A wireless device designed to be injected into tumours and provide doctors with precise information as to the exact location of the tumour, and the exact dose of radiation received during treatment, is being developed by engineers at Purdue University, Indiana.

Babak Ziaie, an associate professor at the School of Electrical and Computer Engineering, and a researcher at Purdue’s Birck Nanotechnology Centre, explained that: “because organs and tumours shift inside the body during treatment, a new technology is needed to tell doctors the exact dosage of radiation received by a tumour.”

The prototype, ‘wireless implantable passive micro-dosimeter’, is enclosed in a glass capillary small enough to inject into a tumour with a syringe.

The device uses RFID technology, which does not emit damaging X-rays, and features a miniature version of dosimeters worn by workers in occupations involving radioactivity. It has no batteries and is activated with electrical coils placed next to the patient.

A key advantage of the technology is that is doesn’t require intricate circuitry, which could make the device easier and less expensive to manufacture than more complex designs. The system consists of a simple electronics devices such as capacitors and coils.

Engineers hope that the tiny dosimeter, which has a diameter of approximately 2.5mm, and is around 2cm in length, could provide up-to-date information about the cumulative dose a tumour receives over time.

Research findings are detailed in a paper appearing in the June issue of IEEE Transactions on Biomedical Engineering. The paper was written by doctoral student Chulwoo Son and Ziaie.