Researchers have developed a biosensor using metasurfaces to detect terahertz radiation, a development that enables early detection of skin sensor. The work is the result of a collaboration between Queen Mary University of London and the University of Glasgow. According to postdoctoral researcher at Queen Mary University Shohreh Nourinovin, traditional methods of detecting skin cancers are often expensive, time-consuming, and involve CT and PET scans and invasive higher frequency technology. “Our biosensor offers a noninvasive and highly efficient solution, leveraging the unique properties of terahertz waves — a type of radiation with lower energy than x-rays, thus safe for humans — to detect subtle changes in cell characteristics.” The sensor features tiny, asymmetric resonators on a flexible substrate and can detect subtle changes in the properties of cells. Unlike traditional methods that rely solely on the refractive index, the device analyzes a combination of parameters, including resonance frequency, transmission magnitude, and a value called “full width at half maximum.” The approach gives a more complete picture of the tissue, allowing for more accurate differentiation between healthy and cancerous cells and to measure the degree of malignancy of the tissue. A demonstration of the flexibility of the biosensor (a). A fabricated metasurface biosensor under an optical microscope (b,c). Cultured 3D collagen gel models of BCC in 24-well plates (d). A close-up view (e). Courtesy of Shohreh Nourinovin et. al./IEEE Transactions on Biomedical Engineering. In tests, the biosensor successfully differentiated between normal skin cells and basal cell carcinoma (BCC) cells, even at different concentrations. The sensitivity of the device holds immense potential for improving patient outcomes by providing early-stage detection. “The implications of this study extend far beyond skin cancer detection,” Nourinovin said. “This technology could be used for early detection of various cancers and other diseases, like Alzheimer's, with potential applications in resource-limited settings due to its portability and affordability.” According to Qammer H. Abbasi, co-director of the University of Glasgow’s Communication Sensing & Imaging Hub, “Integrating terahertz imaging technology into this type of flexible, portable, reusable sensor could make cancer screening a quicker and more comfortable procedure for patients.” The researchers intend to expand on the work through continued collaboration. “We believe this biosensor has the potential to save countless lives by enabling early detection and intervention for various cancers,” said Akram Alomainy, head of the Antennas & Electromagnetics Research Group at Queen Mary University. The research was published in IEEE Transactions on Biomedical Engineering (www.doi.org/10.1109/TBME.2024.3364386).