Magnetically Controlled Microbots for Drug Delivery and Hyperthermia Therapy in Cancer

Researchers in Daegu Gyeongbuk Institute of Science and Technology in South Korea have developed biodegradable microrobots that can be magnetically controlled to deliver drugs and provide hyperthermia treatment at the site of a tumor.

This latest research effort attempts to provide a delivery option for two different therapy pypes by creating biodegradable microrobots that can be activated when they are in the vicinity of a tumor. The microrobots consist of a biodegradable polymer loaded with magnetic nanoparticles and an encapsulated chemotherapeutic drug.

Chemotherapy is currently plagued by serious side-effects, so researchers are trying to develop more targeted nanosystems that can deliver drugs directly to the site of a tumor. Hyperthermia treatments, where heat is administered to a tumor to kill the cells within it, are gaining popularity. However, it is difficult to accurately restrict the delivered heat to the tumor site, meaning that there is potential to damage healthy tissues nearby.

Rather than affecting the entire body, the microrobots can be activated wirelessly only when they are at the site of the tumor. Using an electromagnetic actuation system to generate an alternating external magnetic field at the tumor site allowed the researchers to generate heat from the magnetic nanoparticles within the microbots, providing a local hyperthermic effect. The locomotion of the microbots can also be controlled by remotely applying a rotating magnetic field.

The heat
generated by the magnetic nanoparticles also increases the diffusion rate of the
encapsulated chemotherapeutic drug. In fact, depending on the type of magnetic
field applied, the researchers can tightly tune the drug release profile and
the achieved hyperthermic effect, to ensure optimum efficacy.

So far, the research team has tested their system in vitro, and found that the microrobots could effectively kill cultured cancer cells when they applied the appropriate magnetic fields. After the treatment is finished, the microrobots biodegrade and disappear from the body.

“We expect to improve the treatment of cancer through our
research, enhancing the efficiency of cancer treatment and reducing
side-effects,” said Hongsoo Choi, a researcher involved in the study. “By
continuously performing follow-up research with hospitals and related firms, we
will strive to develop microrobot-based precise treatment system that can be
used in actual medical sites.”

Study in Advanced
Healthcare Materials
: Magnetically
Actuated Degradable Microrobots for Actively Controlled Drug Release and
Hyperthermia Therapy

Via: Daegu
Gyeongbuk Institute of Science and Technology