Bio-sensing applications of a 2:1 photonic crystal multiplexer

In this work, a two-dimensional ring-shaped photonic crystal structure is proposed. The proposed structure is consisted of 28*25 silicon rods situated in air medium. Fundamental properties of the proposed structure (acting as a biosensor) are investigated through photonic bandgap (PBG) and field distribution diagrams. The proposed structure is considered for diagnosis of cholesterol and creatinine levels in blood samples. Proposed structure is designed to operate as a 2:1 multiplexer (also functioning as a biosensor). Thus, by inserting incident signals with specific wavelengths (placed in TE PBG region) to input0, input1 and select ports, light wave can be transmitted to output port. Cholesterol concentrations in blood sample can be detected by considering input0 (I₀ = 1), input1 (I₁ = 0) and select (S = 0). For cholesterol following bio sensing factors will be calculated. Q: (45.4-52.88), S: 2673.4 nm/RIU, DL: (0.00125-0.00143) RIU, FOM: (80.91-82.06) RIU^-1. Creatinine levels in blood samples can also be diagnosed by considering input0 (I₀ = 0), input1 (I₁ = 1) and select (S = 1). For creatinine, Q: (101.1-109.4), S: 3582.7 nm/RIU, DL: (4.98e-4-5.26e-4) RIU and FOM: (199.01-201.3) RIU^-1 will be calculated. Finally, proposed system can effectively help physician in early and precise prognosis of hypercholesterolemia and acute kidney injuries.