NIT Rourkela develops cost-effective, label-free biosensor for breast cancer diagnosis 

A group of researchers from the National Institute of Technology (NIT) Rourkela has developed a novel biosensor to identify breast cancer cells without the need for complex or expensive laboratory tests. The initiative was led by Professor Prasanna Kumar Sahu of the Department of Electrical Engineering, along with research scholar Dr. Priyanka Karmakar. The work has been published in the renowned journal Microsystem Technologies.

With a worldwide increase in life-threatening diseases, there has been mounting emphasis on the creation of point-of-care (POC) diagnostic devices and the assessment of biological markers. Cancer, especially, is still a significant public health issue, and cases of breast cancer have increased exponentially in India over the past few years.

Since breast cancer that is in its early stages can sometimes be asymptomatic, early diagnosis is essential for successful treatment. Diagnostics like X-rays, mammograms, ELISA testing, ultrasounds, and MRIs are currently used; nevertheless, these all generally necessitate sophisticated machines and well-trained staff—something that may not be found in rural or underdeveloped communities.

The COVID-19 pandemic only served to compound these challenges by diverting medical supplies, postponing screenings as well as treatments. This serves to underscore the necessity for effective, accessible, and cost-efficient diagnostic technologies that are simple to deploy even in resource-scarce environments.

To tackle this problem, Prof. Sahu's group has used a new approach based on the unique physical properties of cancer cells. Cancerous breast tissue is denser and has more water than non-cancerous tissue and responds in a different way to microwave radiation—a characteristic referred to as dielectric variation. These changes can be employed to identify malignant cells versus normal cells.

In order to leverage this principle, the researchers suggested a Tunnel Field Effect Transistor (TFET) biosensor. From simulations done using Technology Computer-Aided Design (TCAD), this device is highly effective at detecting breast cancer cells. FETs are common electronics devices, but their use for biological detection in this manner is revolutionary. The greatest benefit of the biosensor is that it operates without the inclusion of additional chemical labels or reagents.

Describing the mechanism, Prof. Sahu added, "We have developed a tiny cavity under the gate region of the transistor upon which a sample that replicates biological tissue is positioned. The sensor is then able to detect changes in electrical signals due to the properties of the sample, allowing it to identify if cells are cancerous or not. Cancerous cells such as T47D have a larger dielectric constant than non-cancerous cells such as MCF-10A, meaning the sensor is able to distinguish clearly."

Preliminary observations show that the sensor is very responsive to T47D cancer cells due to their density and permittivity. It also shows better accuracy in distinguishing malignant from non-malignant breast cells, a big leap from existing detection technology.

One of the impressive aspects of this new biosensor is the fact that it comes at an affordable cost. Compared to traditional diagnostic methods and even other FET-based biosensors, the TFET-based model is a significantly more affordable option. This is a promising aspect for its possible deployment in clinics, mobile testing vehicles, and even homecare facilities, where cost-effectiveness and simplicity are key.

Looking to the future, the NIT Rourkela team is looking for collaborations to initiate fabrication and clinical proof of the sensor, with hopes that this innovation could soon be pivotal in affordable, early breast cancer diagnosis throughout India and the rest of the world.