Urine glucose concentration detection biosensor using one-dimensional photonic crystals with periodical and Fibonacci sequences based on Tamm plasmon resonance

Abstract

This paper presents the design of biosensors utilizing one-dimensional photonic crystals with periodical and Fibonacci sequences for measuring glucose concentration in urine, aimed at facilitating continuous blood glucose monitoring for diabetic patients. Exploiting Tamm plasmon resonance within a photonic band gap in the medium wave infrared band, the biosensor comprises a configuration with a one-dimensional photonic crystal and an Ag layer deposited on an infrared prism, with a urine sample layer in between. Utilizing the transfer matrix method, the reflection spectra for electromagnetic waves are calculated. The wavelength position of the Tamm plasmon resonant dip is influenced by variations in glucose concentration within the urine sample. This is attributed to the distinct refractive indices exhibited by urine samples with different glucose concentrations. Optimizing biosensor performance under various incident angles involves adjusting the Ag layer and urine sample thicknesses while maintaining excellent linear characteristics. The optimal performance of the biosensor with Fibonacci sequence one-dimensional photonic crystal is significantly superior, with a sensitivity of 113,000 nm RIU−1, a figure of merit of 2.05 × 105 RIU−1, and a detection limit of 4.84 × 10−7 RIU. The combination of high performance and a straightforward structure makes the proposed biosensors for detecting urine glucose concentrations promising in biomedical diagnostics.