Abstract: A buffered aqueous composition is useful simultaneously as a wash solution and a dye-providing composition in specific binding assays involving enzyme-labeled specific binding reagents. The wash composition includes a dye-providing composition, a buffer and an organic solvent having a certain molecular weight and water-solubility. Another useful composition includes a particulate substrate having avidin attached thereto, and a peroxidase reducing agent. Either composition can be provided in a diagnostic test kit, and can be used to detect a specific binding ligand in assays.

Abstract: Chemotherapy agents of interest are tested in untreated tumor cells and in tumor cells pretreated with buthionine sulfoximine (BSO) which reverses resistance related to elevated glutathione levels, and/or calcium channel blockers such as Verapamil which reduce resistance related to p-glycoprotein levels. The results of the several tests are then integrated to provide a predictor of tumor drug sensitivity and the potential utility of pretreatment regimens.

Abstract: In one aspect, a kit for the semi-quantitative measurement, in a liquid sample, by competitive immunoassay, of a first member of a specific binding pair, the kit including a solid support bearinga reference area which provides a detectable signal in the immunoassay, anda first and a second test area exposed to contact the sample, each test area containing a different amount of second or first member of the specific binding pair,whereby the intensity of the detectable signal from the reference area can be compared with the intensity of any detectable signals from the first and second test areas in the presence of an unknown quantity of the first member in the sample.

Abstract: The invention is an apparatus useful in carrying out an analytical assay. The apparatus has a positive and negative control, as well as a site for determining the presence, amount, or lack of an analyte in a sample.

Abstract: An improved screening test method and kit for cancerous and precancerous conditions which is rapid, employs reagents which can be provided in kit form and which does not give false negatives due to sampling error, immobilizes a sample of a proteinaceous body fluid in a membrane filter, tests for marker carbohydrates therein which have vicinal galactose moieties and which are enzymatically oxidized with galactose oxidase to vicinal aldehydic moieties which then visualizes any thus-produced vicinal aldehydic moieties with Schiff's Reagent, then further oxidizes those samples which test negative for the marker carbohydrates with periodic acid, thereby rendering the sample visualizable with Schiff's Reagent if the sample contains glycoprotein, which applies the galactose oxidase directly to the membrane filter, thereby speeding up color developed, and employs Schiff's Reagent which was refrigerated after preparation until its color faded to a straw shade before being treated with activated charcoal, which treatme

Abstract: A standard solution containing thyroxine-binding globulin (TBG) and thyroxine or triiodothyronine dissolved in a buffer solution is used for calibration in a method for the determination of thyroxine (T.sub.4) or triiodothyronine (T.sub.3) in serum, wherein both human and bovine TBG can be used.

Abstract: An assay method and compositions are provided for determining the presence of an analyte in a sample. The analyte is a member of an immunological pair (mip) comprising ligand and receptor. By providing a first measurement surface capable of specifically binding a labelled reagent in an amount depending upon the presence of analyte in the sample and a second calibration surface capable of binding a second labeled reagent in a manner unaffected by the presence of analyte in the sample, calibration of individual tests can be accomplished simulataneously with the performance of the test itself. A signal producing system includes an enzyme bonded to a mip which defines the first labeled reagent for binding to the measurement surface and the same enzyme conjugated to a ligand capable of binding to the calibration surface. Preferably, both labeled reagents have the same composition and the calibration surface includes anti-(first enzyme).

Abstract: A method is provided for rapidly determining during a saliva specimen collection procedure the presence of an amount of saliva, and for verifying that the sample obtained is in fact saliva. Color indication by dye markers and/or enzymatic activation of color indicators provides an indication that at least a predetermined amount of saliva has been applied to an absorbent and the enzymatic reaction indicates that saliva is contained in the sample collected.

Abstract: A method of screening for the endometrial cancer cells in a endometrial cell specimen is disclosed. The method involves determining the amount of an endometrial cancer associated antigen relative to the sample amount by immunologically detecting and comparing the levels of the endometrial cancer associated antigen and a substance present in human cells in a substantially constant amount.

