Abstract: The binding site on an immunoglobulin for a protein is blocked by hydrophobically coupling the immunoglobulin to a blocking agent such as a label. This results in a detection reagent useful in a variety of test assays in which a protein and an immunoglobulin are advantageously used together, but separately. The reagent is useful in the simultaneous determination of IgG and one of IgA or IgM. Anti-IgA-IgG or anti-IgM-IgG is coupled to a hydrophobic label, particularly a pigment or dye, which label blocks the binding site on IgG for Protein A, and labeled Protein A is added.

Abstract: A delivering member for filtering and delivering a sample to a test assay surface includes a prefilter having a sample receiving surface and a surface for delivering a sample to a test assay surface. The prefilter includes a diffusing material on its receiving surface for rapidly and evenly diffusing a sample across the prefilter receiving surface. In this way, a sample may be rapidly and evenly delivered to a test assay surface. A test assay solid phase has a surface including an area carrying an immobilized species and an area free of immobilized species. When a sample is applied to the surface, followed by application of a labeled species, the evenness of distribution of the labeled species is indicative of the evenness of application of the sample. A kit includes a delivering member and an assay surface.

Abstract: Gas containing granules of a resiliently compressible material having a density variable with pressure are used as a solid phase support in liquid phase reactions such in immunological reactions. Varying pressure causes the density of the granules to change and is used for mixing and separating the granules in liquid phase. In an immunological reaction, the granules having an attached antibody are combined with a solution containing an antigen, then varying pressure is applied to the solution to mix the granules in the solution to fix the antigen to the antibody and then pressure on the solution is varied to force the granules to the top or bottom of the solution whereby the solution can be separated from the granules.

Abstract: A quick and simple immunoassay technique applicable to the determination of large molecules like proteins, polynucleotides and others involves labelling competitive immunospecies with an enzyme as signal generator. This enzyme can be converted to the corresponding apo-enzyme form and its regeneration, upon addition of a suitable co-factor, is inhibited by complexation when the labelled specie is reacted with its immunopartner. The degree of complexation is therefore ascertained by measuring the extent of regenerated activity.

Abstract: A mould for the casting of thin, cross-linked, polymerized resin films is subjected, when being filled with the liquid to be polymerized, to a centrifugal force field exceeding that of the earth gravitation field, the whole being for equalizing the intimate structure of the polymer and to expel therefrom the bubbles of gas possibly present therein. After curing the gel, a mixture of compounds to be separated by the application of an electric field is introduced into the gel and the latter is subjected to electrophoresis within the mould itself.