientists have succeeded in placing nano-engines into living human cells and driving these nano-engines through magnetic pairs. The nano-engines – rocket-like metal particles – are driven by ultrasonic pulses. At low doses of pulses, the nano-engines have no effect on the cells; however, when the energy of the pulses is turned up, the nano-engines are activated and come together to impact intracellular tissues and organs, thus performing specific functions. Nanomotors can be used as “egg beaters” to stir up the intracellular components, or as percussion hammers to break through cell membranes. Previously, nanomotors have been studied in vitro, but now they can be successfully studied in living human cells. This breakthrough means that in the future it may be possible to use nano-engines to mechanically manipulate the inside of cells to treat tumors and other diseases. Or molecular robots could be used to release drugs into specific parts of the body without disturbing normal tissues and organs, thus increasing the effectiveness of the drugs and reducing their side effects. Alternatively, surgery can be performed inside cells.