FIBER-OPTIC ASSAY APPARATUS BASED ON PHASE-SHIFT INTERFEROMETRY
摘要
Apparatus and method for detecting the presence or amount or rate of binding of an analyte (46) in a sample solution is disclosed. The apparatus includes an optical assembly (26) having first (42) and second (40) reflecting surfaces separated by a distance "d" greater than 50 nm, where the first surface is formed by a layer of analyte-binding molecules (44), and a light source (22) for directing a beam of light onto said first and second reflecting surface. A detector (28) in the apparatus operates to detect a change in the thickness of the first reflecting layer resulting from binding of analyte to the analyte-binding molecules, when the assembly is placed in the solution of analyte, by detecting a shift in phase of light waves reflected from the first and second surfaces.