A Waveguide-Coupled Surface Plasmon Resonance Sensor Using an Au-MgF2-Au Structure

We describe an Au-MgF 2 -Au trilayered waveguide-coupled surface plasmon resonance (WCSPR) sensor in this article. The characteristics of this sensing structure are compared with those of the conventional single-layered gold surface plasmon resonance (SPR) sensor theoretically and experimentally. The experiment results show that WCSPR can provide not only seven times smaller refractive index resolution in the bulk sensing application but also more accurate measurement results for the biomolecular interaction analysis than the conventional single-layered gold SPR. What’s more, this high-resolution sensor is easy to build and not sensitive to film thickness variations. The Au-MgF 2 -Au trilayered WCSPR may provide a simple and convenient chip-based strategy for performance enhancement of SPR sensors without varying the hardware and software of measurement instruments.