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: The invention relates to a method of preparing a reagent for the determination by hemagglutination of antibodies to bacterial toxins. According to this method erythrocytes are treated with glutaraldehyde and then with the bacterial toxins in the presence of glutaraldehyde without a wash step. The reagent thus obtained is further treated with a reagent for blocking aldehyde groups.

Abstract: The present invention discloses a DNA marker ladder useful in Southern blot hybridizations. The ladder is made up of pooled DNA restriction endonuclease digests, where each restriction digest contains at least one fragment complementary to a probe and at least one fragment not complementary to the probe. The regions of complementarity between the probe and the complementary fragments are double-stranded segments of the fragments. The ladder is characterized by an approximately even spacing of bands, resulting from choosing fragments having an logarithmic size distribution. Kits incorporating this ladder and a probe or means for making a probe or a probe and a means for labeling a probe are also disclosed.

Abstract: The novel analytical devices and methods of the present invention involve dual pathway devices which provide for the confirmation of sandwich or competitive assay results. In a self-confirming sandwich assay, the labeled analyte complex becomes immobilized within a first pathway at an assay capture site to indicate the presence or amount of an analyte in the test sample. In a second pathway, a confirmatory reagent blocks the binding of the analyte or labeled analyte complex to a confirming assay site, thereby confirming that the presence of label in the assay capture site indicates a positive test sample. In a self-confirming competitive assay, a confirmed positive result is one in which the device displays a decrease in signal or no signal at the assay capture site, and the confirming assay site displays a detectable signal.

Abstract: The invention teaches a method for determining an analyte in a liquid sample via a heterogeneous assay. The sample is contacted to a carrier material which contains, in addition to one of a labelled analyte analogous substance or a labelled analyte specific substance, a detectable component which does not influence immunological reactions occurring during the course of the assay. A solid phase bound component, which is either an insufficient amount of analyte specific substance or an excess of analyte relative to analyte in the sample is contacted to the sample so as to accomplish formation of solid phase bound complexes. After separation of liquid and solid phase, label is measured in one of these, and the detectable substance is measured in the liquid. Correlation of the values obtained leads to determination of the analyte. Also described is a reagent used in the described method.

Abstract: The present invention is directed to a method for assessing the reliability of DNA sizing measurements performed on DNA samples. DNA sizing control standards are disclosed wherein each standard contains a unique set of DNA restriction fragments composed of coding fragments and measuring fragments of known sizes. Methods for constructing the fragments which can be used in making the DNA sizing control standards are disclosed. Kits comprising the DNA sizing control standards of the present invention are also disclosed.

Abstract: The present invention is concerned with a combination for the preservation of diagnostic tests, characterized by a content of at least two components selected from the group comprising 2-methyl-4-isothiazolin-3-one hydrochloride, 2-hydroxypyridine-N-oxide, chloroacetamide, (N,N-methylene-bis-(N-(1-hydroxymethyl-2,5-dioxo-4-imidazolidinyl))-urea and 5-bromo-5-nitro-1,3-dioxan.The present invention is also concerned with a preserved diagnostic test kit, comprising test reagents and at least two preservation agents selected from the group comprising 2-methyl-4-isothiazolin-3-one hydrochloride, 2-hydroxypyridine-N-oxide, chloroacetamide, (N,N-methylene-bis-(N-(1-hydroxymethyl)-2,5-dioxo-4-imidazolidinyl))-urea and 5-bromo-5-nitro-1,3-dioxan.

Abstract: Immunoassay process for the detection of an antigen in a sample of blood, serum, urine and other liquids employing a test apparatus comprising a reaction chamber and a support element in the reaction chamber comprising a blend of from about 5 to 95 percent cellulose organic ester fibrets and from about 95 to 5 percent by weight of a dispersible cut fibers where a predetermined amount of an antibody capable of extracting an antigen from the sample is bound to the support element, the process comprising depositing the sample on the upper surface of the support element and detecting the amount of antigen in the sample.

