Patent ID: 7205155

Claim:
A method of assaying substances comprising the steps: providing a surface that has a top and a bottom and at least one reaction partner R 1 bonded to the top of said surface; placing in contact with said surface a solution that contains at least the substance being assayed, at least one compound containing a fluorophor and at least one dye that absorbs in the absorption and/or emission range of the fluorophor, wherein a complex forms on reaction partner R 1 on said surface and wherein said complex is formed by covalent or non-covalent interactions of reaction partner R 1 with the substance being assayed and by covalent or non-covalent interactions of the at least one compound containing a fluorophor with the substance being assayed; projecting a beam of light onto the bottom of the surface, said beam of light being totally reflected on the surface of the phase boundary, thereby forming an evanescence field over said surface, wherein said dye is present in the solution at a concentration sufficient to absorb 70% or more of the light entering the solution within 1 mm above the top of said surface; and exciting the fluorophor bonded to said surface by said evanescence field and measuring the fluorescence produced as a measure of the substance being assayed.