Surface Plasmon Resonance (SPR) Sensing Based on DNA Elongation by Site-Selective Surface Plasmon (SP) Field Heating toward Ultra-High Sensitive Detection of Single Pathogenic Particles

Abstract

In this study, site-selective enzymatic DNA elongation from gold surface at 25°C was induced by the damping heat of propagating surface plasmon (SP), using an 808 nm laser. A multispot immunoassay, based on this concept, has been demonstrated. The primer-immobilized analyte-bound ligand spot was selectively heated by the SP field, and effective DNA elongation on the surface using rolling circle amplification produced an intense fluorescence spot on the surface after staining. The key feature of this method is the temperature contrast on the surface. We have estimated the surface temperature by comparison of the yield and chain length of the amplicons from SP heating to those from controlled thermal reactions at a series of temperatures.