Methods employing fluorescence quenching by metal surfaces

Abstract

The invention is broadly directed to methods for sensitively detecting proximity changes in systems that utilizes an interacting fluorophore and quencher. In such methods, a metal surface is used as the quencher. The metal surface may be a particle or film, such as nanoparticles or a coating, respectively. Such systems provide an increase in sensitivity over previously-described quenchers, offering a signal-to-noise ratio of up to several orders of magnitude. Examples of such systems in which proximity changes are usefully detected include conformational changes in biomolecules resulting from their interaction with their binding partners or ligands. Such biomolecules may be, for example, nucleic acids, proteins, peptides, polysaccharides, or other polymeric, naturally occurring or synthetic molecules. These include, by way of non-limiting example, molecular beacons, which detect particular polynucleotide sequences; antibody-antigen interactions, and conformational changes in proteins upon binding to a ligand or substrate.

Dependencies are inferred from the claim text.