New Microchip Can Proficiently Sort Living Cells

Working together with scientists at the Brigham and Women's Hospital (BWH), researchers at the Massachusetts Institute of Technology (MIT) announce the development of a new microfluidic device, which can easily sort various types of cells from blood or other liquids.

The device has tremendous potential in medicine, or for biological research. Scientists are constantly looking for new ways to produce or separate specific types of cells from mixtures, so that they can have access to large amounts of research material.

Existing techniques work, but they are very time- and energy-consuming. The microfluidic device proposed by the new study would make short work of any task experts throw its way. One of its main advantages is that it can be used in a stacked arrangement.

This means that a stream of biological material could flow from one such device to the next. Each of the chips would be fine-tuned to trap and separate specific types of cells, while letting all other pass.

In order to do that, the tool uses cell rolling, a natural process that cells use to move around in the body. The same behavior can also be seen in immune system cells such as white blood cells. In inflammation, their motions are slowed down by modified endothelial cells lining blood vessel walls.

The endothelial cells produce a series of molecules that temporarily bind to the white blood cells, forcing them to literally roll on the vessel walls, and help heal inflamed areas. The exact same basic principle is applied in the new microchips.

Inside the devices, tiny channels are outfitted with various types of molecules, dedicated to slowing down varied cells. Each of these channels has a receptacle, through which the separated cells can be extracted. Each microchip is about the size of a postage stamp.

“We’re working on a disposable device where you wouldn’t even need a syringe pump to drive the separation. You could potentially buy a $5 or $10 kit and get the cells sorted without needing any kind of [additional] instrument,” says Rohit Karnik.

The expert holds an appointment as the d’Arbeloff assistant professor of mechanical engineering at MIT. He is also the author of a new paper describing the findings, which appears in the latest online issue of the esteemed journal Lab on a Chip.

“It’s really the ability to design molecules to separate cells of interest that will be powerful. There’s no reason to believe it cannot be done, because nature has already done it,” the expert concludes.