X-shaped exposed core highly sensitive plasmonic sensor for cancer cell detection

For accurate bio-sample identification, we present a unique optimized surface plasmon resonance sensor based on an X-shaped exposed-core photonic crystal fiber. Applications are made easier by the placement of the target analyte and plasmonic material on the fiber’s exterior surface. The sensor has four separate silica channels that reach from the core to the metallic outer surface creating X-shape. These channels were intentionally placed to provide the highest sensitivity while maintaining the sensor’s ability to be manufactured. Within a refractive index range of 1.33 to 1.40, our optimized sensor demonstrates improved detecting abilities, including a wavelength sensitivity of 8000 nm/RIU and amplitude sensitivity of -1175.12 RIU^-1. The suggested sensor also exhibits exceptional performance parameters, such as a resolution of 1.25×10^-5, a maximum signal-to-noise ratio (SNR) of 2.041 dB, a figure of merit (FOM) of 160.0 RIU^-1, a detection accuracy (DA) of 0.02 nm⁻¹, and minimum full width half maxima (FWHM) of 50 nm. When examining variations in the optical properties of the PCF due to different RIs of normal and cancer cells using finite element analysis, we achieve amplitude sensitivities of -844.91, -418 and -1221.8 RIU^-1 for HeLa, Basal and MDA-MB-231 cell lines, respectively.