Reusable meta surface biosensors based on Fano resonance with microfluidic technology

Gold metarsurfaces are widely used in sensing due to their ability to enhance localized light fields. To reduce the manufacturing cost of gold metasurfaces, we proposed a reusable metasurface biosensor based on parylene C with microfluidic technology. The electric field distribution of the gold metasurface was simulated using the finite-difference time-domain (FDTD) method. The polydimethylsiloxane (PDMS) microfluidic channels were bounded on the surface of the biosensor to provide specific reaction area to detect different concentrations of NaCl solution. For the purpose of reusability, the growth and removal of parylene C on the metasurface were realized. Besides, the parylene C film acted as the connection layer to enable the one-step physical modification of antigen and antibody, which made highly efficient biosensing possible. The feasibility of this approach is experimentally validated and has potential to be widely used in other metasurface biosensors.