Microfluidics experts gather to share and explore ‘organ-on-a chip’ and ‘lab-on-a-chip’ technologies

November 28, 2024 by Chris Sasaki - A&S News

In October, scientists from around the world gathered at the MicroTAS conference in Montreal to share their expertise in microfluidics and related technologies. It was the first time in 26 years that the gathering was held in Canada and it attracted 1500 participants — a record number.

“The technologies featured at MicroTAS are powering so-called ‘organ-on-a-chip’ systems,” says conference co-chair, Aaron Wheeler. “These technologies will replace animal testing in drug development; enable wearable systems to detect markers in human sweat, skin and blood for continuous monitoring of health and disease; make possible point-of-care medical devices that can be used in the field; improve forensic analysis of evidence; and much more.”

Wheeler is a professor of analytical chemistry in the Department of Chemistry in the Faculty of Arts & Science, the Institute of Biomedical Engineering at U of T, as well as the Centre for Research and Applications in Fluidic Technologies (CRAFT) which is run by U of T and the National Research Council. Wheeler’s MicroTAS co-chair was David Juncker, a professor of biomedical engineering from McGill University.

Says Wheeler, “The conference is the premiere venue for discussions in this community of researchers, as we work together to develop the next generation of innovations for human health.”

Microfluidic devices allow researchers to control and manipulate tiny amounts of fluid with electrostatic signals, making it possible to precisely combine, split and mix tiny drops of fluid. As the commonly used term “lab-on-a-chip" suggests, it is like shrinking a full-size lab onto a device that can fit in your hand.

The MicroTAS agenda included hundreds of keynote addresses, presentations and posters.

One presentation featured research conducted by University Professor Eugenia Kumacheva from the Department of Chemistry and her colleagues. The work was described in their paper in the journal Advanced Materials, “Microfluidic Platform for Generating and Releasing Patient-Derived Cancer Organoids with Diverse Shapes: Insight into Shape-Dependent Tumor Growth.”

The team focused on micrometer-size aggregates of cancer cells, known as patient-derived tumor organoids, that are used in medical research to mimic organs or tissue. They used a microfluidic platform to form organoids with different shapes in order to study how shape affects tumor growth.

While spherical organoids have previously been formed, there’s been less success with non-spherical shapes. The team developed a “tumor-on-a-chip" platform with which they formed different-shaped organoids which could then be removed from the device for further analysis. The researchers found that cancer-active cells grew faster in regions of organoids that were highly curved.

According to Kumacheva, “This work empowers patient-derived cancer models, offering a valuable tool for in-depth analysis of cancer invasion and advancing fundamental cancer research and drug screening.”

Postdoctoral researcher Chiwon Lee presented the work he is conducting with colleagues under the supervision of University Professor Dwayne Miller from the Department of Chemistry.

Most microfluidic devices work on the scale of cells and tissue; but the goal of Lee and Miller’s research is to develop a nanofluidic device that works on the scale of biological molecules a thousand times smaller than the scale of microfluidics.

“The ultimate goal is to directly observe how DNA transforms into messenger RNA (mRNA), and how messenger RNA transforms into protein,” says Lee.

In order to view such processes, researchers use an electron microscope. But electron microscopes only work on samples that are frozen or in a vacuum chamber within the instrument. Because those conditions would render biological molecules inactive, Lee and Miller have devised a way to create a very thin layer of liquid water in which molecules like DNA and mRNA can be held and observed.

“Currently, we’ve had success in controlling the thickness of the liquid and imaging something inside it,” says Lee. “The next step will be to put some biological samples inside the liquid, then image and analyze their structures.”

Chemistry PhD student Anthony Yong shared the research he is conducting with Wheeler and collaborators from Sunnybrook Hospital. The team is developing the T-Bot, a device that uses AI and digital microfluidics to provide rapid blood typing capabilities.

Emergency room doctors often need to know a trauma patient’s blood type immediately in order to provide a critically needed blood transfusion. But blood typing typically requires large, sophisticated instruments — often located in a lab in another part of the hospital; what’s more, the procedure cannot necessarily be done on demand. In the face of such a delay, medical staff will often resort to using O-group blood which any patient can receive but which can be in short supply because of this trait.

The T-Bot will make it possible to determine a patient’s blood type directly, in a hospital emergency room, thereby allowing medical staff to administer the correct blood promptly.

“Our device uses digital microfluidic technology to automate blood typing — from mixing reagents to interpretation,” says Yong. “Our latest prototype is about half the size of a shoebox, something that any emergency room setting could accommodate.”

For Yong, the conference was more than just an opportunity to present research.

“It was a blast,” he says. “It was a fantastic community to be part of. It was great to see different perspectives, different techniques, all the different ways researchers around the world are approaching the same problems.”