Abstract: The present invention relates to a method of immobilizing proteins on a polymeric matrix by means of plasma activation and an apparatus and process for the use of such material. The protein mixture is applied to the surface of the polymeric matrix with or without the addition of a crosslinking agent. If is then placed into a plasma generator, wherein the functional groups on both the protein and the matrix molecules are activated to form free radicals. Upon returning from their high energy state, the free radicals form covalent bonds between the proteins and between the protein and the polymeric matrix. Using this method, the proteins are nonspecifically immobilized on the surface of the polymeric matrix. The method can be utilized to immobilize proteins on the surface of polymeric membranes, polymeric beads, polymeric tubes and polymeric plates. The immobilized protein has high biological activity and stability.

Abstract: This invention is directed to a ligand-receptor assay for determining the presence or amount of at least one target ligand, capable of competing with a ligand analogue conjugate for binding sites available on a ligand receptor, said ligand analogue conjugate comprising at least one ligand analogue coupled to a signal development element capable of emitting a detectable signal, in a fluid sample suspected of containing said target ligand, comprising the steps of:a. contacting said fluid sample with ligand analogue conjugate and ligand receptor to form a reaction mixture, the relative amounts of ligand analogue conjugate and ligand receptor being such that in the absence of target ligand, and subsequent to substantially equilibrium binding, substantially all of the ligand analogue conjugate is bound to ligand receptor;b. detecting the unbound ligand analogue conjugate;c. relating the detectable signal to the presence or amount of target ligand in the fluid sample.

Abstract: This invention relates to a flotation immunoassay employing a novel buoyant matrix to which an antigen or antibody is coupled and which separates the bound and free products of the assay by floating to the surface of the reaction liquid. The novel flotation device which makes it possible to detect and to quantitate either antigen or antibody can also be used to fractionate cells and molecules.

Abstract: A new method of coupling proteins and other targeting molecules to lipid vesicles has been developed. A bifunctional agent forms a covalent bond without damaging the lipid structure and permits retention of protein activity.

Abstract: Agglutination assays, particularly latex agglutination assays, for simultaneous testing for a multiplicity of ligands. The reagents for use in the assays comprise two or more insoluble colored substances, each substance being adapted to form a distinctively colored agglutinate in the presence of a specific ligand or specific group of ligands.

Abstract: Agglutination assays, particularly latex agglutination assays, for simultaneous testing for a multiplicity of ligands. The reagents for use in the assays comprise two or more insoluble colored substances, each substance being adapted to form a distinctively colored agglutinate in the presence of a specific ligand or specific group of ligands.

Abstract: Agglutination assays, particularly latex agglutination assays, for simultaneous testing for a multiplicity of ligands. The reagents for use in the assays comprise two or more insoluble colored substances, each substance being adapted to form a distinctively colored agglutinate in the presence of a specific ligand or specific group of ligands.

Abstract: A method of performing a diagnostic immunoassay utilizing colloidal non-metal particles having conjugated thereto a binding component capable of specifically recognizing an analyte to be determined. After reaction of the sample and colloidal non-metal particles, the presence or amount of analyte/colloidal non-metal particle complexes are determined by optical analysis as a measure of the amount of analyte in the sample. The method can be utilized for the specific detection of numerous analytes and is sensitive and has a wide detection range.

Abstract: An immunoassay making use of latex agglutination is practized by providing a colored latex as a latex, subjecting the colored latex to an immune reaction to form agglutinated particles of the colored latex, capturing the particles by means of a thin membrane with capillary-shaped pores formed therethrough, and then measuring the amount of the agglutinated particles thus captured.

Abstract: An assay procedure that is particularly valuable for detecting and/or determining the presence of threshold levels of analyte ligands in biological fluids. In one particularized and specialized aspect the disclosure is directed to procedures for detecting and/or determining threshold levels of hormone metabolites such as pregnanediol-3-glucuronide (P.sub.3 G) and estrone-3-glucuronide (E.sub.1 3G) in human urine. The assay consists of contacting a sample containing the analyte with a known amount of an antibody thereto and with a calibrated amount of the analyte itself that is conjugated to said solid support. When the level of the analyte in the sample exceeds a threshold level, such as 5 ug/ml for P.sub.3 G, the antibody will be insufficient to block all of the corresponding analyte on the solid support.

