Abstract: A novel technique is disclosed for the prevention of false positive reactions in immunological testing which are caused by interference of C.sub.1 and C.sub.1q. The method is based on heating a sample of a body fluid at a temperature of 59.degree.-64.degree. C. in the presence of a particular neutral salt. A method for screening for rheumatoid factor is also disclosed.

Abstract: Methods for determining the presence of a ligand in a sample suspected to contain the ligand are provided, along with apparatus suitable for performing the methods. The methods depend upon a color visualization indicating the ligand's presence or absence in the sample. Preferred methods comprise contacting the sample with colored particles which bear on their surface a receptor specific for the ligand, passing the sample/particle mixture through a filter, and then analyzing the color of the filtrate. The presence of ligand in the sample is established where the color of the filtrate is substantially different from the color of the receptor-bearing particles.

Abstract: The invention relates to a method and reagent for the specific determination of the LDL fraction in the presence of other serum lipoproteins by adding a water soluble polymeric LDL-aggregating agent and a zwitterionic and/or non-ionic detergent. The LDL aggregate is determined in a direct turbidimetric measurement. Preferred LDL-aggregating agents are polyanions having a branched structure with acid groups, particularly branched alkane sulfonic acid groups as side branches. Preferred detergents are those known as "Zwittergent".

Abstract: The invention concerns the use of a composition which is composed of several different antibodies or/and antibody fragments which serves as a reagent to eliminate rheumatoid factor interference in an immunochemical method.

Abstract: A method is provided for preparing lipoprotein (a) from a volume of biological fluid that is substantially free of lipoproteins of another class. The method involves an ultracentrifugation step in which at least one fraction is recovered that contains Lp(a). This material is then reacted with immobilized ligand to remove non-Lp(a) interfering substances from the fraction, the Lp(a) remaining unbound. The non-reacted Lp(a) is subsequently obtained in a form that is suitable for use in the analysis of any of protein concentration, protein isoform determination or cholesterol assays. A method of identifying and measuring an amount of one or more isoforms of Lp(a) is further provided.

Abstract: A method for quantitatively determining cholesterol in high density lipoproteins, in which, prior to the determination of cholesterol by an enzymatic method, a surfactant and a substance which forms a complex with lipoproteins other than high density lipoproteins are added to a sample containing lipoproteins.The method does not require any pretreatments such as centrifugal separation. With a simple operation, cholesterol in HDLs can be measured effectively. Also, this method can be adopted in a variety of automated analyzers, and thus is very useful in the field of clinical assays.

Abstract: In accordance with the present invention, there are provided novel methods and reagents for reducing background binding in antibody preparations having an unwanted affinity for intracellular protein(s). The invention method comprises treating an antibody preparation with permeabilized cells, then separating the antibody preparation from the permeabilized cells. The reagents are useful for reducing the level of background binding in antibody preparations. Also provided are antibody preparations that are substantially free of background binding.

Abstract: The invention is directed to methods and kits for detecting and measuring the presence or absence of perinuclear anti-neutrophil cytoplasmic autoantibody of ulcerative colitis or primary sclerosing cholangitis. The methods and kits of the present invention provide safe and reliable means for diagnosing ulcerative colitis and primary sclerosing cholangitis. The antigens reactive with perinuclear anti-neutrophil cytoplasmic autoantibody of ulcerative colitis and primary sclerosing cholangitis are also provided.

Abstract: This invention provides a process for checking the removal rate of pyrogenic substances, in particular viruses, from organic material. The material to be purified is passed through an ultrafilter or an ultrafiltration unit whose virus-removal rate has already been determined by passing viruses of the Leviviridae family or other comparable small bacteriophages through the filter or filtration unit, the virus titer is determined before and after the filtration operation and the virus removal rate thus calculated. Before or after determining the virus-removal rate, a given pressure is applied to the filter or filtration unit in a gas pressure-hold test, and the decrease in the pressure over a given period is measured. After filtration of the biological material, the rate of virus removal by the filter is checked by repeating the pressure-hold test.

Abstract: Methods and reagents are provided for a novel immunodiagnostic test for the presence of P. aeruginosa in a biological sample. Monoclonal antibodies are employed which bind to an outer membrane protein antigen, which may be exposed by a solubilizing reagent. The antibody binds substantially all strains of P. aeruginosa. No cross-reactivity with other species of Pseudomonas or with other clinically significant gram-negative or gram-positive species is observed. Conjugating the monoclonal antibody of the invention with a fluorescent label provides for a rapid and sensitive direct immunofluorescent test for P. aeruginosa.

