Biosensor Based on Photonic Crystal Fiber for Surface Plasmon Resonance Detection

This study introduces a biosensor based on a surface plasmon resonance (SPR) photonic crystal fiber (PCF) for sensitive detection. The design can confine light in a single mode within the core by a lattice of air holes, the fiber is coated by circular gold film. The performance of the sensor was rigorously evaluated through numerical simulations using the full-vector finite element method (FVFEM). The proposed design was improved by systematically optimizing measurements such as air hole diameter (d), lattice pitch (Λ), and gold layer thickness (tg) to maximize sensitivity. The optimized device demonstrated outstanding wavelength sensitivity across a spectrum of biological analytes: 7,333 nm/RIU for HeLa (cervical cancer), 5,500 nm/RIU for Jurka (T lymphocyte cancer), 5,000 nm/RIU for PC12 (adrenal tumor), 6,250 nm/RIU for the HIV virus, 8,571 nm/RIU for MDA-MB-231 (breast cancer), 7,692 nm/RIU for MCF-7 (breast cancer), 3,857 nm/RIU (HIV infection ) and 4,000 nm/RIU for Glucose solution. Consequently, this PCF-SPR presents a promising and cost-efficient alternative to conventional diagnostic techniques such as surgical biopsy, medical imaging, and chemical assays, with the potential to enable easier and earlier disease detection.