Abstract: The type of a blood specimen is determined by adding a portion thereof, either a diluted solution of its red cells or a portion of its plasma, to each of a multiplicity of wells in a transparent tray, by adding a blood type specific reagent to each of the wells in the tray, different reagents being added to different ones of the wells of the tray, periodically tilting the tray at a substantial angle of at least approximately 50.degree.

Abstract: A method for determining the sensitivity and/or specificity of assays that detect the presence or absence of antibodies to viral and/or other microbial infective agents using porcine seroconversion panels, and production of the seroconversion panels is provided.

Abstract: This invention provides a method as well as a kit for diagnosing Alzheimer's disease. The method comprises the steps of obtaining a non-neural tissue biopsy sample, contacting at least a portion of the sample with a quantity of antibodies capable of identifying .beta.AP, a .beta.-amyloid precursor protein fragment comprising .beta.AP, or a .beta.AP peptide fragment of about 8 or more amino acids sufficient to allow detection of said protein, protein fragment or peptide fragment, and monitoring the extent of the reaction between the sample and the antibodies. The kit comprises antibodies specific for .beta.-amyloid protein, or a .beta.-amyloid precursor protein fragment comprising .beta.-amyloid protein, or a peptide fragment of .beta.-amyloid protein of at least about eight amino acids, and a means for detecting the extent of the reaction of the antibodies with a non-neural tissue sample.

Abstract: Alkaline phosphatase to which is covalently bound a carbohydrate of the general formula ##STR1## wherein n is 0, 1, 2 or 3, A is an acyl radical containing 2 to 5 carbon atoms, R.sup.1 and R.sup.2 are each hydrogen atoms or hydroxyl groups, R.sup.3 is --COOH or --CH.sub.2 OH, R.sup.4 is a hydroxyl group or a --CHOH--CHOH--CH.sub.2 OH or --NH--CO--CH.sub.2 --CH(NH.sub.2)--COOH radical or a complex containing the carbohydrate, is used as a standard for the determination of human alkaline phosphate. Preferred carbohydrates are ovomucoid, chitobiose, chitotriose or N-acetylglucosamine-N-acetylneuraminic acid.

Abstract: A stabilized prolactin calibrator is disclosed. The calibrator has a pH from about 5.5 to about 9.0, and contains prolactin in a 0.01 M to 0.2 M matrix of tris-(hydroxymethyl)aminomethane which additionally contains about 0.3 to 4 percent of bovine serum albumin, about 0.05 to 0.2 percent of sodium azide and from about 0.01 to about 0.2 mole/liter NaCl.

Abstract: Indirect method of detecting elastase-modified or cleaved, antithrombin (ATx) in the presence of intact antithrombin (AT-III). The inventive method includes a modified ELISA using a detergent to alter the intact AT-III. Cleaved AT-III is generated in human plasma, then an ELISA is performed in the presence of a detergent.

Abstract: A microassay card for a includes an upper layer containing wells for receiving a liquid sample. A second layer of the card, beneath the first layer, includes a supporting surface bound to a reactive species. A third layer includes a superabsorbent support impregnated with an indicator. Typically, the indicator is a substrate for an enzyme, such as a reduced dye precursor and a source of hydrogen peroxide necessary for the action of the enzyme upon the substrate to cause a spectral change in the absorbent layer. By selecting the structure of the first and second layers, the card can be formatted for a displacement assay or a competitive assay. The microassay card of the present invention is particularly useful for drug testing.

Abstract: Antigenic compositions useful in diagnostic testing for the presence of Campylobacter jejuni or Campylobacter coli comprising a PEB1 antigen obtained from Campylobacter jejuni having an apparent molecular weight of about 28 kDa as measured by SDS-PAGE under reducing conditions, a molecular weight of 28.9 .+-.1.0 kDa as measured by gel filtration chromatography under native conditions and an isoelectric point of 8.5 or a PEB3 antigen obtained from Campylobacter jejuni having an apparent molecular weight of about 30 kDa as measured by SDS-PAGE under reducing conditions and an isoelectric point of greater than 9.3 or a combination thereof.

