Ultra-sensitive graphene micro-ribbon integrated THz biosensor for breast cancer cell detection

In recent decades, the rising incidence of cancer has made early and rapid diagnosis, along with precise characterization of cancer cells, more crucial than ever. The paper presents a novel metasurface-assisted biosensor operating in the THz regime, designed for non-invasive and rapid detection of breast cancer cells. The proposed biosensor incorporates graphene micro-ribbons to enhance THz wave interaction, boosting the biosensor's sensitivity and overall performance. When used for cancer cell sensing, the biosensor demonstrates three absorption peaks at 2.0012 THz, 2.8734 THz, and 3.2948 THz with the absorption of 99.18 %, 89.55 %, and 99.93 %, respectively. The biosensor achieves a maximum frequency shift of 49 GHz, a maximum theoretical sensitivity of 3.5 THz/RIU (Refractive Index Unit), and a figure of merit of 6.81 RIU^-1. Additionally, the sensor offers an excellent detection limit of 0.26 RIU and a resolution of 0.91 THz. The ability of the proposed biosensor to detect small refractive index changes (as low as 0.26 RIU) adds to the sensor's versatility, allowing it to be used in a wide variety of clinical and laboratory settings. Given these features and performance, the proposed biosensor holds great promise for non-invasive cancer diagnostics, offering ultra-high sensitivity in a portable and miniaturized platform.