Could tiny robots made from algae be the next big break in the fight against cancer?

CUHK researchers stress more work ahead before clinical trials can be done

PUBLISHED : Tuesday, 28 November, 2017, 5:57pm
UPDATED : Tuesday, 28 November, 2017, 10:44pm

A common algae has been used to make biodegradable microrobots that could detect diseases in the human body as well as attack cancer cells, Chinese University researchers announced on Tuesday.

The microrobots were able to release substances that attacked cancer cells during its degradation process. The devices were created from spirulina algae, which are widely used as dietary supplements.

“It is pioneering work to develop a biodegradable microrobot as this was rarely seen in the past,” said lead researcher Zhang Li, associate professor of the university’s department of mechanical and automation engineering.

Zhang, whose team worked with scientists from Britain in the research, said microrobots used inside the body had to be either excreted or completely degraded to be considered safe. Most existing microrobots are made of synthetic materials, he added, and are typically excreted or surgically removed.

The team’s findings were published in the American academic journal Science Robotics.

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To produce the latest microrobots, spirulina algae were coated with a layer of iron oxide material to create a magnetic property. The microrobots’ movements within the body could then be controlled by external magnetic force.

The fluorescent nature of the algae could be useful for tracking locations within the body and diagnosing disease, Zhang said.

The microrobots can detect whether the pH value is normal
Zhang Li, Chinese University

“The brightness level of the fluorescence is related to pH value in the surrounding environment,” he explained. “The microrobots can detect whether a pH value is normal.”

Yan Xiaohui, a researcher who was with the university when the study was carried out, said the microrobots would appear dimmer in areas that were relatively more acidic, such as locations with cancer cells. He added such observations could be achieved with the help of a fluorescence microscope.

Researchers also discovered that substances released by the microrobots during degradation attacked cancer cells without damaging healthy ones. Cells related to cervical cancer, liver cancer and skin cancer have already been tested in experiments.

But they stressed that more work had to be done before clinical trials could take place. To date, the experiments have been carried out only on mice.

Zhang said that in the future microrobots could be used for cancer treatment as well as potentially help treat diseases afflicting regions that are difficult to reach, such as the eyes and blood vessels.

Asked when clinical trials would be carried out such that the robot would be used in local hospitals, the professor said that remained uncertain as it would depend on manpower and funding.