Chip diagnoses infection in minutes, not days

U. TORONTO (CAN) — An electronic chip can analyze blood and other clinical samples for infectious bacteria faster than ever before.

Life-threatening bacterial infections cause tens of thousands of deaths every year in North America. Current methods of culturing bacteria in the lab can take days to report the specific source of the infection, and even longer to pinpoint the right antibiotic.

The new technology identifies the pathogen in a matter of minutes, and can look for many different bacteria and drug resistance markers in parallel, allowing rapid and specific identification of infectious agents.


“Overuse of antibiotics is driving the continued emergence of drug-resistant bacteria,” says Shana Kelley, a researcher at the University of Toronto and a senior author of the study published in Nature Communications. “A chief reason for use of ineffective or inappropriate antibiotics is the lack of a technology that rapidly offers physicians detailed information about the specific cause of the infection.”

Many infections are resistant to first-line antibiotics and there is an urgent, unmet need for technologies that can allow bacterial infections to be rapidly and specifically diagnosed, she says.

The researchers developed an integrated circuit that could detect bacteria at concentrations found in patients presenting with a urinary tract infection.

The chip reported accurately on the type of bacteria in a sample, along with whether the pathogen possessed drug resistance,” says first author Brian Lam, a PhD student in chemistry.

One key to the advance was the design of an integrated circuit that could accommodate a panel of many biomarkers.

“The team discovered how to use the liquids in which biological samples are immersed as a ‘switch’ allowing us to look separately for each biomarker in the sample in turn,” says Ted Sargent, a senior author of the report.

Source: University of Toronto