Gradient boosting-assisted polarization-independent SPR biosensor for multiplexed diagnostics and behavioural prediction

Abstract

This work presents a graphene-based metamaterial terahertz (THz) sensor designed for the simultaneous detection of glucose and hemoglobin, two crucial biomarkers for diabetes and anemia monitoring. Meanwhile, the proposed sensor integrates a graphene-coated square resonator with copper-coated circular elements and bismuth-coated peripheral squares atop a SiO₂ substrate. Finite element method simulation demonstrates the dual-resonance absorption characteristics corresponding to the distinct molecular signatures of glucose and hemoglobin. Interestingly, this sensor achieves high sensitivities of 1000 GHz/RIU for glucose and 433 GHz/RIU for hemoglobin, with figures of merit up to 23.81 RIU −1 and a high-quality factor of 22.7. Moreover, the parametric studies show tunability via graphene chemical potential and incident angle as well. Additionally, a gradient boosting regressor model predicts sensor response with 93 % accuracy, demonstrating its reliability for real-time biosensing. The proposed dual-analyte platform offers a non-invasive, label-free, and compact diagnostic solution suitable for point-of-care applications in healthcare.