Microbubbles, drawn by magnets, deliver chemo with ultrasound

NTU scientists with microbubbles

Scientists in Singapore have developed magnetic micro-sized bubbles with cancer drugs on their surface that can be guided to gather around a tumor and then release their payload.

The team from Nanyang Technological University demonstrates the importance of multidisciplinary research groups, combining faculty from chemical and biomedical engineering as well as the schools of physical and mathematical sciences. They published their findings in the journal Asia Materials.

Filled with gas, the microbubbles can be coated with particles of both cancer drugs and iron oxide. The iron gives them their magnetic characteristic, allowing a robotic surgeon to guide the bubbles to a tumor’s location and thereby cutting back side effects associated with free chemotherapy in the bloodstream.

Once they have reached a tumor, the surgeon would then apply ultrasound to vibrate the microbubbles, shaking loose the drug, which is then close enough to enter the cancer cells more effectively.

Preliminary tests in mice demonstrated that the process can work in vivo.

“The first unique characteristic of our microbubbles is that they are magnetic,” said researcher Xu Chenjie in a news release. “After injecting them into the bloodstream, we are able to gather them around the tumor using magnets and ensure that they don’t kill the healthy cells. More importantly, our invention is the first of its kind that allows drug particles to be directed deep into a tumor in a few milliseconds. They can penetrate a depth of 50 cell layers or more--which is about 200 micrometers, twice the width of a human hair. This helps to ensure that the drugs can reach the cancer cells on the surface and also inside the core of the tumor.”

- here's the release