Abstract: The invention provides novel labelled boronic acid conjugates of formula ##STR1## (wherein V is a reporter moiety; W.sup.2 is a bond or an organic linker moiety;W.sup.1 is a *SO.sub.2 NR.sup.2, *CONR.sup.2 or *CH.sub.2 N.sup..sym. R.sup.2.sub.2 group bound at the *-marked atom to the phenyl ring;R.sup.1 is hydrogen or an electron withdrawing substituent group; andeach R.sup.2 independently is hydrogen or an optionally hydroxylated and optionally C.sub.1-6 -alkoxylated C.sub.1-6 -alkyl group) and salts thereof, e.g. for use in assays for cis-diols such as glycated blood proteins, having enhanced water-solubility and storage stability.

Abstract: The present invention is drawn to an immunoassay capable of the rapid detection of a variety of test substances that may be present in a test sample. One feature of the invention is that extraction or isolation of the test substance occurs simultaneously with the formation of the primary antigen-test substance complex. The primary antigen-test substance complex is then captured in a solid phase format having a plurality of interstitial spaces which facilitate rapid and efficient detection. The immunoassay of the present invention works over a wide range of environmental conditions and is simple enough to be used in the absence of laboratory facilities.

Abstract: The invention is an improved immunoassay and method for detection of antibody to hepatitis B core antigen (anti-HBc). The improved assay comprises the addition of a reducing agent to decrease the number of false positive reactions in the assay.

Abstract: Disclosed is a process for preparing a C1-esterase inhibitor concentrate, of human plasma origin, comprising 2 separations by chromatography on ion exchanger gels of tentacular type.

Abstract: A chemiluminescent method is provided for the analysis of a target. A peroxidase is first bound as a labelling substance to the target by using a target specific binding reagent. The target so labelled is isolated and then reacted with luminol, hydrogen peroxide and an enhancer in an aqueous solvent. The luminescence of light is detected and measured. The aqueous solvent contains at least one protein selected from the group consisting of skim milk and egg albumin. Preferably, the aqueous solvent also contains a non-ionic surfactant such as a polyoxyethylene ether and/or a sugar alcohol such as mannitol.

Abstract: This invention is directed to a ligand-receptor assay for determining the presence 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 colloidal gold particle, in a fluid sample suspected of containing said target ligand comprising the steps of:a. contacting said fluid sample with said ligand analogue conjugate and said ligand receptor to form a homogeneous reaction mixture, the relative amounts of said ligand analogue conjugate and said ligand receptor being selected such that in the absence of said target ligand and subsequent to substantially equilibrium binding in said reaction mixture, substantially all of said ligand analogue conjugate is bound to said ligand receptor such that no unbound ligand analogue conjugate is detected as a result of the assay method;b.

Abstract: A method for the rapid detection of drug residues in livestock to allow quality certification, involves: taking a bile sample from livestock; cleaning the bile sample by passing the sample under vacuum through a porous silica immunoaffinity column having an immobilized antibody capable of binding the drug to be detected, washing the column free of impurities, and eluting any drug being bound to the column with a suitable solvent; and reacting the cleaned bile sample in a competitive immunometric assay utilizing a labelled antibody.

Abstract: In assays of the type which comprise contacting the sample containing the analyte to be detected with a solid phase surface supporting a ligand capable of binding the analyte, undesired binding to the surface is prevented to a substantial degree by adding to the sample one or more components of the material forming the ligand supporting solid phase surface, which components are in at least partially soluble form and capable of interacting with constituents of the sample medium.

Abstract: The present invention provides an improved method for the preparation of ribonucleic acid (RNA) samples. This method utilizes heat and guanidinium thiocyanate treatment of samples followed by alcohol precipitation and centrifugation to prepare RNA samples with a high degree of sensitivity, reliability, and ease of use. Importantly, the prevent invention provides a method in which RNA samples may be prepared so as to conserve RNA preservation and precipitation reagents and time. The samples so prepared are readily amplifiable and may be used for other purposes as well.

Abstract: The invention features a method of labeling a cell containing an intracytoplasmic target molecule involving (1) permeabilizing the plasma membrane of the cell so that (a) a reagent capable of detectably labeling the intracytoplasmic target molecule can traverse the plasma membrane into the cytoplasm of the cell; and (b) substantially all of the intracytoplasmic target molecule and the DNA of the cell remain in the cell; and (2) contacting the cell with the reagent to label the intracytoplasmic target molecule. The method may further involve detecting the label in the cell, and isolating the cell on the basis of detecting the label in the cell. The invention also includes cells permeabilized using the method of the invention.

