Abstract: An immunoassay method which measures test samples at high concentration without dilution is disclosed. Said immunoassay comprises the steps of: (1) reacting a material (A) to be measured, an immobilized component (B) which binds specifically to the material (A), and a labelled component selected from the group consisting of (i) a labelled component (C) which binds specifically to the material (A) and (ii) a labelled component (A) thereby obtaining an immuno-complex and (2) detecting or measuring the labelling fragment, wherein the reaction of the material (A) with the immobilized (B) or the reaction of the material (A) with the immobilized (B) and the labelled component is carried out at a pH of 2-4.5.

Abstract: The invention relates to a process for the in vitro detection of a determined RNA, particularly of a mRNA connected with a genetic abnormality in a biological material. This process comprises a treatment of the cells contained in that material for the sake of releasing their cellular components and of exposing the RNAs yet without denaturing other nucleic acids, and then the detection operation comprising contacting RNA sought to be detected, in presence of the other cellular components, with a nucleotidic sequence complementary of the RNA sought.

Abstract: The present invention provides a method for the determination of a component of an immune reaction in a plasma sample using an immunoassay at a temperature of from 15.degree. to 40.degree. C., where one of the reactive components is in solid phase. The invention involves adding an amount of plasminogen activator sufficient to eliminate interference by fibrinogen with the component to be determined.

Abstract: Methods are disclosed for inactivating interfering binding proteins in a immunoassay for a member of a specific binding pair (sbp). The method comprises including in an assay medium containing a sample suspected of containing an sbp member and an interfering binding protein an effective amount of a water soluble compound having two substituted or unsubstituted phenyl groups linked to a common atom. When the sbp member or its sbp partner has two phenyl groups linked to a common atom, the compound has a number of groups other than hydrogen attached to the phenyl groups and the atom that differs by at least two from the number of such groups on the sbp member. When the sbp member or its sbp partner has two phenyl groups linked to a common atom and the binding protein is not an antibody, the compound has only one group other than hydrogen attached to a phenyl group or the common atom.

Abstract: The instant invention is a process for the recovery from an aqueous solution of water soluble biopolymers, in particular polysaccharides, gums, agar, agarose and starches by the addition of polyoxide solution to the biopolymer containing solution. The biopolymer is then separated and collected.

Abstract: New internal standards for use in gas chromatography/mass spectrometry test methods, comprising deuterated cannabinoids, have been developed for the analysis of tetrahydrocannabinol and its metabolites in biological fluids.

Abstract: C1-inhibitor (C1-Inh), the major regulatory protein of the classical pathway of complement activation, can be purified in a new, simplied three step procedure which includes PEG fractionation, jacalin-agarose chromatography and hydrophobic interaction chromatography on phenyl-Sepharose which takes advantage of the marked hydrophilicity of the inhibitor. This procedure has major advantages over those which have been the most frequently used. This method may be highly adaptable to bulk purification for clinical use or for performing analytical or functional studies on genetically or pathologically altered C1-Inh from clinical specimens.

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: Theophylline can be determined with an analytical element and method which utilize the inhibition, by theophylline, of alkaline phosphatase activity on an appropriate substrate. The assay is carried out at a pH of 9 or less. The element comprises a porous spreading zone, a subbing zone and at least one other zone. The zones are in fluid contact with each other. The isoenzyme of alkaline phosphatase and a suitable substrate for the isoenzyme are located in different zones of the element. The subbing zone contains polyvinylpyrrolidone and a buffer for maintaining a pH of 9 or less.

Abstract: The method described coats the interior of a tube-like support with the binding partner of the analyte. Analyte and anti-analyte-label conjugate are added. When the tube-like support is rotated end-over-end, the thin layer of analyte and conjugate readily react with the binding partners to form an immobilized label complex. When rotation stops, the reaction quenches to provide precise timing. The label complex is released and measured.

Abstract: A chromatic test device for the performance of immuno- or chemical assays wherein a unitary planar fibrous filter body incorporates a sample application zone, a separation zone and a reaction zone and the application zone is in fluid communication with a first absorbent and the reaction zone is in fluid communication with a second absorbent to establish bilateral flow of the fluid component of the sample and of the analyte applied to the zones during the performance of an assay.

