Tiny Gold Motors You Can Drive Inside Cells

They're a step toward motors doctors could one day use to deliver targeted medicine to cells in the body.

Do you think they'll meet Ms. Frizzle in there? A team of scientists has built nano-size motors, partly out of gold, that they then coaxed into cells and drove around. You can see the motors wiggling around in some cells in the video above.

In the future, engineers hope such motors will deliver medicines into cells in the body. They might also target and kill troublesome cells, such as cancer cells. For now, however, this field of study is still in its early stages. This gold-motor team is the first to implant and drive nano-motors inside living cells, according to a paper published yesterday in the journal Angewandte Chemie. They implanted their motors into cancer cells, originally harvested from a person, that scientists maintained in dishes in a lab.

In photos taken with microscopes, the motors look like little sprinkles, each less than 10 nanometers micrometers long. After scientists added the motors to a dish of cancer cells, the cells took the motors into their interiors. (Little did they know…) Then the research team, including materials scientists, engineers, physicists and chemists from China and the U.S., made the motors move by aiming pulses of ultrasound at the cells.

The scientists didn't exactly have great control over the motors' direction. The motors seemed to bump around inside the cells, the scientists report, suggesting the gold sprinkles are running into the cell's organelles, or the mini-organs cells maintain to perform functions such as making energy.

Strange to say, these aren't the only drivable, cell-sized motors in the world. This and other research teams have made micro- and nano-meter-long mini-rockets. Besides ultrasound, scientists have also experimented with controlling such motors with simple chemical reactions that would be available in bodily fluids such as blood or stomach acid. These studies are all steps toward putting these mini-rockets into the body one day.