Abstract: A method for treating serum samples to remove sialic acid from ligands to expose binding sites to enhance immunological binding, for use in assays and to generate novel anti-ligands is described. The method includes treatment of serum using neuraminidase.

Abstract: A method for separation of a mixture of biological entities into at least three distinct, subpopulations. Different antibodies are provided, with each antibody bound to a solid support in a unique manner such that by a manipulation of the physical or chemical environment, the bonds between the antibodies and the solid supports can be selectively broken. The mixed population of cells is incubated with the antibodies. The cells are magnetically separated from a test medium and collected in a monolayer upon a collection surface. Then by manipulation of the physicochemical environment, specific linkages can be broken and desired cell subpopulations released from the collection surface. This method has medically significant diagnostic and therapeutic applications, as entire cell types can be separated from non-malignant medically vital cell types. Cancer can be diagnosed, staged, and monitored. Genetic analysis from maternal blood, CVS, or amniocentesis samples is possible.

Abstract: A method of dispensing wash solution to separate free from bound labels in a slide immunorate assay. The method comprises dispensing wash first as separate drops spaced to allow complete absorption prior to the next drop, followed by a time at which the rate of dispensed wash exceeds the rate of fluid uptake of the slide, to form a continuous stream. The first phase of this wash method provides a more complete separation of bound from free under the dispense tip than occurs if only a continuous stream is used throughout.

Abstract: A method of determining a hapten which comprises: (1) contacting the sample which contains or may contain the hapten with a first binding partner which binds the hapten; (2) separating the hapten bound to the first binding partner from material which is not bound by the first binding partner; (3) contacting the hapten bound to the first binding partner with a second binding partner which binds the hapten; and (4) assaying the hapten bound to a binding partner as is described. Kits are also described.

Abstract: An assay and sample mixture for the enumeration of fluorescently stained target components of a whole blood sample by an imaging instrument. The sample preparation method ensures that the amount of target components per unit of volume of the whole blood sample is preserved by elimination of certain non-quantitative preparation steps while producing an even hematocrit layer within a scan capillary. Typical target components include white blood cells that express certain surface antigens, such as CD-4 and CD-8 proteins. To inhibit aggregation of the red blood cells, a reagent is added to an aliquot of whole blood sample. The aliquot of whole blood is mixed and with a preselected amount of a fluorescent dye and ligand complex which tags the target components.

Abstract: A method for reducing or eliminating tyramine interference from amphetamine and methamphetamine immunoassays, comprising treating the sample with aqueous tyramine oxidase for a time and at a temperature and pH sufficient to deaminate any tyramine present in the sample, is provided.

Abstract: A method and kit for extracting fungus from a plant. An extraction solution is combined with tissue from a plant and the combination is agitated, preferably by shaking, to extract a detectable amount of the fungus from the plant. The extraction solution is a solution containing a dilute acid and a detergent. The extract can then be neutralized without degradation of the fungus and subjected to analysis by immunoassay to detect the presence of pathogenic fungi. The method is particularly useful for the detection of Pyricularia oryzae on rice plants.

Abstract: A system for determining the concentration of fructosamine in sera which consists of a first reagent in which a tetrazolium salt which reduces all reactive substances in sera including fructosamine and a second reagent which is responsive to all reactive substance in sera other than fructosamine. The difference in color change as between the two allows the determination of concentration of fructosamine.

Abstract: A method for detecting at least one virulence-associated factor (VAF), e.g., a bacterial toxin, in a sample is described. The sample suspected of containing the VAF-producing bacteria is contacted with a VAF releasing solution under conditions which release VAF from the bacteria. The released VAF subsequently is immunochemically detected. The preferred method is a membrane-based enzyme linked immunosorbent assay for immunochemically detecting the well-characterized Shiga family toxins including SLT I and SLT II. Also described is the VAF releasing solution and a kit containing the reagents for conducting the described methods.

Abstract: The present invention provides ligand/anti-ligand assays for detecting and/or measuring adherent proteins, including lipophilic serum or plasma proteins, such as serum amyloid A (SAA) and apolipoprotein Al (apoAl); cytokines such as IL-1 beta, IL-6, and TNF alpha; pentraxins, such as CRP; and globular serum or plasma proteins such as albumin.

