ORONO — Microdroplet generators are devices that produce tiny, precise liquid samples used for large-scale drug testing, cosmetics, cell analysis and scientific research.
Producing these devices, however, requires specific conditions such as clean rooms, special equipment and laser ablation, all of which contribute to a high manufacturing cost. To address this, University of Maine researchers developed a more affordable alternative in partnership with paper products manufacturer Sappi North America.
“We wanted to make these microfluidic devices more accessible to labs that can’t afford these devices created by traditional methods,” said UMaine undergraduate biomedical engineering student and project lead Wyatt Fessler. “We can make microfluidic devices that function similarly to ones that are made in traditional methods, but in a mass-manufactured fashion. So it makes these devices very, very inexpensive compared to what you might normally find on the market.”
The team focused their design efforts around creating a reusable, mass-manufacturable device that users can easily assemble and disassemble for cleaning.
Sappi, which operates a plant in Westbrook, worked with researchers to produce low-cost channel patterns that are used in microfluidic devices to generate droplets at scale. These patterns exclude the designs and fabrication that make traditional devices more expensive.
“What we noticed was that Sappi could make patterns that were at a scale similar to microfluidic devices, and they can do it in a mass-manufactured way,” said Fessler. The team designed the channel patterns that Sappi then stamped into a substrate on a micron scale. “It was so cheap. These little patterns are about 2-by3-centimeters and hundreds of thousands can be made in an hour.”
Researchers were also able to prevent leaks in their generator design by incorporating polycarbonate layers and high hardness silicone layers. To ensure blockages could be easily cleaned, the team tested the device’s housing mechanism with agar, a gelatin alternative typically made of red seaweed, to evaluate blockages in the device and droplet size. Once the agar was cooled, the team was still able to disassemble, clean and reassemble the device with ease.
This research has also helped Fessler develop as a researcher, building confidence in a professional lab setting.
“I think that going into research, especially as an undergrad, was the best decision I made in my academic career,” said Fessler. “Research is not just about the knowledge you have. It requires a positive attitude, creativity and perseverance to be successful in this field.”
Fessler earned a fellowship from UMaine’s Center of Undergraduate Research for the project, which he conducted with his advisor and associate professor of bioengineering Caitlin Howell. Their team’s work was supported by grants from the National Science Foundation, the National Institutes of Health, National and Maine Sea Grant and the UMaine Flagship Fellowship.



