Abstract: The present invention relates to a diagnostic assay device comprising a fluorophore element comprising a fluorophore imbedded therein, and a reagent element. The fluorophore element and reagent element have opposed surfaces which are spaced apart throughout a liquid transport zone a distance effective to cause capillary flow of a sample liquid introduced therebetween throughout the liquid transport zone, the opposed surface of the fluorophore element carrying a plurality of projections arranged throughout the surface in the liquid transport zone, each projection being spaced apart from the others in a predetermined pattern and being in contact or virtual contact with the opposed surface of the reagent element.

Abstract: There is described an assay system for the assessment of unoccupied specific ligand binding sites on proteins in biological fluids. The assay is carried out with a multilayer assay element and is based on the principle of equilibrium distribution in which a ligand distributes itself between unoccupied sites on the proteins and the remainder of the element. The ligand can be labeled with a detectable moiety or it may be unlabeled and detected through the use of another detectable species. In one embodiment the assay format is utilized to estimate the number of sites on thyroxine binding globulin (TBG) which are not occupied by thyroxine (T4) or triiodothyronine (T3).

Abstract: A method for determining the amount of an analyte in a sample fluid utilizing an assay element which comprises at least one reagent layer. The assay method includes the steps of optically reading a signal producing species, e.g., a fluorescent label, a first time prior to depositing the sample fluid on the assay element and a second time, at the same wavelength and in the same location within the assay element after the sample fluid has been applied to the assay element and the sample analyte has interacted with the reagent(s) present in the assay element. The first, or dry, reading is corrected for relative humidity and/or temperature variations.

Abstract: A method for determining the amount of an analyte in a sample fluid utilizes a multilayer assay element which comprises at least one reagent layer and a light-blocking layer. The assay method includes the steps of optically reading a signal producing species, e.g. a fluorescent label, a first time before the sample fluid is applied to the assay element and a second time, at the same wavelength and in the same location within the assay element, after the sample fluid has been applied to the assay element and the sample analyte has interacted with the reagent(s) present in the assay element. The ratio of the two signals is taken and compared with that for known amounts of the analyte to determine the amount of analyte in the sample fluid.

Abstract: There is provided a biological diagnostic assay system wherein a phenoxy-substituted naphthalene compound, such as phenoxynaphthalene sulfonate, or a salt thereof, is utilized to prevent plasma proteins such as serum albumin from binding to other components of the assay and/or to displace plasma proteins which have become bound to other components of the assay.

Abstract: A liquid transport system provides controlled flow of liquid in a liquid flow zone between two surfaces wherein one surface includes a plurality of projections, or raised areas, arranged substantially throughout the surface in the liquid flow zone and an aperture for allowing the introduction of liquid between the two surfaces. In a preferred embodiment the projections on the first surface are arranged in parallel spaced rows and parallel spaced columns. The second surface may be one surface of a layer of a diagnostic assay element.

Abstract: Fluorescent compounds which are conjugates of a biologically active moiety and an arylidene dye moiety. The compounds have a large Stokes shift and are useful in applications such as biological diagnostic elements.

Abstract: The blue light response of solid state photosensitive devices such as silicon based charge-coupled devices (CCDs), charged-injection devices, photovoltaic devices and the like is enhanced by applying to the surface thereof a thin layer which includes a first, or donor, dye which absorbs efficiently in the blue region of the spectrum and a second, or acceptor, dye which absorbs efficiently in the green region of the spectrum, there being substantial overlap between the emission spectrum of the donor and the absorption spectrum of the acceptor. The relative concentrations of the dyes are controlled such that the donor dye transfers energy nonradiatively to the acceptor dye which is caused to fluoresce thereby emitting light in the region where the device has substantial photoresponse.