Project Lead(s): Frédérique Deiss
Issue
About 2.2 million people die from infectious diarrhea every year, the majority being children below the age of five, in developing countries such as Kenya and India.
Approximately 88% of diarrheal disease worldwide is attributed to the contamination of drinking water by microbial pathogens. Presence of pathogens (such as Escherichia coli O157:H7) in food and water has a devastating impact on health worldwide but, in remote locations and developing countries, quality monitoring is more difficult, due to the lack of infrastructure and poor testing.
Solution
The project involved the design of a paper-based device for the culturing and electrochemical detection of bacteria in food and water for use in low-resource settings.
The team also worked to combine electrochemical quantification and bacterial culture capabilities in one fully-integrated platform.
Use of electrochemical impedance spectroscopy (EIS) was explored because of its potential for sensitive and specific detection of bacteria, even in samples with a complex matrix (such as raw milk).
The approach involves comparing the electrochemical characteristics of the electrodes before and after adding and culturing the bacteria.
The devices developed are easy to fabricate and assemble, and can be incinerated after use to prevent contamination.
Outcome
Over the grant period, the team assembled more than 500 devices.
Four successive prototypes of the electrochemical paper-based devices were designed, fabricated, tested in the laboratory and modified to produce an enhanced version.
The fourth electrochemical prototype that was developed displayed good electrochemical properties, as verified by the typical techniques used for characterization in the field (electrochemical impedance spectroscopy and cyclic voltammetry).
Fabrication of the devices was done mainly by high-school students and demonstrated the ease of assembly by minimally trained personal.
Some in-field tests of water in India were conducted, comparing water from different sources and conditions in Mehsampur, Jallowal and Jalandhar, Punjab.
The results proved that in-field handling of the devices was convenient and that an incubator was not required for culturing bacteria at the concentrations found in the water onsite.
Knowledge of the project has been disseminated widely in conference presentations.