Abstract: A method of measuring chain breakage in the DNA of a eucaryotic cell is disclosed. This method includes (a) contacting the cell with a stripping solution that lyses and solubilizes the cell without denaturing its DNA, thereby forming a nucleoid having a halo, (b) measuring the width of the halo, and (c) determining the number of chain breaks from the measured width. The halo includes at least one loop of undenatured DNA, and has a width related to the number of DNA chain breaks in the loop. The cell to be examined may be adhered to a support prior to its contact with the stripping solution. The number of DNA chain breaks can be determined by compairing the measured width of the nucleoid halo with a reference value.

Abstract: A single color determination method of quantization of the amount of fructosamine in a sample such as serum by removing other interfering reducing agents and developing a color with a coloring agent such as tetrazolium salt.

Abstract: Incubation media intended for solid-phase immunometric assays and containing lactoferrin are described. Compared with the media used hitherto, these incubation media have the advantage that they prevent, especially in the case where heated sample material is used in the assays, false results on determination of antigens or antibodies.

Abstract: A method for reducing the occurrence of falsely elevated results in a peroxidase-catalyzed, enzyme assay is described. Interference in an assay caused by blood or bood products in a clinical specimen is eliminated or reduced by reacting the specimen with an oxidizing agent such as sodium hypochlorite, hydrogen peroxide or sodium meta-periodate.

Abstract: An improved heterogeneous immunoassay is provided which includes the utilization of support materials capable of reversible immobilization of proteinaceous binding partners of biological material of interest and the removal of labeled complexes from these supports through the use of release reagents permitting the subsequent solution phase determination of the amount of label.

Abstract: A method of assaying a sample of whole blood for one member of a specific binding pair, the method involving treating the sample with salt to alter the red blood cells in the sample to decrease their ability to pass through filter media, exposing the resulting sample to a filter which retains the red blood cells but allows the passage therethrough of filtrate of the sample containing the member of the specific binding pair, and measuring the member of the filtrate.

Abstract: The present invention provides a process for the detection of redox reactions by introducing a redox reagent system into a test system, wherein a soluble iodate is additionally added to the test system in an amount which is in excess of the highest amount of disturbing reducing agents present in the test system.The present invention also provides a diagnostic agent for the detection of redox reactions containing a redox reagent system, wherein the test system used additionally contains an iodate which is soluble therein in an amount which is in excess of the highest amount of disturbing reducing agents present in the test system.

Abstract: A method is disclosed for the immunolocalization of epitopes of non-glucidic nature, in cellular cultures, in tissue slices, or immobilized on such supports as nitrocellulose, by means of the incubation of the sample with specific antibodies for the antigen to be immunolocalized, belonging to the class of the IgM's, and sequential treatment of concanavalin A and with an enzymatic marker capable of binding with concanavalin A, such as, e.g., peroxidase. The method comprises, before the incubation, a suitable treatment of the sample under test, e.g., with periodic acid, in order to prevent concanavalin A from binding with the carbohydrates present in the sample.

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: Serum samples for vitamin B.sub.12 analysis can be pretreated using a combination of peroxy acid and dithiothreitol. The pretreatment makes vitamin B.sub.12 bound to serum binding proteins available for analysis by any of a variety of currently available assay techniques. The pretreatment finds particular use in an assay using solid phase intrinsic factor as a specific binding protein.

Abstract: A filter providing at least two different filtering pore sizes for coarse and fine filtering, and a kit containing such filter along with an immunoassay test device containing a membrane. The membrane is used to separate bound immunoassay labels from free labels. The coarse and fine filtering are provided preferably by two different, serially arranged filters, the filter with the fine pore size being selected with a pore size similar to that of the membrane of the assay device.

Abstract: A biological fluid from a first animal species (e.g. human serum) is assayed for an immunogen therein by mixing with the fluid (Ig-minus-Fc) fragments of an immunoglobulin from a second animal species (e.g. rabbit), the immunoglobulin being immunospecific to the immunogen or another component of the mixture whereby the immunogen can be determined. Interference can occur from reaction between first animal species antibodies and the said fragments, and in the method of the invention this interference is avoided or overcome, preferably by also including in the mixture different (Ig-minus-Fc) immunoglobulin fragments from the second animal species which react with said antibodies but not with said immunogen. These different fragments are preferably aggregated. The method of the invention is particularly applicable to particle agglutination assays.

Abstract: Method for determining levels of sulfhydryl amino acids, particularly total homocysteine levels in samples of body tissue from warm-blooded animals, methods of detecting cobalamin and folic acid deficiency using an assay for total homocysteine levels, and methods for distinguishing cobalamin from folic acid deficiency using an assay for total homocysteine levels in conjunction with an assay for methylmalonic acid.

