Smartphone Technology Used to Detect Contamination

Most tests for foodborne contamination are designed to detect one pathogen at a time. A test that could identify multiple pathogens in one step could dramatically improve efficiency of product safety testing—and that’s what scientists with the company Crystal Diagnostics, in conjunction with Kent State University and Northeast Ohio Medical University, claim that they’ve been able to do.

Using liquid crystals, a technology commonly used in smartphones, the Crystal Diagnostics MultiPath system can reportedly detect Listeria, E. coli, and Salmonella in a single test.

The test utilizes a “cassette” comprising two control cells and three test cells. An enriched sample from a food product is mixed with liquid crystals and either a single antibody or a cocktail of antibodies—depending on how many pathogens are being sought—and placed in the test cells. The cassette is then inserted into a reader. If the target pathogens are present, the antibodies will clump and distort the liquid crystal matrix. The “clumps” allow light to shine through the matrix, and an optical detector registers them as points of light on a dark background. Results are displayed on a handheld device such as an iPad within 30 minutes—far less than the usual 24 to 48 hours that is normal for many traditional methods.

The scientists who developed the system—Christopher Woolverton, PhD, director of the Center for Public Health Preparedness at Kent State University, Oleg Lavrentovich, PhD, of Kent State’s Liquid Crystal Institute, and Gary Niehaus, PhD, of the Northeastern Ohio Universities College of Medicine—claim that it significantly reduces false positives and negatives.

“This is groundbreaking technology in food safety testing. It’s reliable, it’s cost-effective, and it’s easy to use,” said Dan Minardi, Crystal Diagnostics’ president and chief technology officer. Crystal hasn’t published a price for the new technology, which will be in field beta testing over the next few months.