Metamaterial-Based THz Biosensor for Cancer Cell Diagnosis

This paper introduces a biosensor design using metamaterials to detect cancer cells in the terahertz (THz) spectrum. The ability of THz radiation to interact non-invasively with biological elements like cancer cells makes it suitable for in vitro diagnostic applications. Proposed design features a metamaterial unit cell patch consisting of a gold layer on a Teflon (PTFE) substrate. This configuration achieves significant field confinement in the sensing area, leading to heightened absorption, sensitivity, and quality factors across the frequency range from 4.95 THz to 5.25 THz. The variation in the sample refractive index (RI) from 1.35 to 1.40 affects the resonance frequency. As a result, detection of breast cancer cells, cervical cancer cells, Jurkat cells, MCF-7 cells, Hela cells, and PC12 cells is achieved with good sensitivity. A comprehensive analysis is conducted using the Finite Element Method (FEM). A sensitivity of 450 GHz/RIU and full width at half maximum (FWHM) of 0.0427 THz are achieved. So, the figure of merit (FoM) of the sensor is 10.54 and a quality factor of 117.8 are noted for the MCF-7 cancer cell at 5.03 THz.