Abstract: A method of assaying a sample of whole blood for one member of a specific binding pair, the method involving treating the sample with salt to alter the red blood cells in the sample to decrease their ability to pass through filter media, exposing the resulting sample to a filter which retains the red blood cells but allows the passage therethrough of filtrate of the sample containing the member of the specific binding pair, and measuring the member of the filtrate.

Abstract: The present invention is directed to a fluorescence polarization assay for opiate alkaloids and their metabolites, to the various components needed for preparing and carrying out such an assay and to methods of making these components. Specifically, tracers, immunogens and antibodies are disclosed, as well as methods for making them. The tracers and the immunogens are made from substituted opiate alkaloids. A fluorescein moiety is included in the tracers, while a poly(amino acid) forms a part of the immunogens. The assay is conducted by measuring the degree of polarization retention of the fluorescence resulting when a sample mixed with antiserum and tracer is irradiated with plane-polarized light.

Abstract: A method and kit are described for detecting the presence of cancers and pre-neoplastic cells that produce an oncofetal phosphoprotein having a molecular weight of approximately 60,000 and having the capacity to increase the release of ribonucleic acid from cell nuclei. The method involves detecting the presence of auto-antibodies to this oncofetal phosphoprotein in a subject suspected of suffering from a cancer or pre-neoplastic cells which produce this cancer marker protein. The kit includes purified oncofetal phosphoprotein.

Abstract: An improved method of detecting, in a beta.sub.2 m containing clinical sample, a virus of the herpes group or an antibody to that virus, by assaying the sample with a reagent that will reveal the presence of the virus or antibody comprising, utilizing or removing the beta.sub.2 m prior to the assay by(1) removing beta.sub.2 m from at least the sample and reagent, or(2) contacting a sample that is to be assayed for virus with a reagent that reacts with beta.sub.2 m and which will form an anti-beta.sub.2 m/beta.sub.2 m/virus conjugate.

Abstract: Immunoglobulins are purified by adsorption upon and adsorbent therefor using a buffer having a pH value of about pH 6 to pH 10 and containing at least one polycarboxylic acid in a concentration of about 0.5 M to about 0.9 M.

Abstract: A method for detection of occult blood in a fecal sample which comprises acting a glycosidase type bacteriolytic enzyme on the fecal sample and subjecting the resulting fecal sample to simultaneous detection of hemoglobin, preferably in combination with transferrin, by an immunological measurement procedure.

Abstract: An immunoassay procedure for the detection of chlamydia trachomatis antigen in a urogenital clinical specimen including a method for substantially eliminating the occurrence of false negative and false positive results of the immunoassay procedure. The method comprises treating a patent specimen with an aqueous solution having a final concentration of 0.1M NaOH or 0.1M KOH and then neutralizing the specimen-containing solution before conducting the immunoassay.

Abstract: A reagent for use in immunoassays for rheumatoid factor (RF) is provided. The reagent contains heparin. Use of this reagent suppresses interference from the component Glq found in some test samples, and alleviates the need for a heat inactivation pretreatment of test samples to eliminate Clq interference.

Abstract: A CEA immunoassay includes a step for inactivation of interfering human antibodies against non-human immunoglobulin, wherein a buffered serum or plasma sample at about pH 5.0 is heated at about 90.degree. C. for about 15 minutes prior to sandwich assay using capture and probe monoclonals that bind to heat-stable CEA epitopes.

Abstract: A method and apparatus for use in quantifying, in a whole blood sample in which the red cells are lysed, a component which will react with a reagent to form an antigen-antibody complex, the method comprising mixing the sample with the reagent to obtain the complex, exposing the sample to a source of radiation and measuring the intensity of radiation scattered through a given angle by the complex, and the apparatus including a container for receiving the sample which has been treated with the reagent to the component, the container being transparent to radiation having a wavelength falling within a given band width, typically 460-530 nm. A source of radiation within this band width is provided together with a device for detecting the intensity of radiation scattered through a given angle by the sample.

Abstract: A porous chemically activated medium having a low affinity for peptide group-containing materials is provided comprising a porous polymeric medium having a low affinity for peptide group-containing materials covalently bound to a residue of an activating agent which is capable of reacting with an acceptor molecule.

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 immunoassay for trichothecenes that have at least three hydroxyl groups at specified positions is disclosed. It relies on developing antibodies to close trichothecene variants that are missing at least one of the hydroxyl groups, and then using these antibodies to test specimens in which the trichothecene has been converted to the variant (usually to the OAC variant). For example, DON and T-2 tetraol can be assayed for using this invention.