Abstract: The invention is a method for measuring a hapten poorly soluble in aqueous solution in a sample which includes the steps of reacting the hapten with an antibody specific for the hapten; and comparing the result of the reaction of the hapten and the antibody with the result of the reaction of the antibody and a water-soluble conjugate of the hapten and a water-soluble macromolecule having a molecular weight greater than about 1,000.

Abstract: A method for determining the adequacy of a cervical or urethral test specimen collected for an immunological assay to detect the presence of Chlamydia trachomatis. Cells present in the specimen are disrupted to expose a substance present in or on C. triachomatis that is detectable by immunological reaction. In order to determine if the test specimen contains an adequate amount of the cervical or urethral cell type that serves as a host cell for C. trachomatis, the disrupted specimen is also reacted with an immunological reagent that produces a detectable complex upon specific binding with a substance present in or on columnar epithelial cells. The present invention therefore provides a control reaction that verifies the adequacy of the collected test specimen and thereby increases the confidence that a negative test result for the presence of Chlamydia indicates the absence of a C. trachomatis infection in the patient.

Abstract: An assay method and compositions are provided for determining the presence of an analyte in a sample. The analyte is a member of an immunological pair (mip) comprising ligand and receptor. By providing a first measurement surface capable of specifically binding a labelled reagent in an amount depending upon the presence of analyte in the sample and a second calibration surface capable of binding a second labelled reagent in a manner unaffected by the presence of analyte in the sample, calibration of individual tests can be accomplished simultaneously with the performance of the test itself. A signal producing system includes an enzyme, a catalyst usually bonded to a mip which defines the first labeled reagent for binding to the measurement surface and the same catalyst conjugated to a ligand capable of binding to the calibration surface. Preferably, both labeled reagents have the same composition and the calibration surface includes anti-(first catalyst).

Abstract: Erroneous-positive results free method for the detection of moulds in foodstuffs and in human and animal body fluids with the aid of an immunological determination of the extracellular polysaccharide (EPS) produced by the mould; this method is characterized in that (a) an immunological determination of the EPS produced by the mould is carried out and, in the case of a positive result, subsequently (b) an immunological determination is carried out in the presence of a synthetically prepared epitope of the EPS investigated and the EPS investigated itself.

Abstract: The invention relates to assays utilizing microparticle separation. More particularly, the invention relates to microparticle assays used for confirmation of ligands in a biological sample.

Abstract: An aqueous wash solution is useful for the detection of herpes simplex virus in a biological specimen. This solution has a pH of from about 9 to about 11.5, and consists essentially of an alcoholamine or a salt thereof and a nonionic surfactant. The solution is used to wash uncomplexed materials from a complex of herpes simplex antigen and antibodies thereto. The wash solution can be supplied as part of a diagnostic test kit.

Abstract: The present invention relates to improved specific binding assay methods, kits and devices utilizing chromatographically mobile specific binding reagents labelled with colloidal particles. Specific binding reagents labelled with colloidal particles such as gold and selenium may be subjected to rapid chromatographic solvent transport on chromatographic media by means of selected solvents and chromatographic transport facilitating agents. Further, impregnation of solid substrate materials with labile protein materials including colloidal particle and enzyme labelled reagents in the presence of meta-soluble proteins provides for the rapid resolubilization of such materials which have been dried onto such substrate materials.

