Polarization-Insensitive Nano-Metamaterial Sensor with Near-Infrared $\mu$ and $\epsilon$ Negative Properties for Early Cancer Detection via Exosome Analysis (70 THz to 3 PHz)

Metamaterials (MTMs) have emerged as essential components in high-performance electromagnetic devices, including sensors and absorbers. This study presents a polarization-insensitive nano-metamaterial sensor with exceptional angular stability and a wide operating range of 70 THz to 3 PHz. The sensor achieves an average absorption rate of 97% across this range, making it highly suitable for applications in biomedical engineering. By integrating microwave imaging (MWI) techniques, the sensor can detect circulating cancer exosomes (CCEs) with high sensitivity, effectively distinguishing them from normal exosomes. Exhibiting double-negative MTM properties (negative permittivity and permeability) in the near-infrared (NIR) range (70 THz to 400 THz), the sensor enhances sensitivity for early cancer detection. A detailed analysis of its properties, including impedance (Z), phase, and S₁₁ parameters (real and imaginary components), demonstrates its superior performance. This non-invasive, label-free approach to detecting cancer biomarkers represents a significant step forward in advancing personalized healthcare.