Chip Identifies Bacterial Infection In Minutes, Not Days
Co-senior author Shana Kelley, of the department of Pharmacy and Biochemistry at U of T, and colleagues, write about their work in a 12 June online issue of Nature Communications.
Kelley says in a statement that drug-resistant bacteria are emerging all the time because antibiotics are either over-used or not used appropriately.
But this is not necessarily due to deliberate misuse or sloppy practice: a major factor can be the length of time it takes to find out exactly what is behind the infection and just as importantly, which drugs to treat it with.
It can be a race against time, and if time runs out, doctors have to make potentially life-saving decisions based on incomplete information.
What is missing is a "technology that rapidly offers physicians detailed information about the specific cause of the infection," says Kelley.
Electronic devices that give a simple readout, based on highly sensitive and specific diagnostic tests that use small panels of biomarkers, already exist.
But what is needed is a device that can "interrogate samples for many dozens of biomarkers," write the authors in their background information.
One of the barriers to developing such a device is how to design an inexpensive platform that can accommodate large arrays of electrode-based sensors.
With this challenge in mind, Kelley and colleagues set out to develop and test such a device.
They already knew the way to go was to use electronic chips, like the ones used for small panels of biomarkers, but somehow they needed to change the design so the chips could cope with what they describe as "highly multiplexed electrochemical sensing" in order to screen for many biomarkers at the same time.
And they found a way to do just this, using "solution-based circuits formed on chip".
They designed and tested such a chip that could detect bacteria at concentrations found in patients with a urinary infection.
"The chip reported accurately on the type of bacteria in a sample, along with whether the pathogen possessed drug resistance," say first author Brian Lam, a Chemistry PhD student at U of T.
The solution-based circuit concept allowed the chip to use the liquids in which the patient samples are immersed as a "switch", so the team could look separately for each biomarker in turn, says co-senior author Ted Sargent, from the department of Electrical and Computer Engineering at U of T.
"The solution-based circuits switch the information-carrying signal readout channels and eliminate all measurable crosstalk from adjacent, biomolecule-specific microsensors," note the authors.
"We also show that signature molecules can be accurately read 2 minutes after sample introduction," they add.
Ihor Boszko, director of a Toronto-based business that develops in vitro diagnostics tools says the team's new concept could have significant practical implications.
It will enable rapid screening for multiple viruses or bacteria that produce similar symptoms, and:
"It also allows for simple and cost effective manufacturing of highly multiplexed electrochemical detectors, which will certainly have a significant impact on the availability of effective diagnostic tools," says Boszko.
The study is a good example of the kind of innovations that can occur when experts from different fields work together: in this case computer engineers, biologists, chemists, pharmacists, and more.
In another remarkable example of interdisciplinary teamwork, a study published early 2013 in the British Journal of Cancer describes how cancer researchers and astronomers put their heads together and adapted computerized stargazing techniques developed for spotting distant galaxies to identify biomarkers in tumors to determine how aggressive they are.
Recommended related news
"Solution-based circuits enable rapid and multiplexed pathogen detection"; Brian Lam, Jagotamoy Das, Richard
D. Holmes, Ludovic Live, Andrew Sage, Edward H. Sargent & Shana O. Kelley;
Nature Communications published online 12 June 2013; DOI: doi:10.1038/ncomms3001; Link to
Additional source: University of Toronto.
Visit our Infectious Diseases / Bacteria / Viruses category page for the latest news on this subject, or sign up to our newsletter to receive the latest updates on Infectious Diseases / Bacteria / Viruses.
Please use one of the following formats to cite this article in your essay, paper or report:
Paddock, Catharine. "Chip Identifies Bacterial Infection In Minutes, Not Days." Medical News Today. MediLexicon, Intl., 19 Jun. 2013. Web.
23 May. 2017. <http://www.medicalnewstoday.com/articles/262145.php>
Paddock, C. (2013, June 19). "Chip Identifies Bacterial Infection In Minutes, Not Days." Medical News Today. Retrieved from
Please note: If no author information is provided, the source is cited instead.
Contact our news editors
For any corrections of factual information, or to contact our editorial team, please see our contact page.
Copyright Medical News Today: Excluding email/sharing services explicitly offered on this website, material published on Medical News Today may not be reproduced, or distributed without the prior written permission of Medilexicon International Ltd. Please contact us for further details.