Directional Fluorescence Based On Surface Plasmon-Coupling

Fluorescence technology, including the optical sensing and microscopic imaging, has been playing important roles in biology research and medical diagnosis. However it still remains a great challenge to meet the increasing needs of sensitivity and applicability. Surface plasmon-coupled emission (SPCE) is a novel technique that can significantly improve the ability of fluorescence technology. In SPCE, the excited fluorophores will couple with surface plasmons on a continuous thin metal film, which in turn radiate into the higher refractive index media with a narrow angular distribution. Attributed to the direction emission, the sensitivity can be highly improved with the high collection efficiency. This review will summarize the unique features of SPCE that are important in analytical researches, in particular, with a focus on the recent advancements in the strategies for improving the SPCE performance. The optical imaging based on SPCE and some examples of the analytical applications of SPCE are also highlighted. Recent achievements in SPCE suggest that it could provide new technical platforms with widespread potential applications in various areas, such as nucleic acid, protein and other biochemical sensing.