An Optical Fiber-based SPR Sensor for Hepatocellular Carcinoma Detection

An optical fiber-based surface plasmon resonance sensor for hepatocellular carcinoma diagnosis is presented here. Conventional, tip-based, and D-shaped configurations are used to construct the sensor. The sensing region length, the bimetallic layer, full width at half maximum (FWHM), figure of merit (FOM), sensitivity, and signal-to-noise ratio (SNR) have been used to analyze the sensor performance. The sensor setup uses three layers: a ZBLAN fluoride optical fiber core (optical substrate), a 40 nm-gold or 40 nm-silver films (plasmonic metal), and healthy and pathological samples (analyte). Moreover, a bimetallic layer has been also investigated, where the thicknesses ranged from 10 nm to 40 nm. Also, the sensing region varied from 5 mm to 60 mm. The results obtained for the sensitivity of the simulated sensors were: 3, 903.4 nm/RIU for gold, 3, 821.5 nm/RIU for silver, and 3, 415.1 nm/RIU for silver-gold layer.