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 behaviour 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: A kit of highly uniform size microbead standards for flow cytometer alignment, compensation, and/or calibration, comprising a blank microbead population and/or an auto-fluorescent microbead population, together with two or more series of calibrated microbead populations labeled with fluorescent dye(s) which (i) prior to fluorescent dye(s) labeling, match the fluorescence spectra and fluorescence intensity of the blank and/or autofluorescent microbead population, and (ii) after fluorescent dye(s) labeling, match the fluorescence spectra and fluorescence intensity of fluorescently labeled samples to be measured on the flow cytometer. Also disclosed is a corresponding method to align, compensate, and/or calibrate a flow cytometer so as to make measurements on samples comparable and independent of the specific instrument and instrument settings.

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: A qualitative and quantitative method of determining the fluorescence threshold of an instrument and of determining whether the instrument is sensitive enough to measure the autofluorescence of a sample. The method utilizes non-fluorescent particles such a microbeads which are run on a flow cytometer. The peak channel position of the microbeads is used as the fluorescence threshold.

Abstract: The use of a combination of calibrated microbead populations with one or more calibrated biological cell populations to correct calibration of a flow cytometer for size and fluorescence intensity determinations of biological cell samples. The use of calibrated biological cells permits correction for factors related to the instrument and calibration microbeads so long as the excitation and emission spectra of the calibration microbeads, the calibration cells and the cell samples are all the same, respectively.

Abstract: A method of, and a device for performing immune enzyme analyses are described, wherein positiveness or negativeness of an analysis is evaluated by colorimetric comparison of a chromogen zone of determination with a chromogen zone of reference, on which zones reactions are occurring, or not, between the chromogen system and an enzyme conjugated with immunoreactive substances which will reach said zones in different quantities when a sample to be analyzed contains the analyte of which it is desired to acertain the presence.

Abstract: Highly uniform microbeads containing a single fluorescence dye or a mixture of fluorescence dyes, which can be excited over a wide range of the spectrum extending from the ultraviolet to the infrared, and which can be used to align a flow cytometer or fluorescence microscope.

Abstract: A method for performing an assay to differentiate between related taxa of micoorganisms, comprising the steps of providing a support having a plurality of zones, each zone comprising immobilized antibody to an enzyme found in a particular microorganism, wherein the antibody in the zone is specific to the enzyme, but not to corresponding enzyme of other taxa to be determined in the assay; contacting the zones with a sample suspected of containing one of the particular microorganisms; permitting enzyme in the sample to become bound by antibody in one or more of the zones; and determining which of the taxa were present in the sample by determining to which of the zones the enzyme has become bound. The determining step may comprise adding a substrate for the enzyme to the support after the enzyme has become bound thereto, wherein the substrate, after being acted on by the enzyme, creates a detectable signal.

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: Solvent systems for use in increasing the solubility of 3,3',5,5'-tetramethylbenzidine (TMB) and for making a permanent color record of the results of ELISAs using HRP have been developed. In the improved solvent system containing povidone, 1-ethenyl-2-pyrrolidinone polymers, TMB can be dissolved in a very small quantity of solvent, up to a concentration of 100 to 200 NM, which can then be mixed directly into an aqueous buffer without precipitating the TMB. In the solvent system for making a permanent record, alginic acid (AA), methyl vinyl ether/maleic anhydride copolymer (MVE/MAC), dextran sulfate (DS) and/or carrageenan are added to the aqueous buffer solution, with or without povidone, to form a colored precipitate with the reaction product.

Abstract: Solvent systems for use in increasing the solubility of 3,3',5,5'-tetramethylbenzidine (TMB) and for making a permanent color record of the results of ELISAs using HRP have been developed. In the improved solvent system containing povidone, 1-ethenyl-2-pyrrolidinone polymers, TMB can be dissolved in a very small quantity of solvent, up to a concentration of 100 to 200 mM, which can then be mixed directly into an aqueous buffer without precipitating the TMB. In the solvent system for making a permanent record, alginic acid (AA), methyl vinyl ether/maleic anhydride copolymer (MVE/MAC), dextran sulfate (DS) and/or carrageenan are added to the aqueous buffer solution, with or without povidone, to form a colored precipitate with the reaction product.