Metasurface immunosensor and the prospects of artificial intelligence applications

This paper proposes and fabricates a terahertz metasurface bioimmunosensor based on an antibody-modified graphene and gold nanoparticle composite for specific recognition of immunoglobulin M (IgM). The metasurface structure was simulated and designed using the finite time-domain difference method, and samples were prepared using micro-nanofabrication techniques. A graphene and gold nanoparticle composite functional layer was constructed on the sensor surface using a silane coupling agent (KH550), and then functionalized with antibodies. The sensor was used to detect the concentrations of IgM, ovalbumen, and whey protein. Experimental results show that the metasurface resonant frequency changes linearly with increasing IgM concentration. When comparing ovalbumen and whey protein at the same concentration, only IgM elicits a significant response, confirming the sensor’s specificity. The designed sensor exhibits a wide detection range and is label-free, demonstrating potential applications in biomarker detection and early disease diagnosis.