Abstract: A method and apparatus for conducting specific binding pair assays, such as immunoassays, is described. A porous membrane capable of non-bibulous lateral flow is used as assay substrate; a member of the binding pair is affixed in an indicator zone defined in the substrate. The sample is applied at a position distant from the indicator zone and permitted to flow laterally through the zone; any analyte in the sample is complexed by the affixed specific binding member, and detected. A novel method of detection employs entrapment of observable particle in the complex. Blood is a particularly preferred sample as the red blood cells can be used as the observable particles for detection of the complex.

Abstract: A method of determining the presence and quantity of an analyte of interest in a particulate-containing sample is disclosed, as is a construct for use in the method. The method is particularly useful for determining an analyte in whole blood and in fermentation suspensions. The construct is comprised of a first moiety, which is a particulate-binding moiety and a second moiety, which binds the analyte of interest.

Abstract: For the determination of a reaction partner of an immunological reaction according to the principle of immunoassay, the reaction partner to be determined is brought into contact with a marked specific receptor R.sub.1 and at least 1 unmarked receptor R.sub.2, one of the unmarked receptors R.sub.2 being bonded on a solid phase by a binding-capable substance R.sub.3. In order to determine the sample blank value, the unmarked receptor R.sub.2, which is bonded by the receptor fixed on the solid phase, is then replaced by another unmarked receptor R'.sub.2 which does not react with the reaction partner of R.sub.2 to be determined.

Abstract: A process for quantification of cell populations or subpopulations, by incubating a sample with labelled antibodies directed against characteristic surface antigens of the cell population to be quantified to form labelled antibody/antigen complexes. Standards with known, differing particle concentration and having comparable sedimentation behavior to the cells to be determined and further, carrying molecules which are directed against the labelled antibody or a part hereof are also incubated with the labelled antibodies. The cells of the sample solution, as well as the particles of the standard solution, are separated off from the excess labelled antibodies and the amount of the labelling is measured not only on the cells but also on the particles. By comparison of the measurement value from the sample with the measurement values from the standard solutions, there is ascertained the number of cells to be determined in the sample.

Abstract: Materials can be screened for carcinogenic properties by administering them to test animals and assaying biological tissue, preferably plasma, for the presence of a 60K cancer-associated phosphoprotein. The test is applicable to a wide range of chemically-diverse carcinogens and is not restricted to carcinogens having one particular mode of action.

Abstract: An immunoassay process for quantitative analysis of an analyte antigen (or analyte antibody) in an aqueous liquid sample. In the first step, the analyte antigen (or analyte antibody) is allowed to react with an antibody (or antigen) in competition with a known quantity of a labelled antigen (or labelled antibody), the antibody (or antigen) being carried by water-insoluble microparticles in the immobilized state. In the second step, the reaction mixture is spotted on a top porous layer of an integral multi-layered analysis element which includes the top porous layer, an intermediate detection layer and a bottom water-impermeable and transparent support. The top porous layer permeates aqueous solution and has pores sufficiently small to trap all of the microparticles carrying the antibodies (or antigens) bound to the analyte antigen (or analyte antibody) and bound to the labelled antigen (or labelled antibody).

Abstract: Antibody coated gold sol particles and antibody coated solid phase particles dispersed in an aqueous system react immunologically as a function of the presence of an analyte in a sample to be analyzed to produce a collectible, solid phase, gold-containing composite. The composite is collected on a filter or at the bottom of a test tube by centrifugation or gravitation and the analyte in the sample is determined or detected by direct visual examination of the collected solid phase composite which has a pink or red or purplish coloration as a result of the gold contained thereby. The materials required for conducting the assay comprise coated gold particles, coated solid phase particles and a collector element such as a filter. The collected, solid phase, metal-containing composite, which may be directly visually examined to determine or detect the gold therein and thus the analyte in the sample, is stable and remains available for confirmation of test results at a later time.

