A team at Worcester Polytechnic Institute has developed a new kind of liquid biopsy chip designed to spot cancer by fishing rare tumor cells out of a simple blood sample. Those cells, called circulating tumor cells or CTCs, break away from a primary tumor and travel through the bloodstream, making them a valuable early warning sign of disease and a possible window into how cancer is changing over time. The new device uses carbon nanotubes—tiny cylinder-shaped structures made of carbon—to help capture these cells with high purity while keeping them alive. That matters because many existing systems trap cells in narrow microfluidic channels, which can make them hard to remove and easy to damage before scientists can study them. By contrast, the WPI chip is transparent, so researchers can stain and examine captured cells directly on the device, and in some cases even grow them afterward in culture. The technology is the latest version of a platform that has been refined over several years through a collaboration involving WPI, the University of Massachusetts Medical School, and the University of Louisville. With a multi-well format built using semiconductor-style manufacturing methods, the chip is also designed with scale-up in mind, raising the possibility of broader clinical use. Project lead Balaji Panchapakesan says the system may now be ready for clinical trials, with the long-term goal of creating a point-of-care test that could help detect cancer at very early stages.
How the chip works
Liquid biopsy is the idea of learning about a tumor from materials it sheds into blood, rather than taking a piece of tissue through surgery or a needle biopsy. It is appealing because blood draws are less invasive, easier to repeat, and better suited for tracking disease over time.
The hard part is that CTCs are extremely rare. In a tube of blood, they can be vastly outnumbered by normal blood cells, so any device that hopes to catch them has to be both sensitive enough to find them and selective enough to avoid collecting too much background noise.
Why carbon nanotubes help
The WPI device relies on carbon nanotubes to create a surface that invasive tumor cells preferentially adhere to. In plain terms, the chip is engineered so the cells researchers care most about are more likely to stick, while many unwanted cells are less likely to remain attached.
That selective sticking is important because it improves purity, meaning a higher fraction of the cells captured are actually tumor cells rather than harmless blood cells. Higher purity makes downstream analysis easier and more reliable, whether scientists want to count cells, image them, or test them for molecular markers.
Keeping captured cells alive
One of the most striking features of the platform is that the cells it captures can remain viable, meaning alive and intact enough for further study. Many competing devices require cells to be removed from tight channels after capture, a step that can damage fragile cells or reduce their usefulness for later analysis.
Because the WPI chip is transparent, researchers can also stain the cells and inspect them directly on the device. Staining uses chemical dyes or labeled antibodies to highlight specific proteins or structures, helping scientists confirm whether a captured cell is likely to be cancerous and learn more about its behavior.
Built for scale and better counting
The latest version described in Lab on a Chip is a 76-element array of test wells built on glass and silicon wafers. Those are familiar materials in semiconductor manufacturing, which means the chip can take advantage of fabrication methods already used to make electronics at scale.
The multi-well design offers a practical advantage beyond manufacturing. By splitting a blood sample across multiple small wells, the system can make it easier to count attached tumor cells accurately, since each well holds only a small volume and is simpler to inspect than one larger, crowded chamber.
A long-running collaboration
This device did not appear overnight. It is the latest generation of a liquid biopsy platform that has been under development for several years in the Small Systems Laboratory at WPI, led by Balaji Panchapakesan, a professor of mechanical engineering.
The work also involved collaborators at the Department of Neurological Surgery at the University of Massachusetts Medical School and the James Graham Brown Cancer Center at the University of Louisville School of Medicine. That kind of partnership matters because developing a diagnostic tool requires expertise not only in engineering, but also in cancer biology, medicine, and clinical testing.
Why This Matters
If this chip performs well in clinical settings, it could help push cancer testing toward something faster, less invasive, and potentially more accessible. A blood-based test that can detect tumor cells early would be especially valuable for patients who need monitoring over time, since repeated tissue biopsies can be expensive, uncomfortable, and sometimes risky.
There is also a deeper scientific benefit. If captured CTCs stay alive and can be cultured, researchers may be able to study how an individual patient’s cancer is evolving, test how those cells respond to drugs, and learn why certain cancers spread. In other words, the chip is not just a detector; it could become a tool for understanding metastasis, the process by which cancer spreads to other parts of the body.
What comes next
Panchapakesan says he believes the current chip is ready for clinical trials, an important step in showing that the technology works reliably with real patients outside the lab. To move toward that goal, he is working with StrandSmart Inc., a Silicon Valley startup led by CEO Adrianna Davies, on a possible point-of-care device.
The vision is ambitious but clear: a simple test that could be used broadly to detect cancer at its earliest stages, when treatment is often most effective. Much work remains before that becomes routine medicine, but the WPI chip points to a future in which a small blood sample can reveal far more about cancer than was once possible.