A High Sensitive Refractive Index-Based Terahertz Biosensor for Virus Detection

Abstract

PurposeTo design and analyze a highly sensitive and stable metamaterial-based Terahertz (THz) biosensor for virus detection.MethodsThe proposed THz biosensor utilizes a flower-shaped resonator design enabling miniaturization and precise control over THz pulse interaction with biological samples. The sensor's design is characterized and its sensitivity is evaluated based on refractive index measurements. The analysis includes assessing the sensor's performance against different viruses including M13 bacteriophage, HSV, Influenza A, and HIV-1. The influence of sample thickness is also examined. The implementation involves determine the peak theoretical sensitivity and estimating the sensor's free space absorptivity.ResultsThe biosensor has a footprint of 0.751 λeff × 0.751 λeff, where λeff represents the wavelength at the operating frequency 8.0299 THz. The sensor demonstrates a peak theoretical sensitivity of 924 GHz/Refractive Index Unit (RIU) with an estimated absorptivity of 99.9% in free space. The sensor's rotational symmetry ensures polarization insensitivity, stability up to 90° of incident angle and insensitivity to incident modes. The performance evaluation against multiple viruses reveals an average sensitivity of 891.917 GHz (RIU) and a high Figure of Merit.ConclusionThe proposed THz biosensor presents a highly sensitive and stable platform for virus detection. The sensor achieves excellent sensitivity and absorptivity enabling accurate identification of viruses. The sensor's compact size and robust performance make it a promising tool for biosensing applications. The results demonstrate its potential for detecting viruses such as M13 bacteriophage, HSV, Influenza A, and HIV-1. The proposed sensor contributes to advancing virus detection methods.