Scientists are developing a portable device that can measure a person's radiation exposure in minutes using radiation-induced changes in the concentrations of certain blood proteins. This image shows a magneto-nanosensor chip reader station, chip cartridge, and chip. (Credit: S. Wang)
Scientists are developing a portable device that can measure a person’s radiation exposure in minutes using radiation-induced changes in the concentrations of certain blood proteins. This image shows a magneto-nanosensor chip reader station, chip cartridge, and chip. (Credit: S. Wang)

Picture the scene of the Fukushima nuclear accident. The Daiichi nuclear reactors were hit by an earthquake of magnitude 9.0, then flooded by the resulting 15-meter deep tsunami which caused a nuclear meltdown and release of radioactive materials. Over 100,000 people were evacuated from their homes due to the threat of radiation contamination. Although no deaths occurred due to the nuclear accident, there was potential for mass casualties since radiation can induce immediate and persistent damage to internal organs.

In a large-scale radiological incident like the Fukushima nuclear disaster, emergency medical personnel need a rapid way to assess radiation exposure and identify those who require immediate care. This radiation-dosimetry technology needs to be sensitive, accurate, fast and easy to use in a non-clinical setting.

Local scientists have developed a small, portable device that can quickly test the level of radiation exposure victims have suffered in such radiological emergencies. This technology was developed by scientists from Berkeley Lab, Stanford University and several other institutions, as reported in a journal article recently published in Scientific Reports. The lead researchers were Dr. Shan Wang from Stanford University and Dr. Andrew Wyrobek from Berkeley Lab.

This new dosimetry device is a novel type of immunoassay. Immunoassays are chemical tests used to detect or measure the quantity of a specific substance in a body fluid sample using a reaction of the immune system. For example, a common immunoassay test for pregnancy measures the concentration of the human chorionic gonadotropin hormone in a woman’s blood or urine sample.

In order to measure a person’s radiation dose, the new device measures blood samples for the concentration of particular proteins that change after radiation exposure. Scientists, including those in Wyrobek’s group, have previously identified these target proteins as excellent biological markers for radiation dosimetry; blood exposed to radiation has a special biochemical signature.

But scientists needed more than just target proteins. They also needed an accurate, sensitive way to quickly measure the proteins’ concentrations in a few drops of blood. So at the heart of the new device is a biochip developed by Wang’s group. This biochip uses magnetic nanoparticles and giant magnetoresistive nanosensors, so it is more sensitive and faster than conventional immunoassay techniques.

The biochip system relies on a sandwich structure where a target protein is trapped between a capture antibody and a detection antibody. The capture antibodies are immobilized on the surface of the biochip sensor. When a drop of blood is placed on the biochip, those antibodies capture the target proteins and the other proteins are washed away. Detection antibodies labeled with magnetic nanoparticles are then added, forming a sandwich structure that traps the target proteins. When an external oscillating magnetic field is then applied, the magnetic nanoparticles generate an electrical signal that is read out. This signal measures the number of magnetic nanoparticles bound to the surface, and this indicates the number of target proteins that have been trapped.

They tested the biochip system using blood from mice that had been exposed to varying levels of radiation. These novel immunoassay results were validated by comparing them with conventional ELISA immunoassay measurements. Overall, the scientists demonstrated that the new biochip dosimetry system is fast, accurate, sensitive and robust. In addition, the whole system is the size of a shoebox so it is very portable.

“You add a drop of blood, wait a few minutes, and get results,” explained Wyrobek in a press release. “The chip could lead to a much-needed way to quickly triage people after possible radiation exposure.” Although the technology is still underdevelopment, hopefully it will be available before the next radiological accident or terrorist attack occurs.

