HZDR team introduces novel pathogen detection approach

Various possibilities and mechanisms exist for detecting pathogens in body fluids. One option that Dr. Baraban investigates at the HZDR-Institute of Radiopharmaceutical Cancer Research is the detection using field-effect transistors (FETs) from the realm of electronics. The operating principle is simple: a defined electrical current flows from A to B.

This current can be regulated by the electrical potential on the surface of a gate, which functions like a precise, continuous valve. Disease-relevant biomolecules bind to the gate surface and thereby change the electrical potential and therefore the current as well. If there is no significant change in the current, no biomolecules have bound to the sensor surface. On the other hand, a change in the current means that disease-related molecules can be detected on the sensor surface.

These biosensors can be designed to specifically detect different biomolecules. Different pathogens cause different electrical potentials and therefore different currents. Cancer cells cause different currents than, for example, a flu virus.

Traditionally, FET-based biosensors are not reusable, increasing costs and environmental impact. Baraban's team addressed this issue by developing extended gates, allowing for multiple uses of the transistor. Additionally, they enhanced sensitivity using nanoparticles to amplify voltage signals, resulting in improved detection capabilities.

But that’s not all. The team thought even further ahead and took on another challenge: “We, of course, would like this system to carry out several analyses at the same time.” The researchers succeeded in developing extended gates with thirty-two test pads. Baraban explains, “This means that a sample can be tested simultaneously on each of the pads for a different pathogen.”

The scientists first demonstrated the operating principle using interleukin-6 (IL-6), a molecule responsible for communication between immune cells. “Whether it’s a simple cold or cancer, the concentration of IL-6 changes. Different diseases as well as different stages of a disease produce different clinical pictures. That is why IL-6 is very well suited as a marker.”

The newly developed test system offers rapid detection of various pathogens, making it valuable for monitoring disease progression and predicting outcomes. This technology holds promise for applications such as monitoring cancer immunotherapies and predicting the severity of viral diseases like the flu or COVID-19. Compared to existing methods, this approach is more cost-effective and efficient, making it attractive for commercialization.

MEDICA-tradefair.com; Source: Helmholtz-Zentrum Dresden-Rossendorf (HZDR)