Surface Plasmon Resonance Sensing: Periodic metallic nanostructures for high-sensitivity biosensing applications

Surface plasmon resonance (SPR) sensing is a real-time and label-free detection technique. To obtain the best biosensing performance, sensors with high surface sensitivities and small resonance linewidth are required. We propose using the hot-embossing nanoimprint lithography method to make high-quality metallic nanostructures and Fano coupling mode in capped nanoslit arrays for generating ultrasmall resonance linewidth. Using the capped nanoslit arrays with multiple periods, the sensing chip can be used for qualitative and quantitative analyses of antigen?antibody interactions. The protein layer attached on the chip can be directly observed, and the concentration levels of the analyte can be estimated with the naked eye. Such nanoplasmonic biochips can benefit sensing applications on point-of-care diagnostics.