Abstract: This invention provides a means for determining the concentration of any of a wide range of antibody or antigen molecules with a high degree of specificity, accuracy and sensitivity. Antigen or antibody concentration is determined by effecting an agglutination reaction in a liquid medium and determining the cluster size distribution of agglutinated particles by optical pulse particle size analysis. The measured cluster size distribution then is compared with a standard quantitative relationship between the cluster size distribution and concentration of the antigen or antibody being tested. By this means one may specifically ascertain the absolute concentration of the antigen or antibody in question in the sample being analyzed. In addition to detecting antigen or antibody molecules, the process of this invention can be used to determine the concentration of any substance capable of specifically promoting or inhibiting an agglutination reaction such as viruses, white blood cells or the like.

Abstract: A device is provided for determining the presence of an antigen which comprises a trapping zone, which contains material capable of capturing free flowing enzyme linked antibodies, but not antibodies bound to a transport particle which flows freely through the trapping zone into the substrate zone, and a substrate zone which contains material capable of reacting with enzyme-linked antibodies to produce a reaction which indicates the presence of antibodies. A method of determining the presence of an antigen is provided wherein a sample is mixed with two classes of antibodies which are specific for the antigen being tested for, but which react with different antigen domains, wherein the mixture consists of class one antibodies bound to a transport particle which flows freely through the trapping zone and class two enzyme-linked antibodies which are incapable, unless bound to the transport particles, of flowing freely through the trapping zone.

Abstract: A method for determining thyroxine uptake of a sample serum comprising: (a) incubating the sample serum with solid phase thyroxine and labeled anti-TBG antibody; (b) separating the solid phase from the unbound labeled antibody; (c) measuring the amount of label associated with the solid phase; and (d) calculating the thyroxide uptake ratio of the sample serum by relating the measurement of step (c) to a measurement of a reference serum.

Abstract: An immunoadsorbent material for removing IgG and IgG-complexes from biological fluids is prepared by covalently binding protein A to a solid-phase silica matrix. It has been found that particularly stable, high-capacity immunoadsorbents are obtained by derivatizing the silica with amino and/or carboxyl groups, and reacting the protein A with a carbodiimide at a pH in the range from 3.5 to 4.5. Binding through free hydroxyl groups may be achieved with cyanogen halides at a pH in the range from 11.0 to 11.5. After acid washing (pH 2.0-2.5) to remove non-covalently bound protein A, the immunoadsorbent may be employed in a column for therapeutic treatment of various cancers and autoimmune disorders where IgG-complexes are implicated as suppressing factors in inhibiting a normal immune response. The column has been successfully employed in treating patients suffering from Kaposi's sarcoma.

Abstract: A heterogeneous, competitive binding immunoassay for either phenytoin or phenobarbital is conducted with a labeled conjugate comprising a derivative of hydantoin and a label. The hydantoin derivative is 5-ethyl,5-phenyl hydantoin and it is linked to the label (e.g. an enzyme) with a linkage derived from an aliphatic monocarboxylic acid. The immunoassay can be carried out either in solution or with a dry analytical element.

Abstract: Agglutination assays, particularly latex agglutination assays, for simultaneous testing for a multiplicity of ligands. The reagents for use in the assays comprise two or more insoluble colored substances, each substance being adapted to form a distinctively colored agglutinate in the presence of a specific ligand or specific group of ligands.

Abstract: This invention provides particle compositions possessing ferromagnetic, paramagnetic or diamagnetic properties. The particles are especially useful when used in the disease diagnostic and treatment regimens as described in U.S. Pat. Nos. 4,106,448, 4,136,683 and 4,303,636.

Abstract: Competitive or inhibition assays are disclosed in which sample (e.g., containing target antigen), a reagent containing first particles (e.g., antibody-coated light particles) and a reagent containing second particles (e.g., antigen coated heavy particles) are reacted in a centrifugal field. Differential migration of first particles, of second particles and of first particles linked to second particles leaves a concentration of particles at a locus in solution after a time, which concentration is a function of the analyte concentration in the sample.

Abstract: A sample is mixed with a reagent containing stably suspended particles coated with a binding pair member complementary to or competitive with the target binding pair member. A centrifugal force applied during reaction is sufficient to change the concentration of particles at a locus relative to overall particle concentration. Light transmission or scattering is measured kinetically at the locus, especially in a microcentrifugal analyzer.

