Abstract: Detection of bindable substances such as antibodies and antigens using enzyme linked immunosorbent assays having particular utility in home diagnostic applications. The preferred implementation of the invention is characterized by the steps of admixing a sample suspected of containing the bindable substance to be detected with an antibody-enzyme conjugate, immersing an antibody coated solid support into the mixture and then exposing the coated support to an activated chromogenic solution. The conjugate for use in the home diagnostic assay is preferably contained within a lyophilized mixture. The lyophilized mixture contains components which preserve the antibody-conjugate's reactivity and immunologic binding specificity even if the lyophilized mixture had been subjected to hot, humid environmental conditions. Active components in the lyophilized mixture include polyethylene glycol, sugars, and surfactant.

Abstract: The present invention provides a process for the determination of an antibody in human body fluids according to the immunoassay principle in which a sample containing the antibody to be determined is incubated with at least two different receptors R.sub.1 and R.sub.2, of which one receptor R.sub.1 carries an antigenic determinant specific for the antibody to be determined and one receptor R.sub.2 carries a label to form bound and unbound label, the part which contains the bound label is separated from the part which contains the unbound label and the label is measured in one of the two parts, wherein, for the control, instead of the sample, there is used a standard solution which contains a conjugate of a bindable non-human antibody or a Fab or F(ab').sub.2 fragment thereof which non-human component binds with a receptor R.sub.s which also binds to the antibody to be determined, and a human immunoglobulin or the Fc part thereof.

Abstract: A method for enhancing the chemiluminescent signal of an acridinium ester in a chemiluminescent reaction which comprises oxidizing the acridinium ester in the presence of an enhancer selected from the group consisting of: (a) a cationic surfactant; (b) a nonionic surfactant; and (c) a sulfated primary alcohol.

Abstract: Sensitive proteins in human biological secretion samples are preserved by dispersing them in an aqueous solution containing from 0.05 to 0.5M of a buffer which is effective to maintain the solution pH within the range of from 6.5 to 8.0; from 0.1 to 10 wt. % of a non-immune animal protein selected from the group consisting of albumin, ovalbumin, casein, glycoprotein and mixtures thereof; from 40 to 2000 kallikrein units/mL of an enzyme inhibitor of trypsin, chymotrypsin, kallikrein or plasmin; and from 0.01 to 0.1 wt. % of a bacteriostatic agent. The solution preferably also contains from 5 .mu.M to 1 mM of a protease inhibitor; and from 1 to 10 mM of a chelating agent. Optimally, the enzyme inhibitor is aprotinin, the protease inhibitor is phenylmethylsulfonylfluoride, the non-immune animal protein is bovine serum albumin, and the protease inhibitor is phenylmethylsulfonylfluoride. 0.0 to 0.15 mM of a water-soluble non-interfering salt, such as NaCl, may be desired.

Abstract: A method for producing a novel antifungal product from a Pediococcus species is described. The preferred product (AFP) comprises a compound which contains valine and lactic acid and has a molecular weight of less than about 500 daltons. The product (AFP) is particularly useful in retarding fungal growth in foods and other materials in need thereof.

Abstract: A solid-phase immunoassay is provided for determination of HIV antigens in human physiological fluid. The immunoassay is characterized by the coating of a solid substrate with a unique monoclonal antibody which recognizes a common antigenic determinant of a group of HIV core antigens and no HIV envelope antigens of HIV. The test sample preferably also is subjected to a lysing reagent prior to the incubation for uniformly dispersing antigens which may be present in the test sample.

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: An analytical element has a peroxidase-labeled ligand analog distributed within a layer comprising from 0.1 to 10.0 g/m.sup.2 of poly(vinyl-alcohol) and from 0.2 to 20.0 g/m.sup.2 of glycerol. The concentration of the glycerol must be greater than 1 times the concentration of poly(vinylalcohol) in the layer. As a result, the peroxidase retains more of its stability prior to use. Such elements can be used to determine a number of different immunologically reactive analytes, such as digoxin.

