Detection method based on a surface plasmon resonance and its application to flow injection analysis and liquid chromatography

A simple surface plasmon resonance (SPR) experimental set-up has been made for investigating further applications of the SPR detection method in analytical chemistry. In the home-made SPR experimental set-up, a Ag film with a thickness about 50 nm was deposited on the flat surface of a hemicyclindrical prism, and a flow cell was attached directly to the flat surface of the prism. It has been confirmed that SPR occurred in the experimental setup using model samples of water and alcohols. The SPR detection modes, based on changes in the coupling angle and reflectivity at a fixed angle, were investigated both theoretically and experimentally. It has been shown that the SPR detection mode based on the reflectivity change is much more sensitive than that based on a change in the coupling angle, for the SPR experimental set-up. A preliminary investigation indicates that the SPR method can be used as a universal detector for HPLC or FIA or other analytical methods. Its problems, improvements, and future applications in analytical chemistry are also discussed.