Design and analysis of a photonic crystal-based biosensor for the detection of chikungunya virus

Abstract

A two-dimensional photonic crystal biosensor is theoretically demonstrated and investigated based on refractive index sensing. It detects the chikungunya virus (CHIKV) in the various blood components with high sensitivity of 421.5 nm/RIU. Simulation and various analyses are done with both normal and infected blood constituents (uric acid, platelets and plasma) to detect CHIKV. The sensor operates within the wavelength range of 1230–1560 nm. The important optical parameters such as sensitivity and quality factor are analyzed and numerical investigations are done with the finite difference time domain method. The sensor is built with a circular array of holes etched on a silicon slab in a hexagonal lattice pattern. A nanohole resonant sensing cavity is placed at the center of two waveguides, enhancing the light–matter interaction of the analyte and trapping the optical mode at the nanohole of the sensor. When the sensor is completely submerged in blood constituents infected with CHIKV (plasma, platelets and uric acid), the resonating modes undergo a shift as the refractive index of each analyte is unique. The sensor has a very high sensitivity of 421.5 nm RIU−1, and a good quality factor of 229.68 for the different blood constituents is obtained. A maximum transmission of 89.25% with a detection limit of 0.01 are obtained and reported in this work.