The product of a combination of world-class microelectronics and molecular biology promises to help Idaho ensure that its agricultural products maintain a premium reputation for quality and safety. The product is a cutting edge biosensor, being developed by an interdisciplinary UI team and may, when finished, also aid groups as diverse as medical professionals and defense forces.

The team’s goal is to develop a biosensor capable of rapidly and accurately testing food before and during processing to detect threats to public health. The team is working to develop transistors that will recognize specific organisms or the toxins they produce. The microelectronic device would provide rapid, accurate and reliable tests of food as it is processed. It might look like an electronic thermometer that many cooks now use, exceptinstead of a digital temperature readout it would show the presence, and concentration, of pathogens or toxins.

The first efforts to build a biosensor will focus on detecting Staphylococcus aureus, a ubiquitous germ that can contaminate a variety of foods and cause life-threatening infections. Studies estimate that more than half of all people carry staph without ill effects. When staph bacteria begin producing enterotoxins, hazards escalate. Livestock producers know it as a principal cause of mastitis, which costs dairy producers billions of dollars of losses annually. This effort to directly combine transistors and biological molecules will push the current limits of technology and knowledge for the engineers and the biologists involved. The UI team already has demonstrated its abilities to pioneer new frontiers in both disciplines. Project directors include: Larry Branen, a food scientist and the university’s vice president of Outreach and College of Agricultural and Life Sciences dean, who leads the project. Gary Maki, director of the UI Center for Advanced Microelectronics and Biomolecular Research based at the Post Falls Research Park, who leads the project’s technology development side. Maki has built a strong working relationship with NASA based on his ability to design and deliver unique microchips essential to space missions. In fact, 20 of the next 21 satellite missions planned by NASA use chips designed by Maki’s team.

Greg Bohach, Microbiology, Molecular Biology and Biochemistry Department head and director of the UI Center of Biomedical Research Excellence to Study the Molecular and Cellular Bases of Host-Pathogen Interactions, who leads the microbiology component. The center was established with a $9.7 million grant from the National Institutes of Health two years ago. Tom Bitterwolf, professor of chemistry, is providing the organic chemistry expertise that interfaces molecular substances with transistor structures.

Wusi Maki, an assistant professor of microbiology, serves as co-project director in molecular biology and the molecular biology liaison to the electronic designers.

The team has already begun to surmount one obstacle, a sizeable language barrier between the disciplines. Wusi Maki stepped into the gap to help microelectronic engineers understand molecular biology and organic chemistry, while she learns to design transistor-based circuits that interface with molecular structures.

“What I see is the stimulation of people on all sides of this,” Branen said. “It’s synergistic reactions happening and you’re increasing the capability to address these problems by the interaction between the two groups.”

In an age when genetics has become essentially a real-time exercise made possible by sophisticated testing that can identify single genes or map entire genomes, speed and accuracy remain major challenges. Meeting these challenges is particularly important today given the evolution of the nation’s food production system, where massive beef processing plants mean that a small problem early in the hamburger production process, for example, can soon expand to affect thousands of consumers.

The project’s initial funding, $600,000, reflects that concern and was provided by the USDA Cooperative States Research, Extension, and Education Service with assistance from Sen. Larry Craig, RIdaho. Branen said he expects support for the still-new project to broaden.

The theory behind the UI quest for a rapid and accurate sensor to provide real-time results is essential to the Hazard Analysis Critical Control Point principle that governs modern food safety protection, Branen noted. Efforts to ensure safe hamburger, for example, require inspection and testing of carcasses when they first enter the plant. As beef is cut and ground, further testing is conducted and more tests are made as the final product leaves the plant.

The practice now lags behind the principle at times because of current technological limitations. Conventional microbiological tests can take at least a day to complete, then reliability and accuracy can vary widely. More sensitive genetic testing can precisely identify the organism involved but is both expensive and vulnerable to false positives. The new technology under development at UI would at least reduce the problems related to current practices. Testing would become rapid, accurate, reliable, and inexpensive. Gary Maki’s group also believes the new transistors in the devices would have the sensitivity to detect extremely small concentrations of toxins. The payback from this initial effort could be substantial. Some 1.5 million Americans suffer staph food poisoning each year. The economic toll is estimated at $1.2 billion.

The project focused on staph, Branen said, for many reasons in addition to its health and economic consequences. The university’s expertise in studying the bacterium as an economic threat to the dairy industry worldwide and that bacterium’s ability to infect people was also primary among the considerations. Bohach and other members of the MMBB faculty are leaders in identifying S. aureus isolates that produce toxins and underwhat conditions, and the ways the bacterium can invade and infect cells. Gary Maki’s team will apply its expertise with ultra low power chips and very large scale integrated processors. Both properties are as essential to the goal of a versatile biological testing device as they are to use on the spacecraft that Gary Maki’s team helped outfit. Gary Maki said, “It is amazing to discover unique technology developed for NASA to allow electronics to fly in space can be used in a biosensor involved in food safety.”

Other technical challenges include expanding knowledge about the electrical properties of biological materials to give engineers enough information to design the needed electronic circuits. Once the technology is developed for staph, Branen predicted the basic design would apply to a broad range of other disease organisms. The end result will be a device that can feed data to a single computer or the Internet, providing a real-time safety monitoring system.