Patent ID: 7485453

Claim:
A method for producing biosensors, comprising: forming a blocking layer of thiol-containing molecules on a metalized substrate member, the thiol-containing molecules forming thiol-metal bonds with the metal surface of the substrate member; exposing the substrate member to an oxidizing enhancing stimulus through a mask having a pattern of exposed areas and protected areas, said exposure being of sufficient time to oxidize the thiol-metal bonds in the exposed areas of the blocking layer under the mask; exposing the substrate member to a first source of thiolated biomolecules without an intervening washing step, for a time sufficient to remove the oxidized thiol-metal bonds in the exposed areas and form a layer of the first thiolated biomolecules directly on the metalized substrate member at the oxidized areas of the blocking layer by displacing the oxidized thiol-containing molecules in the exposed areas with the first thiolated biomolecule, the first thiolated biomolecules being specific for an analyte of interest having a particular size, the first thiolated biomolecules defining active areas of receptive material in a pattern corresponding to the oxidized areas defined by the exposing to oxidize step, wherein when the biosensor is exposed to a medium containing the analyte of interest, the analyte binds to the receptive material in the active areas such that the particular size of the analyte of interest, with or without a diffraction enhancing element, facilitates subsequent diffraction of light in a diffraction pattern corresponding to the active areas.