High Sensitivity Sensor Based on Bound State in the Continuum in Detection for Cancer Cells

Although terahertz (THz) metasurfaces based on bound state in the continuum (BIC) have garnered significant attention in biomedical applications, their technical implementation in high-sensitivity cancer cells detection remains a critical challenge. In this work, we present a THz biosensor employing dual split-ring resonator (DSRR) arrays based on quasi-bound state in the continuum (Q-BIC). Numerical simulations reveal a high-Q resonance dip at 2.35 THz with a detection sensitivity of 522 GHz/RIU. Experimentally, the performance was validated by detecting normal cells (murine splenocytes) and three cancer cell lines (LLC, LoVo, and MC38). In addition, analysis of cell type discrimination was achieved by integrating machine learning algorithms to project high-dimensional spectral data into a low-dimensional space. This study establishes a label-free approach for long-term cellular monitoring, advancing THz technology as an innovative platform for practical biomedical applications.