A high school sophomore’s science fair project could help to transform the way health inspectors and the food industry go about detecting E. coli bacteria.
Under the direction of University of Hawaii scientists, Ariana Kim, 16, of St. Andrew’s Priory School for Girls successfully demonstrated how a microwire sensor could be used to accurately detect the potentially deadly bacteria within a half-hour, significantly faster than the 12-hour method commonly used.
Soojin Jun, a UH associate professor of food engineering who mentored Kim, said the project to which Kim contributed could have far-ranging benefits.
"The presence of pathogenic bacteria in our food and water is a major concern in the food industry because of its critical impact of public health and our economy," Jun said. "Therefore, it is important to develop rapid early-detection tools to minimize the occurrence of foodborne pathogens.
"Our biosensor research shows great potential for rapid, sensitive and simple detection," Jun said. "Our future vision is to be able to integrate the developed microwave sensor technology into a portable device for simultaneous detection of pathogens."
Jun met Kim at a science fair two years ago. Impressed by a project she had developed involving foodborne pathogens and taken with her "passion for research," Jun invited Kim to work with his UH graduate students, who had developed the microwire biosensor for the detection of foodborne pathogens.
Braving her way through a crash course in advanced microbiology and micro-bio sensors, Kim said she devoted her after-school hours and weekends to working with Jun and graduate student Kara Yamada.
Kim’s contribution involved working with a gold-tungsten microwire immobilized with anti-E.coli-antibodies and charged with electricity to capture E. coli cells.
Kim said her initial experiments were unsuccessful due to problems with the level of electricity used. However, after experimenting with lower levels of electricity, Kim found that the detection system was capable of quickly, accurately (99.5 percent) and specifically detecting E. coli in liquid samples.
The experiment became the basis for Kim’s award-winning entry in the 2013 Hawaii State Science and Engineering Fair.
Kim who, among other things, is also captain of her school’s debate team and a participant in the Model U.N. program said she intends to continue developing her project.
UH is pursuing a patent for the technology.