Scientists at Lawrence Berkeley National Laboratory, Berkeley, CA, are working to develop a tiny chip that could quickly determine whether someone has been exposed to dangerous levels of ionizing radiation. The first-of-its-kind chip has an array of nanosensors that can measure the concentrations of proteins that change after radiation exposure.

Although still under development, the technology could lead to a hand-held device that would “lights up” if a person requires medical attention following an incident involving radiation. Initial tests on mice found that the technology only requires a drop of blood, measures radiation dose in minutes, and yields results up to seven days after exposure.

The technology was co-developed by scientists from Berkeley Lab and Stanford University, with help from researchers from the Armed Forces Radiobiology Research Institute, UC Davis School of Medicine, and the Methodist Hospital Research Institute’s Center for Biostatistics.

Currently, the most common way to measure radiation exposure is a blood assay that tracks chromosomal changes after exposure, or simply to watch for the onset of physical symptoms. But both methods take several days to provide results, which is far too long to identify people who need immediate treatment.

The researchers at Berkeley had already identified more than 250 proteins that change after exposure, and can serve as biomarkers but they needed a platform that puts these biomarkers to use. At Stanford, researchers had pioneered magnetic nanoparticles and giant magnetoresistive sensors for bio-detection of nanoscale objects such as proteins.

Together, they created a small chip with 64 magneto-nanosensors and a chip reader that connects the chip to an electronic circuit board, and can be linked to a laptop or smartphone for easy readout. Their proof of principle test matched results obtained via a widely used molecule-detection test called an ELISA assay. It also worked up to seven days after exposure.

The researchers plan to add antibodies for additional proteins to the chip so it can detect the presence of even more biomarkers.