Award for chip that separates bacteria from food

08-Dec-2014 - Last updated on 08-Dec-2014 at 10:14 GMT

The microfluidic chip allows the separation of bacteria from an unenriched sample in less than an hour, said Atencia

Related tags Polymerase chain reaction Bacteria

A disposable microfluidic chip used to separate bacteria from food samples has won a US award.

Javier Atencia, University of Maryland (UMD) Fischell Department of Bioengineering Research Assistant Professor, won the Best Inventor Pitch at the 2014 Professor Venture Fair.

Atencia said the disposable chip allows for the separation of bacteria from an unenriched sample in less than an hour, according to a media release about the event.

Bacteria separation

By separating the bacteria from the sample, specific strains can be identified by polymerase chain reaction (PCR) testing.

This is possible because the chip is designed to load and extract samples using pipetting making it easy for any lab technician to use and it allows onsite testers to carry out quick extraction in the field.

Atencia said while many of the pathogenic bacteria responsible for foodborne illnesses are known, and testing is routine, contaminated food still reaches the consumer.

Part of the problem may be the length of time required to test food samples for contamination using current sample pre-processing methods, he said.

Despite development of modern and fast detection methods, the time for testing takes one to two days, meaning most food with short shelf-life is sent to customers before it has been completed.

Pre-processing bottleneck

The bottleneck of pathogen testing is sample pre-processing, said Atencia.

“Test samples are often a complex mixture of small numbers of pathogens combined with large numbers of other cells, foreign DNA, and other solid particles.”

The presence of other constituents often interferes with the detection of pathogens so a bacterial enrichment step, where the sample is incubated with abundant nutrient media, is often required.

But this can take from 10 to 36 hours depending on the bacterial species and is the longest step in the testing process.

“Ideally, testing that can produce results within a single eight-hour work shift would allow results to be obtained prior to food being shipped to customers,” said Atencia.

The work was supported by the Office of Law Enforcement and Security (OLES) at the National Institute of Standards and Technology (NIST).