New lab-on-a-chip technology developed by U of T graduate students attracts researchers from around the world

July 17, 2014 by Sean Bettam - A&S News

The opportunity to learn about a revolutionary technology that could significantly advance microfluidics research brought scientists from Brazil, England, Taiwan and elsewhere to Aaron Wheeler’s chemistry laboratory this week. They came to learn how to use DropBot, a technology that bolsters microfluidics by adding a digital component.

Microfluidics — the technology behind lab-on-a-chip — involves the manipulation of small samples of fluids at the sub-millimetre scale. In digital microfluidics, droplets are moved, mixed, separated or otherwise processed. The technique is used in medical diagnostics, chemical synthesis, tissue engineering and cell culture analysis and, in the case of lab-on-a-chip, does several functions at once on a portable laboratory-quality device.

The DropBot lab-on-a-chip system was developed by brothers Ryan and Christian Fobel, both researchers in Wheeler’s lab. Ryan, a PhD candidate in biomedical engineering, masterminded the hardware while Christian, a research associate, developed the software. They have since made the technology available for use by anyone using the open-source model.

“Making this available to others working in microfluidics is inspiring,” said Norwegian University of Science and Technology nanophysicist Armend Håti. “Instead of trying to build something that already exists, and learning from our own mistakes, we can learn from the mistakes of others and maybe improve it ourselves.”

Moving research forward is the principle that drove the developers to organize the meeting.

“This is a really good way to advance microfluidics research quickly,” said Ryan Fobel. “The more people we can get using this technology, the better for all of us.”

With DropBot, droplets of fluid navigate digitally across a surface. Viewed on a computer screen, the process resembles a chessboard as drops are pushed from one square to the next by computer-controlled signals. Adding this digital element to microfluidics provides a level of control never before seen in the field, with the ability to program smart sequences that tell the droplets where and when to move during testing. The electronics can be ordered online from various printed circuit board manufacturers, and all other necessary hardware is created with 3-D printing and laser cutting templates, which makes DropBot accessible to anyone who wants to build, and customize, their own version.

The U of T team realized they needed to host a meeting to share DropBot after fielding inquiries when presenting it at several international conferences.

“We knew that others were doing experiments that could benefit from this, and that we could benefit from feedback to steer our development,” said Christian Fobel. “We invited other research groups figuring that with no commercially available products to do this work, we should start collaborating.”

Mindy Simon, a postdoctoral research associate investigating cancer diagnostics at Stanford University’s School of Medicine, noted that the system is the only one of its kind that she’s aware of.

“If I can get it up and running, I’ll be using it a lot,” she said.

Wheeler, who holds the Canada Research Chair in Bioanalytical Chemistry in the Department of Chemistry, the Institute of Biomaterials and Biomedical Engineering and the Donnelly Centre for Cellular and Biomolecular Research, is excited about the novel aspect of both the technology itself and the way his students are leading its development through the open source model.

“I think we’re really on the cutting edge of something here,” said Wheeler. “There are a few of us working very hard, demonstrating some interesting ideas. But for the technique to really explode and be widely used we need to get it in to the hands of more people. Until now we haven’t had a chance to see what it can really do.”