Researchers at the University of Notre Dame have developed a new automated device that can diagnose glioblastoma, a fast-growing, incurable brain tumor, in less than an hour. Glioblastoma patients typically survive 12 to 18 months after diagnosis.

The device uses a biochip with electrokinetic technology to detect biomarkers such as active EGFRs, which are common in cancers such as glioblastoma and are found in extracellular vesicles.

“Extracellular vesicles or exosomes are large nanoparticles secreted by cells with a weak charge. Our technology is designed to use these properties for diagnosis,” explained Hsueh-Chia Chang, a professor at Notre Dame and lead author of the study published in Communications Biology.

The researchers faced two major challenges: distinguishing between active and inactive EGFRs and developing a diagnostic tool to selectively detect active EGFRs on extracellular vesicles in blood samples.

To solve this problem, they developed a biochip with an affordable electrokinetic sensor the size of a ballpoint pen. Antibodies on the sensor bind to the extracellular vesicles, increasing the sensitivity and selectivity of the diagnostics.

Synthetic silica nanoparticles detect active EGFRs on these vesicles by attaching a high negative charge. When active EGFRs are present, a voltage shift occurs, indicating the presence of a glioblastoma. This method reduces interference that is often found in other sensing technologies.

Satyajyoti Senapati, a research professor at Notre Dame, said: “Our electrokinetic sensor can do things that other diagnostic methods cannot. We can use blood directly without pretreatment and our sensor is not affected by other particles, making it more sensitive for disease detection.”

The device consists of three parts: an automation interface, a portable device to perform the test, and a biochip. A new biochip is required for each test, but the device and interface are reusable. The tests take less than an hour and require only 100 microliters of blood. Each biochip costs less than $2.

Although the device was developed for glioblastoma, it could be adapted for other diseases as well. Researchers are studying its use in pancreatic cancer, cardiovascular disease, dementia and epilepsy.

Chang said: “Our method is not only suitable for glioblastomas, but we started it because this disease is fatal and there are no early detection tests. We hope that early detection will improve the chances of survival.”

Journal reference:

1. Maniya, NH, Kumar, S., Franklin, JL et al. An anion exchange membrane sensor detects EGFR and its activity state in plasma CD63 extracellular vesicles from patients with glioblastoma. Communications Biology. DOI: 10.1038/s42003-024-06385-1.