Optimization of surface plasmon resonance-based biosensors for monitoring hemoglobin levels in human blood

Abstract

Biological sensors based on surface plasmon resonance (SPR) are used in a wide range of fields such as pharmacy, medicine, food and drink safety to measure biological and chemical parameters. These sensors function by detecting changes in the refractive index of the sample environment. In this paper a biosensor design based on surface Plasmon resonance is introduced for the purpose of monitoring hemoglobin concentrations in human blood. Our design is based on a Kretschmann structure which contains an SF10 prism, with metal, graphene and metal dichalcogenide layers. The optical source considered here is a He–Ne laser with the wavelength of 632.8 nm. The effect of adding graphene and metal dichalcogenide layers to the structure of these sensors has been investigated. Our investigation of this structure shows that depending on the specific structure of metal dichalcogenide, the addition of this layer increases the sensitivity of the sensor. Using this optimized structure, our main goal of a blood health monitoring device can be achieved. We use this structure to determine the reflection coefficients that correspond with the healthy range of hemoglobin concentration in human blood based on the refractive index of human blood. This sensor is first optimized for sensitivity using water as a sample, this optimized sensor is then used to investigate the range of human blood in a healthy state of blood iron for men and women between the ages of 20 until 80 years. Results show that the reflection coefficients of the optimized structure for healthy range of hemoglobin concentrations for an adult man is from 0.6805(a.u) to 0.7067(a.u) and for an adult female is from 0.6547(a.u) to 0.6583(a.u).