Abstract: A solid-phase immunoassay is provided for determination of members of an immunological pair such as antigen and/or antibody of a single binding pair in human physiological fluid, wherein a single immunoassay enables simultaneous detection of antigen and/or antibody of a single binding pair in a test sample which may have circulating antigen and/or antibody. The immunoassay is characterized by the addition of an amount of antigen or "spike" of the binding pair to the test sample prior to incubation of the test sample in the presence of a solid-phase absorbed antibody of the binding pair. The test sample preferably also is subjected to a lysing reagent prior to the incubation for uniformly dispensing antigens which may be present in the test sample.

Abstract: Peroxidatively active enzyme assays have a variety of clinical and industrial applications. Such assays are based on color development resulting from the addition of the appropriate substrate to the enzyme-containing medium. The stability of the said substrate and the extent of appearance of color are two serious limitations in enzyme assays. A method is disclosed herein for carrying out peroxidatively active enzyme assays when the enzyme is in free solution or in cell-bound form. Stable chemical compositions are also disclosed for use as substrates for carrying out such method.

Abstract: A latex agglutination immunoassay method for determining an analyte in a blood sample in which the pH of the reaction mixture is maintained at about 8.5 or greater in order to overcome nonspecific agglutination of latex particles by hemoglobin present in the sample. The method is particularly applicable to the determination of glycated hemoglobin, e.g., Hb Alc. In another embodiment, native hemoglobin (Ao) can be determined based on its ability to cause agglutination of latex particles suspended in an aqueous solution having a pH of about 8 or below.

Abstract: The storage stability of peroxidase-reactive luminescent cocktails which employ chemiluminescent 2,3-dihydro-1,4-phthalazinediones, oxidants reactant therewith to cause light emission in peroxidase-mediated luminescent reactions, and phenolic sensitivity enhancers is improved by maintaining the pH of the cocktail prior to use at a value in the range of about 3 to about 6 and preferably at a pH of about 5. An analyte sample may be subjected to a reaction resulting in a peroxidase-containing phase, the peroxidase content of which is related to the quantity of analyte in the sample, and the peroxidase phase may then be combined with the thus-described cocktail and an aqueous alkaline organic buffer to raise the pH of the resulting reaction mixture to a value in the range of 7-9, favoring light emission.

Abstract: The present invention provides a process for the preparation of an immuno-reactive, porous carrier material by application of a solution of a first reaction component of an immuno-reaction and of a solution of a second component of an immuno-reaction coprecipitating therewith, incubation of the carrier material impregnated with the solutions for the immuno-precipitation, optional washing and subsequent drying of the impregnated carrier material, wherein a solution of both components of the immuno-reaction is prepared, which solution contains an inhibitor for the immuno-precipitation, the carrier material is impregnated with this solution and then the immuno-precipitation is initiated by removal of the inhibitor or by removal of the inhibiting action.

Abstract: Novel formulations are provided containing conjugated or unconjugated aminoglycosides, particularly labeled glycosides, a small amount of a polyamine, and additional additives, such as buffer, salt, and inert protein. The level of immunologic activity of the aminoglycoside is retained for long periods of time when stored in glass containers.

Abstract: Fluorescence ligand binding assay of a sample containing an unknown amount of ligand is performed by making direct intensity measurements. In an immunoassay the sample is in a solution containing dye labeled analyte and an antibody specific to the analyte. Surfactant, added to the solution in an amount sufficient to form micelles, provides markedly different fluorescent intensity from bound and unbound labeled analyte if the surfactant ions and dye ions have the same charge polarity and the analyte moeity has the opposite charge polarity.

Abstract: A serum folate assay wherein the serum folate is stabilized with dimercaptosuccinic acid or thioctic acid.

