What if the same yeast that made popular beers could become an effective type of cancer-tracking tool? Researchers from Purdue University are making that a reality by developing a way to use yeast to detect deadly radiation.
However, in true beer-related fashion, they're building "microbreweries" rather than ovens to cultivate the yeast. These microbreweries exist within low-cost materials disposable patches of freezer paper, aluminum and tape.
Users would put a drop of water on the patch to activate the yeast and let the yeast work its magic. Ideally, the researchers said, the patch would one day connect to a smartphone or other device.
This would give users a readout with minimal waiting time. "You would use the badge when you're in the lab and recycle it after you've checked your exposure by plugging it into a device," said Manuel Ochoa, a postdoctoral researcher in Purdue's School of Electrical and Computer Engineering.
Protecting radiologists from harmful exposure
This technology would be particularly helpful to radiology workers in hospitals and medical centers who consistently expose themselves to low doses of radiation during the day. Protective gear does help them within the day-to-day range of exposure but their bodies still absorb some of the radiation, the researchers said.
As the Purdue team pointed out, radiologists and other jobs dealing with gathering things like X-rays are at a higher risk of exposure. Radiation going even slightly above guidelines can have cancer-triggering effects.
"Currently, radiology workers are required to wear badges, called dosimeters, on various parts of their bodies for monitoring their radiation exposure," said Babak Ziaie, Purdue professor of electrical and computer engineering.
"They wear the badges for a month or two, and then they send them to the company that made them. But it takes weeks for the company to read the data and send a report back to the hospital. Ours give an instant reading at a much lower cost," Ziaie continued.
The power of yeast
The key to the project lies in the yeast. Yeast quickly reacts to radiation and dies and the higher the dosage, the higher the percentage of yeast cells that die.
To activate the yeast, users simply add water. The cells that are still alive release carbon dioxide -- a process brewers are familiar with because it's the same reaction during the fermentation process for making beer.
Carbon dioxide bubbles at the surface of the patch, forming ions. Those ions make the yeast conduct electrical current. This allows researchers to hook up the bandages to electrical equipment to get a readout.
"We use the change in electrical properties of the yeast to tell us how much radiation damage it incurred. A slow decrease in electrical conductivity over time indicates more damage," said Rahim Rahimi, Purdue postdoctoral researcher in electrical and computer engineering.
The readout translates into rads -- the same units of measurements used by the Occupational Safety and Health Administration for radiation. Human skin should only be exposed to 7.5 rad over a three month period.
Using the patches, researchers can detect as little as 1 millirad. This makes the badges comparable to standard radiation badges on the market, but at a significantly cheaper production cost.
"For yeast, it seems that radiation primarily affects the cell walls of the membrane and mitochondria," Ochoa said. "Since biologists are already familiar with yeast, then we're more likely to understand what's causing the biological effects of radiation in organic matter."
The study was published in the journal Advanced Biosystems.
Via: Purdue University