New Microfluidic Chip Could Mean Earlier Disease Diagnosis

August 9, 2017
Kevin Hattori

Proteins are one of the most important classes of biomarkers – biological molecules indicative of a disease or health of an individual. Protein detection is critical in a wide variety of tests that include the diagnosis of malaria, detection of a cardiovascular event, cancer screening and monitoring, and more.

Federico Paratore

Now, a joint team from the Technion and IBM Research in Zurich has improved the sensitivity of protein detection in immunoassays by more than 1,000-fold, when compared to standard immunoassay implementation. The team’s method – which appears on the cover of the peer-reviewed journal Analytical Chemistry – is based on a simple piece of hardware: a microfluidic chip containing flow channels the width of a human hair.

High sensitivity in detection is particularly important when protein biomarkers are present in extremely small numbers, as is the case in the early stages of a disease. The team’s approach might one day enable simple devices capable of analyzing small samples (such as a drop of blood), replacing the large and sophisticated laboratory equipment that is currently required.

“We use an old focusing technique called isotachophoresis (ITP) in a new way,” says Assistant Professor Moran Bercovici, of the Technion Faculty of Mechanical Engineering. “Using a combination of electric fields and specialized chemistry, we collect proteins into a tiny volume and precisely deliver them to react with detection antibodies patterned on the surface of the microchannel.”

“We essentially cheat the detector,” says Federico Paratore, a joint PhD student between the groups, and the lead author on the work. “We present a protein concentration that is 10,000-fold higher than in the original sample to a standard detector, and get the detector to respond accordingly.”

Illustration of an immunoassay

The test is a simple one, as demonstrated by Paratore. A few drops of the sample are introduced into the microfluidic chip, and an electric field is turned on. The proteins are compressed to a volume of approximately 50 picoliters – about 1 million times smaller than the volume of a human teardrop, and the result is visible within a few minutes.

Paratore is part of a joint European Union project, Virtual Vials, and works across both sites, combining the strengths of the Technion’s team in electrokinetics and fluid mechanics with IBM-Zurich’s expertise in microtechnology and diagnostics. At the Technion, Paratore collaborated with Tal Zeidman-Kalman and Tally Rosenfeld, who are co-authors of this paper.

“The elegance of this approach is in its simplicity, and of course the immense enhancement in assay sensitivity that could be applied to a range of immunoassay,” says Dr. Govind Kaigala, scientist at IBM Research in Zurich. “We strongly believe such a technology will help to fill the gaps in existing immunoassay technology, and be applied directly to biological samples such as blood, saliva, or urine.”

The Technion-Israel Institute of Technology is a major source of the innovation and brainpower that drives the Israeli economy, and a key to Israel’s renown as the world’s “Start-Up Nation.” Its three Nobel Prize winners exemplify academic excellence. Technion people, ideas and inventions make immeasurable contributions to the world including life-saving medicine, sustainable energy, computer science, water conservation and nanotechnology. The Joan and Irwin Jacobs Technion-Cornell Institute is a vital component of Cornell Tech, and a model for graduate applied science education that is expected to transform New York City’s economy.

American Technion Society (ATS) donors provide critical support for the Technion—more than $2 billion since its inception in 1940. Based in New York City, the ATS and its network of supporters across the U.S. provide funds for scholarships, fellowships, faculty recruitment and chairs, research, buildings, laboratories, classrooms and dormitories, and more.