Abstract: There is described a method of inhibiting glycolysis in blood samples by adding an acid to the blood sample to adjust pH of the blood to a level between 5.0 and 7.0.Collected blood samples undergo glycolysis during storage due to progress of the reaction with glycolytic enzymes with a result that glucose is reduced and lactic acid and pyruvic acid formed by the glycolysis is increased. According to the method of the invention, the glycolysis as mentioned above can be inhibited simply by adjusting pH of the blood sample so that accurate determination of the above-mentioned components are feasible. The preferred acids are citric acid, malonic acid and maleic acid. Addition of citric acid to produce a level between 1.0 and 5.0 mg/ml (blood) is especially preferable. In the method of the invention, further addition of a fluoride compound, preferably NaF, improves the glycolysis-inhibiting action.

Abstract: The present invention discloses a device and a process for quantitation of Toxoplasma gondii and Treponema pallidum antibody titer in a biological sample by immunofluorescent photometric microscopy.

Abstract: Method for carrying out immunoassays, in which method an antibody (or antigen) labeled with a tracer so as to be fluorescent is attached onto an antigen (or antibody, respectively) present at the inside wall of the measurement vessel, a liquid denser than the sample is added to the measurement vessel, which said denser liquid displaces the liquid from underneath, and both the excitation radiation is passed into the sample and the fluorescent radiation is collected to the detector through the wall or the bottom of the measurement vessel.

Abstract: Method and means in/for the immunoassay determination of (I) a bacterial polypeptide capable of binding to the Fc protion of an immunoglobulin and/or (II) the high affinity antibody to said polypeptide. The characteristic feature of the method resides in using an antibody directed against the polypeptide and having antibody activity under conditions such that the immunoglobulin potentially binding to the polypeptide will substantially not bind to the polypeptide, and carrying out the immune reaction between the antibody preparation and the corresponding polypeptide epitope under such conditions.

Abstract: An method of carrying out a fluorescence polarization immunoassay is disclosed wherein the immunoassay is conducted in the presence of from about 0.001 to about 1.0 percent (weight/volume) of dioctyl sodium sulfosuccinate. Also disclosed are reagents useful in the practice of the immunoassay method.

Abstract: A method for determining low density lipoproteins (LDLs) in a body fluid sample, as well as a reagent suited for this use, are taught. The method involves precipitating high density lipoproteins (HDLs) from the sample, using an HDL specific antibody or reactive fragment, and then determining the presence and amount of LDL in the supernatant which results. The reagent contains the HDL specific antibodies, as well as polyanions and divalent cations.

Abstract: A process for producing an antibody having a specificity to estriol-3-sulfate, which comprises administering a 6-substituted-estriol-3-sulfate protein conjugate of the formula: ##STR1## wherein A is .dbd.N--O-- or --O--CO--, n is an integer of 1 to 4 and --NH--P is the residue of a protein excluding a hydrogen atom in the amino form therefrom parenterally to a living body of a vertebrate animal so as to produce the antibody in the living body and collecting a body fluid comprising the antibody from the living body.

Abstract: A newly discovered family of AIDS-associated viruses, designated ARV, is described. The viruses were isolated from AIDS patients from San Francisco and (a) are type D retroviruses; (b) have Mg.sup.++ -dependent reverse transcriptase activity; (c) induce human multinucleated cells without immortalizing the cells; (d) are replicable in HUT-78 human T cells; and (e) induce viral protein(s) in HUT-78 that binds to Ig from AIDS patients. The infected HUT-78 cells and immunogenic polypeptides derived from the viruses are useful for diagnosing AIDS.

Abstract: A solution for blood cell storage having sugar-containing blood cell nutrients therein and additionally containing a magnesium or calcium L-ascorbate-2-phosphate salt is taught. The magnesium and calcium L-ascorbate-2-phosphate salts remain stable below pH 7 and thus permit sterilization of the solution at a pH at which degradation of both the L-ascorbate-2-phosphate salt and the nutrient sugar present in the solution is substantially avoided.

