Hypercholesterolemia and Hyperglycemia Diagnosis by Photonic Crystal Biosensor

In the proposed work, a 2-D photonic crystal-based biosensor is designed, and its applications are investigated. Designed system is consisted of 25*21 silicon rods which are positioned in air medium. Basic characteristics of proposed system (operating as biosensor) are investigated through obtaining photonic bandgap (PBG) and electric field spectra. In order to utilize designed system as a biosensor, incident fields with specific wavelengths (in TE PBG region) would be applied to input port. Incident signal will circulate in system reaching outputs 1 or 2 for detection of glucose and cholesterol. Light waves at λ = 1740 nm would be mainly transferred to output1 for diagnosis of glucose concentrations. Remarkable biosensing factors of quality factor (Q): (165.7–171.71), sensitivity (S): 1607 nm/RIU, detection limit (DL): (6.53e-4 − 6.92e-4) RIU and figure of merit (FOM): (159.03–172.8) RIU^− 1 would be achieved. Signals with λ = 1250 nm at output2 would be utilized for diagnosis of cholesterol with (Q): (50–62), (S): 1109.3 nm/RIU, (DL): (2.25e-3 − 2.78e-3) RIU and (FOM): (44.37–53.8) RIU^− 1. Referring to obtained results, physicians can effectively and precisely diagnose hypercholesterolemia (causing heart diseases) and hyperglycemia (leading to diabetes) in early stages.