A Biosensor for the Detection of Anemia Using Metal Ag and Defect Multilayer Photonic Crystal

Hemoglobin in a blood sample has been analyzed for the diagnosis of anemia cancer in a human’s body by using metal/defect/metal multilayer one-dimensional (1D) photonic crystals. The proposed structure contains five periodic layers of Si/BaF 2 and a very thin defect layer of blood sample between two thin metal layers of Ag. In this case, a low concentration of hemoglobin in red blood cells (RBC) which is a function of refractive index indicates anemia cancer in the patient. The modification of the refractive index or concentration simply causes a shift in the transmittance of the defect mode in the photonic bandgap, which can be used for anemia diagnosis. To analyze the transmittance properties, the thickness of a metal layer, angle of incidence, and refractive index/concentration of the defect layer have been varied by using the transfer matrix method. It is analyzed that the shifting of the transmission peak has been improved further with an increase in metal layer thickness and incident angle. Detailed analysis shows that the proposed device contains a quality factor of 990 and a sensitivity of 892.85 nm/RIU. Detailed analysis shows that the proposed device demonstrates very high sensitivity when the defective layer is placed between two metal layers. So the proposed device may have potential applications in biosensing.