SPR biosensor based on carbon nanomaterials for carcinoma sensing

This study presents a numerically optimized surface plasmon resonance biosensor based on a CsF/Ag/TiO 2 /graphene oxide multilayer for low-level carcinoma sensing. The optical response was analyzed at 633 nm using the transfer matrix method under angular interrogation. Prism material, Ag thickness, TiO 2 thickness, and carbon nanomaterial overlayers were systematically evaluated to identify the most effective sensing configuration. The selected CsF/Ag/TiO 2 /GO structure exhibited strong concentration-dependent behavior, with the best performance in the low-concentration range. A maximum sensitivity of 415.05 °/RIU was obtained at 1 ng mL -1 , while 402.16 °/RIU was maintained at 2 ng mL -1 , together with favorable resonance quality. Electric-field analysis showed pronounced interfacial confinement and analyte-side penetration, supporting the observed refractive-index response. Comparative assessment against reported SPR biosensors indicates that the proposed architecture is a competitive platform for label-free and early carcinoma detection.