Abstract: The present invention relates to a method employing at least one luminescent tracer compound and a luminescent compound used as an internal reference, which, when exposed to the same excitation wavelength, are capable of emitting at difference wavelengths, .lambda..sub.2 and .lambda..sub.1 respectively, either by direct luminescence or by the induction of a luminescent emission, and correcting the measurement of the luminescence emitted by the tracer compound at wavelength .lambda..sub.2 on the basis of the measurement of the luminescence emitted by the reference compound at wavelength .lambda.1.

Abstract: An improved one-step immunochromatographic assay which involves the binding of a predetermined amount of analyte to an antibody, enabling the control of the assay sensitivity, is disclosed. The system is especially useful as a controlled sensitivity fecal occult blood assay. Antibodies to a desired analyte, present at a predetermined concentration, are deposited on the sample pad of the reaction unit. The antibody binds analyte present in the sample, up to a threshold amount. Analyte which is present in the sample at a level above the threshold amount proceeds unbound through the sample pad and onto a membrane, where it reacts with an antibody-coated latex and a second, immobilized antibody to generate a positive signal.

Abstract: The invention relates to immunoassay reagents that are both sensitive and specific and which require no sample pretreatment. The invention reagents are particularly useful for assaying digoxin concentrations in patient sera. More particularly, the invention relates to methods and kits comprising (A) an immunoreactant immobilized on a support; and, (B) a buffer agent comprising (i) a buffering agent, (ii) sodium chloride, (iii) choline chloride, (iv) a polysaccharide, (v) fatty-acid-free serum albumin, and (vi) a non-specific reaction suppressor of the formula: ##STR1## wherein X is --NH--(CO)--NH--, --NH--(CS)--NH--, or --N.dbd.C.dbd.N--, R.sub.1 and R.sub.2, which may be the same or different, are C.sub.1 -C.sub.5 linear or branched alkyl groups, or R.sub.1 and R.sub.2, together with nitrogen, is ##STR2## or the metho-p-toluenesulfonate salt thereof, Y, which may be the same or different, is any of H, OH and halogen,R.sub.3 is --NR.sub.1 R.sub.2, --NH.sub.

Abstract: An improved immunoassay method and kit have been developed that include a sample pretreatment method and kit employing an alkylating agent that modifies antibodies in the sample to render the antibodies incapable of interfering with analyte detection. Prior to performing the immunoassay, the alkylating agent is inactivated so that it does not modify antibody reagents used in the immunoassay.

Abstract: This invention pertains to methods to detect a compound in the presence of a homolog that is immunologically related to the analyte. The invention is particularly suited for the detection of homocysteine in the presence of cysteine. The methods of this invention involve chemically modifying both the analyte and the homolog to increase their immunogenicity and facilitate antibody recognition. More importantly, this modification is done to make these compounds immunologically distinct. Antibodies to the immunologically distinct compounds are then prepared. An assay protocol comprises chemically modifying the analyte and homolog and then immunochemically detecting the modified analyte by means of the aforementioned antibodies.

Abstract: The present invention is directed to a multi-layer test device and method for analyzing the concentration of fructosamine in a liquid sample. The multi-layer test device has a buffer layer containing a buffer having a pH value of at least 9 which is either superposed above or juxtaposed to an indicator layer containing an indicator capable of being reduced by fructosamine. Supporting the buffer layer, the indicator layer, and any additional layers in the multi-layer device is at least one support member which optionally has a detection aperture for analyzing the concentration of fructosamine on the indicator layer. An additional support member having a sample aperture can be used. Where two support members are used the multi-layers are sandwiched between the first support member having a sample aperture and the second support member optionally having a detection aperture.

Abstract: A method for the direct analysis of analyte indicative of marijuana exposure found in keratinized structures, e.g., hair, fingernails and toenails, which comprises preparing a mixture containing dithiothreitol or dithioerythritol, a protease suitable for the digestion of the keratin structure and a sample of the keratin structure; permitting the enzyme to at least substantially digest the sample of keratin structure to form a digest solution, followed by mixing the digest solution with a suspension of an ion exchange resin to remove an interfering, cross reacting substance naturally found in hair and finally subjecting the digest solution to analysis to determine the identity and amount of marijuana analyte in the keratin structure sample. To accelerate the method, cupric sulfate may be added to the mixture after degradation of the keratin sample in order to deactivate the activator. The enzyme may be a protease with papain, chymopapain, and proteinase K being preferred for use in the invention.

