Implantable sensor tracks cancer in the body

March 16, 2011 | Source: New Scientist Health
Capsule-Sensor

Capsule monitors tumors and heart attacks (Photo: Christophoros Vassiliou and Michael Cima/MIT)

Researchers led by Michael Cima at the Massachusetts Institute of Technology have developed a tumor-tracking capsule small enough to fit inside a needle to implant in the body during a biopsy.

Magnetic nanoparticles fill the capsule’s hollow interior, each sporting a few monoclonal antibodies. These are proteins engineered to bind to molecules of interest, such as human chorionic gonadotrophin (hCG), a hormone that tumor cells overproduce in testicular and ovarian cancers.

A semi-permeable membrane allows molecules to flow into the capsule, but prevents the nanoparticles from drifting out. To read the device and evaluate whether a nearby tumor is receding or growing, doctors use an MRI scan to detect clusters of cancer-related molecules within the device.

The device has been tested with mice injected with human cancer cells, and has also been used to measure the severity of damage from heart attacks induced in mice.