The Grapevine

These Micro Robots May Soon Change Cancer Treatment

Doctors may soon replace surgery and chemotherapy with a new less invasive and safer process to treat cancer and other forms of tumors. Researchers developed microrobots that can deliver drugs directly to target sites in the body. 

The team from Caltech Division of Engineering and Applied Science created the robots using a technique already proven effective to identify breast tumors and cancer cells. The current version of the microrobots focus on the tumors in the digestive tract.

"The microrobot concept is really cool because you can get micro-machinery right to where you need it," Lihong Wang, a professor of medical engineering and electrical engineering at Caltech, said in a statement. "It could be drug delivery, or a predesigned microsurgery."

To create the microrobots, the researchers used microscopic spheres of magnesium metal. They coated the material with gold and parylene to prevent the effects of digestion when delivering drugs. 

For the robots to travel to their target sites, it reacts with fluids in the digestive tract to produce small bubbles and propel forward. The technique called photoacoustic computed tomography (PACT) allowed the researchers to control the robots from outside the body using infrared laser light.

The team said their microrobots currently can handle two tasks. They can perform imaging and find tumors in the digestive tract.

"These micromotors can penetrate the mucus of the digestive tract and stay there for a long time. This improves medicine delivery," Wei Gao, assistant professor of medical engineering at Caltech, said. "But because they're made of magnesium, they're biocompatible and biodegradable."

Gao and Wang tested the microrobots in animal subjects. They said the treatment was able to reach its target areas and completed its tasks.

"We demonstrated the concept that you can reach the diseased area and activate the microrobots," Gao said. Results of the test were published in the journal Science Robotics

The researchers plan to continue their study and focus on the therapeutic effects of the microrobots. They also aim to add another capability to operate in other parts of the body aside from the digestive tract.

The infrared laser light currently used to control the robots fails to reach deeper parts of the body. The team said they would use different types of propulsion systems in future tests.  

Caltech Microrobots An artist's illustration of microrobots inside the gut. Caltech