Tiny synthetic motors created at Pennsylvania State University are the first ever to fit inside living human cells, where they can modify the cell’s structure or even kill it. The advancement opens up new possibilities for researchers to develop disease treatments.
“This research is a vivid demonstration that it may be possible to use synthetic nanomotors to study cell biology in new ways,” Penn State materials chemistry and physics professor Tom Mallouk said in a release. “We might be able to use nanomotors to treat cancer and other diseases by mechanically manipulating cells from the inside. Nanomotors could perform intracellular surgery and deliver drugs noninvasively to living tissues.”
The actual use of nanomotors in cells is likely a decade or more away. Today’s news comes 10 years after Penn State first developed nanomotors. But before now, researchers had only tested them outside of cells.
“Our first-generation motors required toxic fuels and they would not move in biological fluid, so we couldn’t study them in human cells,” Mallouk said in the release.
The Penn State team eventually realized that sound waves could stand in for harsh chemicals as a power source, finally allowing them to test the motors in living cells. The researchers made rod-shaped nanomotors from a combination of two metals: gold and ruthenium. They placed them near HeLa cells (cervical cancer cells), which naturally swallowed the motors when they came in contact.
Once the motors were inside the cells, it was time to start the engines. The researchers found that exposing the motors to high-frequency sound waves prompted them to begin wiggling crazily around the cell. Penn State likened the effect to an egg beater. The power can be turned up or down, controlling the destructiveness of the motors.
The team further refined their control over the motors by adding magnets. Because the nanomotors are made of metal, magnets can be used to pull them in specific directions. This could allow researchers to target a very specific area of a cell or coax all of the motors to move in one direction. They can also move them with enough force that they burst through the cell wall, killing the cell.
“One dream application of ours is ‘Fantastic Voyage‘-style medicine, where nanomotors would cruise around inside the body, communicating with each other and performing various kinds of diagnoses and therapy,” Mallouk said in the release. “There are lots of applications for controlling particles on this small scale, and understanding how it works is what’s driving us.”