DESIGN AND SIMULATION OF SPR BASED PCF SENSORS FOR PRELIMINARY MALARIA DETECTON AND RI SENSING

Abstract

This research presents the design and numerical simulation of two ultra-sensitive surface plasmon resonance (SPR) sensors based on photonic crystal fiber (PCF) for early disease diagnosis and high-performance refractive index (RI) sensing. The first design suggests a double-side polished twin-core PCF SPR sensor optimized for the detection of malaria at early stages. By employing a gold-coated hourglass-shaped configuration, the sensor achieves significant core mode-surface plasmon mode coupling, resulting in high wavelength sensitivities of 26,428.57 nm/RIU, 16,052.6 nm/RIU, and 12,586.2 nm/RIU for ring, trophozoite, and schizont stages of infected red blood cells, respectively. High figures of merit (FOM) values also attest its application in biomedical diagnostics. The second sensor design examines a side-polished PCF structure coated with a bilayer of 40 nm gold and 12 nm TiO₂, leveraging the plasmonic enhancement properties of the 2D material TiO₂. The structure boasts an impressive improvement in sensitivity, with peak wavelength sensitivity ranging from 4000 nm/RIU for the plain gold sensor to 27,000 nm/RIU for the TiO₂–gold coated structure. These two sensors together demonstrate the ability of SPR-PCF platforms to facilitate highly sensitive, miniaturized, and selective detection devices beneficial in applications for malaria diagnostics, RI sensing, and other biomedical and environmental monitoring aims