Highly Sensitive Plasmonic Biomedical Sensor for Total Solids in Human Urine Monitoring
摘要
In this research, we suggest a real-time biomedical sensor for monitoring of total solids in human urine with high sensitivity based on a surface plasmon-polariton structure. The design consists of a concentric square and disk nano-resonator that are coupled with air waveguide both etched on a metal layer. The square and disk resonators are infiltrated with biomedical urine samples. The refractive index of human urine varies as the concentration of total solid changes. The obtained resonance peaks are delicate to the refractive index of the urine samples that are infiltrated within the nano-resonators. Therefore, the proposed design can be used to detect the concentration of total solids in urine samples. An efficient finite difference time domain (FDTD) method has been utilized to investigate and analyze the proposed design through optical transmittance. Further, the impacting parameters regarding the effectiveness of the suggested biomedical sensor have been investigated. The suggested sensor has a maximum sensitivity that reaches 1960.71 nm/RIU. Besides, a quality factor of 13.72, the figure of merit (FOM) of 10.07 RIU−1, and ultra-high linearity of 0.9999 can be achieved. Based on simplicity and the high sensitivity of the reported design, the suggested biomedical sensor gives a promising usage in measuring the total solid concentrations in the urine, it can be fabricated with cutting-edge technology, and it is a good candidate for healthcare capabilities.