Abstract: A method of measuring an infectious disease antibody such as syphilis IgM, which comprises treating immunoglobulins of a sample with an anti immunoglobulin antibody sensitized on carrier particles and an antigen of the infectious disease sensitized on carrier particles. According to the method of the invention, the specific antibody of the specific infectious disease such as syphilis IgM can easily and exactly be measured. This method is useful for the judging the stage of infectious disease and watching the results of treatment.

Abstract: In an immunoassay, ultrafine particles having an average particle size of 0.2 .mu.m or smaller and sensitized with a substance, which has reactivity with the materials to induce a nonspecific immunoreaction, are added to a sample to inhibit the nonspecific immunoreaction. The above immunoassay can avoid the influence of nonspecific factors more effectively, thereby permitting accurate measuremens on the concentrations of antigens in samples such as blood, urine, body fluid and the like.

Abstract: A method of measuring the result of a binding assay that does not require separation of fluorescent smaller particles is disclosed. In a competitive binding assay the smaller fluorescent particles coated with antigen compete with antigen in the sample being analyzed for available binding sites on larger particles. In a sandwich assay, the smaller, fluorescent spheres coated with antibody attach themselves to molecules containing antigen that are attached to larger spheres coated with the same antibody. The separation of unattached, fluorescent smaller particles is made unnecessary by only counting the fluorescent events triggered by the laser of a flow cytometer when the event is caused by a particle with a light scatter measurement within a certain range corresponding to the presence of larger particles.

Abstract: Viruses are detected by means of an immunoassay method in which an extended solid phase coated with antiviral antibody is employed to bind and remove virions from a specimen by forming an immuno-complex with antigens of said virions, a mobile solid phase comprising a dispersion of microspheres coated with the antiviral antibody is used to bind said microspheres to antigens associated with said immuno-complex, and the presence of bound microspheres is detected. The detection sensitivity is amplified by the ability to more readily detect the microspheres, which may be dyed or labelled. The extended solid phase advantageously may be in the form of a dipstick which can be easily contacted with the specimen. A virus detection kit provides the extended solid phase and mobile solid phases, each coated with antiviral antibodies.

Abstract: A novel agglutination assay is provided which brings together through the intermediacy of the binding of specific binding pair members particles which differ by having different members of a signal producing system. The signal producing system is characterized by having two enzymes which are related by having the product of one enzyme being the substrate of the other, where the reaction of the second enzyme results in a product providing a detectable signal, desirably including a scavenger for the product of the first enzyme. The amount of product providing the detectable signal which is produced is related to the amount of analyte in the media. The composition and ratio of particles can be provided in reagent kits to optimize the assay results.

Abstract: A method is provided for solid phase immunoassay for quantitation of antigen, hapten or antibody analyte in liquid sample and alternatively for quantitation of analyte occuring on or attached to cells or other particulate material in a liquid sample. The solid phase is suspended for at least the initial reactions and is subsequently concentrated by microfiltration to a volume substantially less than the sample volume. Luminescence of substantially the entire label on the concentrated solid phase is measured.

Abstract: Assays are provided employing particles and absorbent particles, wherein the absorbent particles substantially inhibit fluorescence when bound to the fluorescent particles through specific non-covalent binding.

Abstract: A method and device for detecting an antigenic material in which the device comprises a test utensil having an indentation in which two reagent spots are placed, the first body being a dyed substrate having a coating of an antibody or antibody-like material thereon and the second of the two reagent spots comprising a dyed test-inert material or a dyed substrate with a coating of a normal animal serum, the dye employed in the second reagent spot having a different color than that employed in the first spot. When a liquid test sample is added to the indentation, the dyed substrate particles or components are suspended or solubilized, and the resulting suspension gives the appearance of a third color. A positive agglutination test is indicated by the formation of at least one spot having the color of the first dyed substrate against a background having the color of the second dyed substrate.

