Scientists advance MRI technology to screen liquids at airports

An advance in magnetic resonance imaging technology may allow for a breakthrough for screening liquids at airport security, the Los Alamos National Laboratory said on Monday.

Scientists with Los Alamos added low-power X-ray data to the existing MRI technology to unlock a new way to detect dangerous liquids using a system known as MagRay. The goal of MagRay is to help airport security to distinguish between visually identical liquids.

"One of the challenges for the screening of liquids in an airport is that, while traditional X-ray based baggage scanners provide high throughput with good resolution of some threats, there is limited sensitivity and selectivity for liquid discrimination," Michelle Espy, the MagRay project leader, said. "While MRI can differentiate liquids, there are a certain class of explosives, those that are complex, homemade, or may have mixes of all kinds of stuff that are more challenging."

For instance, while a bottle of white wine would be perfectly safe an a commercial aircraft, a bottle of the similarly clear liquid nitromethane could be used to make an explosive. MagRay is able to distinguish between harmless and hazardous liquids with an easy operator interface.

The system examines a liquid through a three-dimensional MRI, while calculating its X-ray density and proton content. Larry Schultz, an engineer on the project, said that by using the three different measures, benign liquids and threat liquids are easily distinguishable.

"I am amazed at how good it works," Espy said. "We've been able to look at a really broad class of explosives, we've been able to look through all kinds of packaging, and we've unlocked a new parameter - proton content - that's not available to either X-ray or MRI alone."

The MagRay project is funded in part by the U.S. Department of Homeland Security's Science and Technology Directorate.