Abstract: The performance of immunoassays for the analysis of serum analytes can be significantly improved by the pretreatment of the sample. Analyte in serum samples is often complexed with serum antibody. Such analyte-antibody complexes can mask the analyte and interfere with analyte specific binding steps of many immunoassays. The serum pretreatment method employs pH dependent chaotropes to dissociate the analyte-antibody complexes in the serum. At low pH, the complexes become dissociated and the antibody becomes denatured. After the dissociation and denaturation of the serum antibody, the serum sample and the chaotrope, contained therein, are then neutralized. Since the serum antibody has been denatured, it does not re-associate with the analyte upon neutralization. After the neutralization step, serum sample can then be analyzed by an immunoassay, without interference from serum antibody. A serum pretreatment kit is essential to the employment of the serum pretreatment method.

Abstract: A method for the quantification of an antigen, antibody, or antigen-antibody complex in a sample solution involving measuring the results of an immunochemical agglutination reaction or an agglutination inhibition reaction by spectrophotometry, wherein after the initiation of the agglutination between the antigen, antibody, or antigen-antibody complex to be determined and sensitized carrier particles to which a substance specifically bindable to the said antigen, antibody, or antigen-antibody complex is bound, a fixing compound is added to fix aggregates formed by the agglutination. A measuring reagent kit or pack includes all the components for use in carrying out the above method.

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: There are disclosed a method for assaying antigens or antibodies in the reaction medium, characterized in that a sample containing antigens or antibodies to be assayed is treated with a polyanion which is soluble in the reaction medium and thus treated sample is used for the antigen-antibody reaction; and a reagent for assaying an antigen-antibody reaction, which contains a polyanion and a reaction medium.

Abstract: Compounds useful in a simultaneous multiple assay for analytes such as steroids, proteins, peptides, carbohydrates or drugs. The compound or compounds are prepared by labelling an individual analyte with a radioisotope through a chelating agent to form a coordinated compound. The assay uses one or more chelated labelled analytes with one or more labelled analytes wherein each radioisotope is different.

Abstract: A biochemical detection method in which a ligand is bound to a surface, an aqueous solution containing an antiligand is brought into contact therewith whereby antiligand becomes bound to ligand, the aqueous solution is separated from the thus bound antiligand, and the antiligand is detected using a detection means associated therewith, for example using amplified enzyme-linked immunoassay. The surface is treated with at least one agent for limiting non-specific binding of either the ligand or the antiligand with other substrates, which agent is(i) a surfactant containing an aromatic residue and having an HLB number of at least 16,(ii) a zwitterionic surfactant, or(iii) a solution containing a salt of a polyvalent anion, in a concentration of at least 100 mM.Preferably, all three agents are used simultaneously. The three agents may be used during the detection procedure in solutions containing the antiligand, in washing solutions used during the method, or in solutions used to pre-treat the plate.

Abstract: A heterogeneous binding assay in which a liquid component and a granular particulate solid phase are incubated together for a predetermined period of time. To prevent unwanted unit gravity sedimentation of the granular particulate solid phase during incubation the density of the liquid component is controlled such that it is substantially equal to the density of the granular particulate solid phase, thus preventing sedimentation. The density may be controlled by adding a density modifying medium such as a colloidal suspension of silica particles coated with polyvinylpyrrolidine. After incubation, the density of the liquid component may be reduced allowing unit gravity sedimentation and hence separation of the solid phase from the liquid component. The assay is particularly applicable to immunoassay (for example radioimmunoassay and immunoradiometric assay). Immunoradiometric assays for human growth hormone, thyroid stimulating hormone and alphafetoprotein are described.

Abstract: A solution containing from about 0.25% to about 5% hydrolyzed ovalbumin by weight provides surprising thermal stabilization of monoclonal antibodies.

Abstract: Fluorescence ligand binding assay of a sample containing an unknown amount of ligand may be performed by making direct intensity measurements. In an immunoassay, for example, the sample may be added to a solution containing fluorescein labeled analyte and then is added an antibody specific to the analyte. Sodium dodecyl sulfate, a surfactant, added to the solution in an amount sufficient to form micelles provides markedly different fluorescent intensity from bound and unbound labeled analyte.