Abstract: An immunoassay by which a plurality of kinds of antigens or antibodies in one test sample may be simultaneously quantified. Each of a plurality of kinds of microcapsules is first provided for each kind of a plurality of antigens or antibodies to be quantified such that the microcapsules bind an antibody or antigen specific to one kind of the plurality of antigens or antibodies to be quantified. The microcapsules are formed of a membrane capable of being lysed by the complement activity, and each kind of microcapsules contains therein a substance that is quantifiable and does not interact with another quantifiable substance contained in other kinds of microcapsules. The plurality of kinds of microcapsules are mixed with a test sample and complement, and the quantifiable substances are released from the microcapsules upon lysis of the microcapsules by the complement activity. The quantifiable substances are then quantified.

Abstract: A direct particle agglutination immunoassay for assaying an antigenic substance (Ag) in a fluid. The immunoassay is the type which comprises:(a) contacting the fluid with an antibody (Ab) coated particle (P) to agglutinate the Ab coated particles; and(b) detecting the presence of agglutination.The immunoassay is characterized in that the fluid is contacted with at least one additional entity selected from a group consisting of at least one different type of antibody (Ab.sub.a) coated particle (P.sub.1) and at least one different type of antibody (Ab.sub.b). The P.sub.1 is selected from a group consisting of P, at least one different particle (P.sub.2), and mixtures thereof (P and P.sub.2). Each type of Ab.sub.a -P.sub.1 and Ab.sub.b has a lower average affinity constant (K) for Ag than the K of Ab-P and the additional entity is present in an amount sufficient to avoid a high antigen false negative effect.Also, a reagent of the type comprising Ab-P.

Abstract: A process for producing an adult T cell leukemia associated antigen is disclosed wherein an adult T cell leukemia associated antigen producing cell is treated with a surfactant. A method for assaying adult T cell leukemia associated antibodies by enzymoimmunoassay, radioimmunoassay or passive hemagglutination is also disclosed. In this method, the adult T cell leukemia associated antigen obtained by treating the adult T cell leukemia associated antigen producing cells with a surfactant is used as the antigen in the assay procedure.

Abstract: Methods are provided for rapidly determining a number of parameters in a few determinations. Particularly, the method is applicable to blood typing, determining the blood type as to the ABO and Rh type, as well as the determination of isoantibodies to the antigens. The method employs fluorescent particles having a plurality of fluorescers, where the presence or absence of light emission of a particular wavelength can be determined.

Abstract: A biologically active composition comprising an immobilized phase comprising an antigen or an antibody, and an immobilized phase comprising an enzyme, an enzyme inhibitor or activator, and a method of measuring antigen or antibody using the same. According to the method of the invention, antigen with antibody can be detected in a simple procedure and high sensitivity.

Abstract: An assay for simultaneously determining the ratio of B cells and T cells to the total cell population and subpopulations thereof present in a lymphocyte population utilizes excess amounts of B cell binding protein and T cell binding protein bound to solid phase particles. By exposing the particles to the lymphocyte population, rosettes are formed which may be visually distinguished and counted under a microscope, yielding the proportions of B cells and T cells, including any subpopulations for which a specific label was provided. Macrophages may be identified by their ability to ingest the particles.

Abstract: "Two-site" or "sandwich" immunometric assay techniques for determination of the presence and/or concentration of antigenic substances in fluids using monoclonal antibodies are described and compared to conventional assays using polyclonal antibodies. Also described are inhibition assays using complexes of antigens with a monoclonal antibody.

Abstract: Method of making and using products for analysis of specific ligands in solution. More specifically, a method of analyzing a sample for a ligand by incubating the sample with a ligand selective binder and with a predetermined amount of ligand, the binder and/or the predetermined amount of ligand being borne by particles of predetermined size, filtering the solution and analyzing the particles which pass through the filter and/or those particles that do not pass through the filter.

Abstract: A concept and various means of immunological assay are disclosed wherein two different classes of particles which interact at short distances to produce characteristic detectable signals are employed in a modification of the usual latex fixation test. In one embodiment of the concept an aqueous suspension of appropriately coated tritiated latex particles (LH) and polystyrene scintillant particles (L*) is employed. The amount of (LH) (L*) dimer formation and higher order aggregation induced and therefore the concentration of antibody (or antigen) present which caused the aggregation can be determined by using standard liquid scintillation counting equipment. Also, an optical container for use in the assay which has one side provided with a section forming a quadrilateral prism with the prism providing for an angle of incidence greater than the critical angle for an electromagnetic beam of radiation.