Enhanced Surface Plasmon Resonance Biosensor Using Silver, Perovskite Oxides, and MXene Nanostructures for Sensitive Blood Cancer Detection

Recent scientific and technological breakthroughs have led to the development of highly sensitive biosensing technologies for pathogen identification. Surface plasmon resonance (SPR) has emerged as an environmentally friendly and efficient label-free detection technique in clinical research, particularly for examining biomolecular interactions, including those involving hemoglobin. Hematologic malignancies include several forms of malignancy that mostly impact the blood, bone marrow, and lymphatic system. This research introduces an innovative surface plasmon resonance (SPR) biosensor utilizing silver (Ag), perovskite oxide (PO), and MXene (Ti₃C₂Tₓ) nanostructures for the precise detection of blood cancer via hemoglobin concentration assessment. SPR sensors provide label-free, real-time detection, rendering them suitable for clinical diagnostics, especially in the identification of hematologic malignancies like leukemia, which is marked by changed hemoglobin levels. To improve sensor performance, we methodically examined different perovskite oxide materials (BaTiO₃, SrTiO₃, CaTiO₃, and PbTiO₃) and tuned their thicknesses. Among these materials, PbTiO₃ exhibited exceptional sensitivity (up to 664.28°/RIU at a thickness of 5 nm), although CaTiO₃ displayed the highest quality factor (QF = 110 RIU⁻¹), signifying remarkable resonance sharpness and detection precision. The integration of MXene layers enhanced sensitivity owing to their remarkable optical and electrical characteristics, with a peak sensitivity of around 580°/RIU. Nonetheless, the incorporation of MXene significantly expanded the resonance dip, resulting in a minor decrease in the quality factor. A comprehensive investigation revealed an optimum arrangement (Ag-PbTiO₃-MXene) with layer thicknesses of d ₂  = 4 nm (PbTiO₃) and d ₃  = 1 nm (MXene), achieving an exemplary equilibrium between elevated sensitivity (557.14°/RIU) and substantial QF (96.05 RIU⁻¹). These findings underscore the essential trade-offs between sensitivity augmentation and resonance sharpness, highlighting the necessity of meticulous material selection and thickness optimization. The suggested SPR biosensor design exhibits considerable promise for sophisticated biomedical diagnostics, especially for the early and precise identification of hematological malignancies by accurate hemoglobin concentration assessment.