Design and Numerical Analysis of a PCF-SPR Sensor for Early-stage Malaria Detection

This paper presents a photonic crystal fiber (PCF)-based surface plasmon resonance (SPR) sensor designed to achieve precise malaria detection in blood samples. The sensor's innovative architecture incorporates carefully optimized layers of plasmonic materials, including gold and TiO2, to attain sensitivity and specificity. Extensive assessment of this sensor's performance has been carried out through rigorous finite element analysis using COMSOL Multiphysics v5.6. The sensor's configuration features a gold-coated PCF with a thin analyte layer, enabling the external detection of malaria parasites within blood samples. The air-hole configuration of the PCF sensor resembles the shape of a "barred spiral galaxy". It has undergone comprehensive testing across various stages of infected blood cells (ring, trophozoite, schizont), as well as normal red blood cells, each with their distinct refractive indices (RI). Through meticulous adjustments to the sensor's geometric parameters, remarkable wavelength sensitivity of 17,857.14 nm/RIU and amplitude sensitivity of 442.92 RIU-1 have been achieved for the ring phase, 10,210.53 nm/RIU and 392.72 RIU-1 for the trophozoite phase, and 8758.62 nm/RIU and 352.86 RIU-1 for the schizont phase. The numerical investigation also shows that the sensor possesses a low confinement loss of 50.25 dB/cm, 34.97 dB/cm, 28.74 dB/cm, and 25.47 dB/cm for normal RBC, ring phase RBC, trophozoite phase RBC, and schizont phase RBC, respectively. The results confirm the potential of the proposed sensor to detect malaria compared to existing methods. Hence, this sensor holds significant promise for advancing malaria detection and monitoring in blood samples, potentially leading to improved diagnostic and management strategies for this disease.