Nanomotors could combat cancer cells
Like a scene from Isaac Asimov’s sci-fi classic Fantastic Voyage, a team of engineers and chemists at Penn State University have worked to put synthetic, miniscule nanomotors into actual live human cells, propel them with ultrasonic waves and steer them magnetically. These rocket-shaped projectiles can now actually be made to move around within the cells and put to use to combat cancer.
Tom Mallouk, Evan Pugh Professor of Materials Chemistry and Physics at Penn State, elaborated: “As these nanomotors move around and bump into structures inside the cells, the live cells show internal mechanical responses that no one has seen before. This research is a vivid demonstration that it may be possible to use synthetic nanomotors to study cell biology in new ways. 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.”
Mallouk stated that in the past nanomotors have only been studied “in vitro” in lab apparatus and not in live human cells. Mallouk, chemist Ayusman Sen and physicist Vincent Cewapi created the chemically-run nanomotors ten years ago at the university. He recounted: “Our first-generation motors required toxic fuels and they would not move in biological fluid, so we couldn’t study them in human cells. That limitation was a serious problem.”
The opportunity to researching the nanomotors in living cells became a reality once he and French physicist Mauricio Hoyos established the motors could be driven with ultrasonic waves. Their first trials involved HeLa cells, a type of human cervical cancer cells generally used in research. According to Mallouk the cells ingest their nanomotors which they control through the use of the ultrasonic waves.
Mallouk stated that the ultrasonic waves don’t have much of an effect on the cells at low power but once that power is increased the miniscule motors react and move. They can basically homogenize the contents of a cell or be made to batter and even puncture a cell membrane. The researchers also discovered that these mini-motors can move independently of each other.
Mallouk explained the significance: “Autonomous motion might help nanomotors selectively destroy the cells that engulf them. If you want these motors to seek out and destroy cancer cells, for example, it’s better to have them move independently. You don’t want a whole mass of them going in one direction.”
The revelation that nanomotors can influence living cells is very important. Mallouk elaborated: “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. There are lots of applications for controlling particles on this small scale, and understanding how it works is what’s driving us.”
(Image courtesy of Azonano)