Abstract: Method for carrying out immunochemical assays for lipoproteins and/or apolipoproteins, wherein prior to the reaction of the sample with the appropriate anti(apolipoprotein) or anti(lipoprotein) antibody the pH of the sample is maintained at a non-denaturing value in a pretreatment step for exposing antigenic determinants, said non-denaturing value lying above pH 9.0 or below pH 3.0. After the pre-treatment step the pH is adjusted for immune reaction, so that then the immunochemical assay can be carried out in a manner known per se.

Abstract: Methods of preparing glucitollysinehemoglobin from a sample of glucohemoglobin containing stable and labile glucohemoglobins and for assaying for the presence of stable glucohemoglobin are disclosed, as is a diagnostic assay system useful for carrying out the methods.

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: An affinity matrix and a method for the detection of low molecular weight compositions such as aflatoxins are provided utilizing specific monoclonal IgM antibody having an affinity constant not less than about 1.times.10.sup.9 liters per mole. Methods for the preparation and use of such affinity matrices are also given. The detection is rapid, accurate, reproducible, and allows for quantitative recovery of the composition of interest.

Abstract: Method and compositions including monoclonal antibodies to a serogroup-common antigen are provided for the detection and diagnosis of Legionella pneumophila. The monoclonal antibodies recognize a proteinaceous antigen of molecular weight 28,000-29,000 Daltons which is detected in at least serogroups 1 through 8 of Legionella pneumophila and is not detected in other common respiratory pathogens.

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: An improved method for the detection of tetrahydrocannabinol in human urine wherein the pigment melanin is precipitated out of the urine prior to analysis with a solution of nitroferricyanide so that the melanin does not interfere with the analysis. The value attributable to melanin can also be subtracted from the value obtained during the analysis of the urine. The precipitation of melanin prior to analysis or subtraction of the melanin value during analysis greatly reduces the occurrence of false positive test results for persons with dark skin.

Abstract: A method and reagent composition provide for the removal or blocking of serum interferences in liposome immunoassays. A carrier or liposome exhibiting at least one domain of phosphoryl ester groupings different from those of the marker liposome is introduced into the reaction mixture, whereby endogenous interfering species competitively bind to such carrier or liposome rather than to the marker liposome. Also, soluble phosphoryl ester groupings can be introduced into the reaction mixture which react with such endogenous species and further reduce serum interferences.

Abstract: A process for determining qualitatively or quantitatively the presence of Chlamydia Trachomatis or Chlamydia trachomatis derived material in a subject material which process comprises deriving a sample from said subject material Chlamydia trachomatis derived material, contacting said sample with an antibody for a Chlamydia trachomatis derived material bound to a substrate thereby to bind at least a portion of the Chlamydia trachomatis derived material, contacting the bound Chlamydia trachomatis derived material with a conjugate between a substance which will bind selectively to the Chlamydia trachomatis derived material and a catalyst for a reaction system thereby to bind said conjugate to said bound Chlamydia trachomatis derived material, carrying out the reaction system catalysed by said catalyst and determining a product of said reaction system, characterised in that the sample is derived from the subject material by a process including heating the subject material to an elevated temperature and for a peri

Abstract: A method for reducing false positives and to assay background noise in solid phase immunoassays utilizes a matrix coated on a solid support, which matrix contains an effective amount of a noise reduction component and an effective amount of noise balancing component. Optimization of the matrix composition is obtained by measuring parameters for its effectiveness which include sensitivity ratio, noise balance ratio, and signal to noise ratio.

Abstract: An affinity matrix and a method for the detection of low molecular weight compositions such as aflatoxins are provided utilizing specific monoclonal IgM antibody having an affinity constant not less than about 1.times.10.sup.9 liters per mole. Methods for the preparation and use of such affinity matrices are also given. The detection is rapid, accurate, reproducible, and allows for quantitative recovery of the composition of interest.

Abstract: A chemical agent is provided for significantly preventing or blocking non-specific staining or binding of an antibody specific for Terminal deoxynucleotidyl Transferase (TdT) during immunofluorescent or immunoperoxidase assay procedures. These procedures include both immunofluorescent and immunohistochemical staining of samples followed by flow cytometric and/or microscopic analysis, respectively. The invention is practiced by selective use of casein introduced into the assay procedures at an appropriate interval prior to analysis using a labelled or tagged monoclonal antibody specific to a TdT epitope. The casein utilized successfully was obtained from a large variety of sources and includes the use of a non-fat milk product.