Abstract: The invention is an improvement in a heterogeneous immunoassay, and reagent therefore, for the determination of a substance in a blood serum or plasma sample, such as a parnter of an immune reaction, in which one of the reaction partners is adsorbed on a solid carrier, the improvement comprises adding a detergent to the incubation medium of the reaction, in an amount of 0.0001 to 0.01% (w/v) to reduce interferences from the serum or plasma.

Abstract: A process of carrying out a specific binding assay, for the qualitative detection or quantitative or semi-quantitative determination of an analyte which forms a component of a specific binding reaction, using a labelled conjugate form of a derivative or analogue of one of the relevant specific binding partners, said labelled form being capable of emitting delayed luminescence upon photo-excitation, characterized in that the labelled conjugate form of one of the relevant specific binding partners comprises a derivative or analogue of the specific binding partner with a derivative of a luminescent substance which shows a delayed light emission upon photoexcitation, the delayed light emission of which is subject to quenching by molecular oxygen, and characterized further in that the assay is carried out by the use of a time-resolved photometric method in the presence of an effective amount of a quench-inhibiting substance able to prevent quenching by molecular oxygen.

Abstract: Process for the determination of carcinoembryonic antigen (CEA) in a sample of serum or plasma. The process comprises contacting a slightly acidic buffered sample of the serum or plasma with hydrophilic silica at room temperature, separating the silica from the sample and carrying out a radioimmunoassay for carcinoembryonic antigen on said sample.

Abstract: A process for conducting fast, rapid two site, two step immunoradiometric tests for CK-MB.In a first series of steps, a mobile particulate solid-phase having an isoenzyme selected from the group of CK-BB and CK-MM immobilying bound on its surface is suspended in a matrix of pooled match human serum. The mixture is incubated, diluted, and centrifuged.In a second series of steps, the resulting solid is incubated with a radio labeled antibody that is specific to the isoenzyme not used in the first series of steps. Counting the radioactivity gives the amount of CK-MB in the patients serum.

Abstract: The present invention discloses a device and a process for quantitation of end point in the formation of fluorescent reaction product in microfluorophotometry. The process comprises:(a) incorporating a protective agent in a suitable mounting medium in an amount sufficient to reduce fading of fluorescent reaction product less than 25% of initial fluorescent intensity;(b) calibrating photometer used in said microscopy with a stable emitter; and(c) recording the intensity of fluorescence of said fluorescent reaction product by means for measuring light intensity.The invention also includes a device for calibration of the photometer and a kit comprising separate containers for suitable mounting medium, buffer, suitable immunofluorescent reagents, fading retardant means, a photometer calibrating device and the like and optional instructions.

Abstract: A process for `unmasking` delta antigen in the blood of an animal, known or caused to be infected with the antigen. The process involves treating serum from the animal with a surfactant and optionally with an antibody--antigen dissociating agent. The blood derived delta antigen is used as a diagnostic agent in the detection and determination of different classes of antibodies to hepatitis D. virus (delta agent) by enzyme-immunoassay and radio-immunoassay.

Abstract: Aqueous formulation containing monoclonal antibodies active against cell-bound antigens, particularly human red cell antigens, the said formulation containing a soluble salt in a concentration of not less than about 200 mmoles/1.

Abstract: A composition having a protein binding solid support onto which is bound a mixture of antigens and antibodies which are both bound to the solid support individually and are not present in the form of an immune complex.

Abstract: Competitive immunofluorescence assays for antigens in which immune complexes are precipitated with a nonfluorescent, nonlight-scattering precipitant such as polyethylene glycol and the resulting immunoprecipitate is dissolved with a nonfluorescent solvent of low ionic strength that maintains the pH of the solution substantially constant for immunofluorescence intensity reading. The assays are carried out by incubating the sample with fluorescent-labeled antigen, anti-antigen antibody, and a secondary antibody to the anti-antigen antibody followed by addition of the precipitant to form an immunoprecipitate. The precipitate is separated by centrifuging, dissolved in the solvent, and the immunofluorescence intensity of the solution is read with a fluorometer and compared to a standard curve.

