New microfluidic device could shed light on cell growth, regrowth, and development

Throughout the human body, neighboring cells can exchange ions and small signaling molecules to share information with one another. In non-neural cells, this communication is often related to cell growth, regrowth, and development. Studying the gap junctions through which cells communicate can help researchers understand cell network dynamics.

Associate Professor Valencia Koomson of the Department of Electrical and Computer Engineering is working with an interdisciplinary Tufts team to develop a microfluidic device that can electrically measure the gap junction to better understand connections between cells. The team includes first author and recent PhD graduate Joel Dungan and Koomson, both of the Department of Electrical and Computer Engineering and staff scientist Juantia Matthews and Vannevar Bush Professor Mike Levin, both of the Department of Biology. Their process is outlined in “A microfluidic sucrose gap device for electrical measurement of gap junction connectivity” and was featured on the cover of Review of Scientific Instruments. 

Measuring intercellular connectivity can provide a wealth of information but gathering accurate measurements can be challenging. Common methods such as patch clamping are difficult, invasive, and can only capture one cell pairing at a time which means they might miss larger patterns across cell networks. Other techniques such as dye diffusion lack accuracy. Koomson and team developed a proof-of-concept device that uses a different method – the micro level sucrose gap technique – to electrically measure the gap junction connections between cells.

The sucrose gap technique involves three chambers that are each completely sealed from one another to prevent any diffusion. The chamber in the middle is filled with a non-conductive sucrose solution, while the two outer chambers hold conductive solutions. A sample is placed across all three chambers to measure the electrical connectivity between the cells. For example, if a drug is introduced to the central chamber, researchers can measure how it affects electrical signals traveling through the cell sample. Koomson’s microfluidic device employs this technique using small amounts of fluid on a custom chip fabricated at the Tufts Micro and Nano Fabrication Facility.

More research is needed to interpret network signaling and further improve the device, but their work represents an important first step towards understanding intercellular connectivity. Reliable electrical measurement of gap junction connectivity could also provide key insight into how cells grow, develop, and heal. With further development, the device could improve artificial tissue and organ growth, as well as advance the treatment of abnormal growth, including birth defects, degenerative diseases, aging, and cancer.

Koomson's other research interests include the design of silicon-based mixed-mode VLSI systems (analog, digital, RF, optical), analog signal processing, and optoelectronic system-on-chip modeling and integration for applications in optical wireless communication and biomedical imaging. She is the director of the Advanced Integrated Circuits and Systems Lab at Tufts.

Learn more about Associate Professor Valencia Koomson.