New Portable Device Rapidly Measures Radiation Exposure 4 September,2013Jennifer Huber

  • Joanna Vargas

    When I began to read this article I actually couldn’t imagine that these people I’m Daiichi would undergo such a massive destruction from Mother Nature. A 9.0 magnitude earthquake followed by a 15 meter tsunami. I hope nothing but the best for these people. It’s also a great way to think about that people come together to try and find a way to measure radiation. There is always the best solution when people work together. This portable device is very handy and you can take it anywhere. It’s useful for doctors and nurses around the world when the next big emergency occurs. It will help and save may people in the future.

  • It’s a relief that there is a device for such a dangerous threat to humanity and nature, identifying if they have radiation or not. This is the kind of stuff I like to hear, especially when Japan’s Fukushima radiation is approaching the West coast of the United States. This device is very useful, since it is claimed that it is very fast and accurate- which is what we all need even in the case of having radiation among us.

    The only little problem is, to the fact this device is still underdeveloped. But still, knowing that this device works, it’s a relief to hear this kind of device made to help everyone of us.

  • Andrea Montes de Oca

    This machine that was created my Berkeley and Stanford students is a really smart way to try to help the radiation leak. There were many people that had to be evacuated from their home because of the contamination. The machine is honestly a great way to find out which people are more sick than others. It measures the amount of radiation that is in them. Obviously the ones that are more contaminated should be helped first since they will probably be the ones that have less time to live. I think it’s really sad that people in Japan should have to go through that process of evacuation. Those people will probably have a chance of being sick. In the article it says that they need a fast resolution to this problem. This machine that was invited could be the answer to their problems in the future. Immediate care is important for those who are sick, and this machine is honestly the answer. In order to get this under control we need to make a plan and do it fast. Berkeley and Standford have created the solution and now it’s knowing how to use it to make it an advantage.

  • Kenny Lazaro

    I feel that this device will be very useful in the future. It is a quick way to determine if one is exposed or not. In emergencies, this device could save many lives. The people that are exposed could receive treatment immediately. Also, the device seems easy to use that anyone could use it. The device’s portability makes it easy to transport and carry as well. Doctors could carry multiple copies to help a significant amount of people. I really like how accurate device is, despite its size. It could maybe even be used in quick succession because it takes only a few minutes. In a disaster such as an earthquake, this device would prove to be extremely useful. I really hope that the device is ready before a disaster occurs. It would help a lot of people after a disaster.

  • guramrit virk

    I feel like this tool is very helpful, because it can help people know if they are in safe environment. If they aren’t, they can know that they need to evacuate it as quickly as possible. This tool is also very reliable, because it has been tested multiple times and it has been proven to be fast and accurate. The tool is also very small so it portable. It is also large enough as to where you would have some difficulty losing the tool. It also helps medics identify the people who are suffering more from radiation than others. It also is easy for most people to use. This device can also help doctors identify people suffering from radiation fast and easily. They could just take the blood samples rather than the process they would have to go through when a person is entered into a hospital.

  • Ever Galvez

    Evacuating homes because of radiation, that’s insane! Hopefully this device helps us out and does get the measurements of radiation. I Can’t believe how a 9.0 hit Japan and destroyed buildings letting go some radiation and on top of that a tsunami coming in and flooded the place taking all the radiation into the ocean and into the cities! Thank fully “The lead researchers were Dr. Shan Wang from Stanford University and Dr. Andrew Wyrobek from Berkeley Lab.” made a device that will now help us view how much radiation is around by a blood sample of a human or animal. In emergencies this device will gather the information and let the doctor how critical the situation is. This Device will be helpful in the next years because of all the other radiation in the world not just the one coming from Japan.


Jennifer Huber

Jennifer Huber is a medical imaging scientist at the Lawrence Berkeley National Laboratory with more than 20 years of experience in academic science writing. She received her Ph.D. in Physics from the University of California Santa Barbara. She is also a freelance science writer, editor and blogger, as well as a science-writing instructor for the University of California Berkeley Extension. Jennifer has lived in the San Francisco Bay Area most of her life and she frequently enjoys the eclectic cultural, culinary and outdoor activities available in the area.

Read her previous contributions to QUEST, a project dedicated to exploring the Science of Sustainability.

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