Abstract: An antiserum for immunohematologic agglutination reactions involving IgG antibodies wherein reduced IgG antibodies are suspended in a low ionic strength medium.

Abstract: Improved catalyzed substrates for use in developing characteristic colors or fluorescence in the presence of peroxidase enzymes (e.g., horseradish peroxidase) are disclosed which include as a rate accelerator a substituted phenol such as a p-halogenated phenol. The complete system typically includes a peroxide type oxidizing agent (e.g., hydrogen peroxide), a chromogenic or flurogenic compound (e.g., ABTS), a buffer and the accelerator compound. Advantageously, the accelerator should provide at least about 50 percent rate enhancement for the substrate, as compared with an otherwise identical, accelerator-free substrate reacted under the same conditions; however, the most preferred accelerator, p-iodophenol, gives enhancements on the order to 1,000 percent. The invention is particularly useful in so-called ELISA determinations which involve an enzyme-linked moiety, and permit detection at very low concentration levels unobtainable with conventional colorimetric substrates.

Abstract: The present disclosure relates to a solid phase immunoassay for the detection of Chlamydia trachomatis antigens in a clinical specimen, wherein the Chlamydia trachomatis antigens to be determined are coated or adsorbed on the solid phase.

Abstract: A method for direct serum assay of steroid hormones wherein the competition from binding protein, having an affinity for complexing with the steroid hormones, is significantly eliminated by adding to the serum an artificial compound which has a greater or equal affinity for the binding protein than do the steroid hormones, and which is not immuno-reactive with the steroid hormones. Because the compound is artificial, it is non-contaminating. Levonorgestrel and norethindrone as such compounds are disclosed.

Abstract: An improved immunoassay method, reagent means, and test kit for determining an iodothyronine, e.g., thyroxine (T-4), in a biological fluid, usually serum or plasma, wherein fenclofenac and related phenylacetic acids, or salts thereof, are employed as novel blocking agents for the binding of iodothyronines to thyroxine binding protein (TBP). The present invention is particularly advantageous as applied to homogeneous competitive binding iodothyronine immunoassays wherein a spectrophotometric response is generated in the assay reaction mixture at a wavelength greater than about 300 nm, the blocking agents of the present invention having been found to have no substantial absorbance at wavelengths above 300 nm. Such homogeneous immunoassays include those which employ labels such as fluorescers, enzyme substrates, enzyme prosthetic groups, enzymes, and enzyme inhibitors.

Abstract: A solid phase-sandwich enzyme-immunoassay method for the rapid determination of carcinoembryonic antigen (CEA). The sample to be investigated is incubated with a first CEA antibody, which is bound to a water-insoluble carrier, and a second CEA antibody, to which peroxidase is bound directly or via a biotin/avidin bridge. The immunological reaction can be carried out in one or two steps. By the presence of 0.4-1.0 mol/l of phosphate ions, 0.3-0.4 mol/l of sulfate ions or 0.2-0.4 mol/l of tartrate ions in the immunological reaction or in the second step thereof (insofar as it is carried out in two steps) the incubation time period is shortened considerably. After the immunological reaction, the phases are separated, whereupon the peroxidase activity is measured either in the solid or in the liquid phase as the amount of CEA present in the sample.

Abstract: This invention relates to a highly accurate, rapid and simple estimation of thyroxine (T.sub.4) directly from blood serum and also relates to the accurate measurement of triiodo-L-thyronine (T.sub.3) directly from blood serum. More specifically, the invention relates to a rapid, specific and reliable radioimmunoassay (RIA) technique for measurement of both T.sub.4 and T.sub.3 in unextracted serum. The method requires very small amounts of serum, e.g., 25 microliters (.mu.l) to measure T.sub.4 concentration in nearly all specimens representing clinical states of eu-, hypo- and hyperthyroidism, and 250 .mu.l to measure T.sub.3 concentrations in specimens representing most clinical states.