Periodic nanohole arrays with shape-enhanced plasmon resonance as real-time biosensors

The authors report a combination of the enhanced transmission effect and shape resonances in a periodic array of nanoscale double-hole structures in a gold film to enhance the detection sensitivity of surface plasmon biosensors. Finite-difference time-domain calculations are used to quantify field enhancement at the apexes of the double-hole structure. The double-hole array was used to measure the formation of a self-assembled monolayer and for real-time sensing of protein adsorption onto a gold surface. This result demonstrates the potential to integrate propagating surface plasmons and localized shape resonances to improve real-time biosensors.