Digital microfluidics: how it works
Shih and his team developed DMF technology that can automate the synthetic biology process of "design-build-test-learn." Digital microfluidics involves miniaturized “lab-on-a-chip” devices.
Normally the size of a credit card, they are used to integrate several laboratory functions onto a single chip as small as a few nanolitres of fluid.
“By manipulating very small volumes of fluid on electrodes using voltage, we have a powerful tool that allows us to perform several medical tests in one shot, and address challenging problems in health care,” says the founder of the Shih Microfluidics Laboratory.
Our device will radically speed up lab analysis and research.
Steve Shih
Cancer research is one example of how DMF technology can be applied. Researchers can take a sample of cells — usually a tiny droplet of cells that researchers believe are going to help us understand cancer better — and put them directly on the DMF device with an array of electrodes.
“Trying to obtain cells related to diseases like cancer are very precious. It's difficult to grab lots of them, so working at this small scale really helps us,” says Shih. “We can put the cells on the DMF device, then interrogate or mix these cells with drugs in liquid form to determine the effects of the drug on the cancer cells— thus, the necessity to be able to move liquids.”
A camera that detects movement failure
Sometimes, however, the droplets don’t move. Previously, there was no online way to track when the droplets didn’t respond to the electrodes. Shih’s new system solves that problem, charting the movement of many droplets at once.
“Our system consists of integrating open-source electronics with a camera and a off-the-shelf lens for acquisition of the images that will be used to detect droplets on the device,” says Shih.
“We also created an algorithm that uses a Hough transform to detect a variety of droplet sizes and to detect singular droplet dispensing and movement failures on the device. Then we can reapply the voltage, if desired.”
Shih aims to create a more accessible alternative to automation systems that now cost at least $2 million dollars.
“Our lab is using this system to understand the mechanisms of cancer -- that is when we know we have really made a difference” Shih says.
Read the study: Image-based feedback and analysis system for digital microfluidics.
Listen to Shih describe his work on Concordia's 2067 podcast series.
Learn more about the Shih Microfluidics Laboratory at Concordia.