Abstract: The invention relates to a latex agglutination method for the detection or determination of one partner of an antigen-antibody reaction, wherein, in order to suppress non-specific reactions, to, for example, Clq and rheumatoid factors the immunochemical reaction takes place in the presence of an immune complex which does not contain any antibody or antigen that is specific for one of the partners.

Abstract: The present invention includes novel digoxin assays employing a capture reagent, involving a first binding member conjugated to a polymeric anion substance, and a solid phase material containing a reaction site comprising a polymeric cation substance having a nitrogen content of at least about two percent. A test sample suspected of containing the analyte of interest may be contacted with the capture reagent to form a charged capture reagent/analyte complex. The complex is then contacted to the oppositely charged solid phase to attract, attach, and immobilize the capture reagent/analyte complex.

Abstract: The present invention provides a test strip for detecting, in a sample from a human subject, the presence of an antigenic substance which comprises a solid support, an antibody directed against the antigenic substance bound to a first discrete area on the solid support, an anti-human antibody bound to a second discrete area on the solid support as a positive control, and an antibody directed against an antigen which does not naturally occur in human subjects bound to a third discrete area on the solid support as a negative control. The present invention also provides a test strip for detecting, in a sample from a human subject, the presence of an antibody which comprises a solid support, an antigenic substance bound to a first discrete area on the solid support, an anti-human antibody bound to a second discrete area on the solid support as a positive control, and a negative control bound to a third discrete area on the solid support.

Abstract: A new enzymatic rate method is disclosed for the analysis of Vitamin C using ascorbate oxidase. Total Vitamin C can be measured in a single analysis, in a procedure amenable to automation. Any dehydroascorbic acid (DHAA) in the sample is reduced to ascorbic acid. Then a coupling agent such as o-phenylenediamine (OPDA) is added to the sample, and any nonspecific reactions with, or spectrometric interferences from, other components of the sample are measured, to be blanked out from the final measurement. Then ascorbate oxidase is added, oxidizing ascorbic acid to DHAA; the DHAA then reacts with the OPDA already present from the prior step, and the quinoxaline derivative product may be measured spectrometrically, e.g., by absorbance at 350 nm.

Abstract: The invention relates to an agent and process for treating body fluids in the immunological determination of neopterin using a specific antibody against neopterin and a detection system. The agent is characterized in that it contains an oxidizing agent.

Abstract: Improved methods for the GC/MS analysis of sulfhydryl amino acids and methylmalonic acids in samples of body fluids are provided. Additionally a method for combined assay of sulfhydryl amino acids particularly total homocysteine and combined creatine/creatinine levels in samples of body fluids provided. The information provided by the methods described is useful in the detection of the presence of cobalamin or folate deficiencies in individuals and in distinguishing between the two deficiencies.

Abstract: This invention relates to an enzyme assay for quantitative analysis of biochemical substances using NAD(P)-NAD(P)H system and utilizing hydrogen peroxide, in which isocitric acid, metal ions and isocitrate dehydrogenase are previously added to a test sample, thereby consuming the endogenous substances that interfere the analysis, and at the same time regenerating NAD(P)H reduced.The isocitrate dehydrogenase is then inactivated by addition of a chelating agent, an enzyme or substrate that generates hydrogen peroxide as reaction product is added simultaneously or thereafter, and the amount of hydrogen peroxide thus formed is measured.Biochemical substances that generate hydrogen peroxide as reaction product can be correctly analyzed by this method with no adverse effect of endogenous substances because these interfering substances have been removed prior to measurement.

Abstract: A method is described for the use of monoclonal antibodies in a sensitive immunoassay for halogenated dioxins and dibenzofurans in industrial samples which contain impurities. Appropriate sample preparation and selective enzyme amplification of the immunoassay sensitivity permits detection of dioxin contaminants in industrial or environmental samples at concentrations in the range of a few parts per trillion.

Abstract: A reagent for measuring immature leukocytes which comprises: (1) a polyoxyethylene-based nonionic surfactant having the general formula (I) in a sufficient amount capable of fixing cytoplasms and cell membranes of immature leukocytes:R.sub.1 --R.sub.2 --(CH.sub.2 CH.sub.2 O ).sub.n --H (I)where R.sub.1 is an alkyl, alkenyl or alkynyl group having 10 to 25 carbon atoms; R.sub.2 is --O--, --(C.sub.6 H.sub.4)--O-- or --COO--; and n is an integer of 10 to 40, (2) a solubilizing agent in a sufficient amount capable of damaging cell membranes of blood cells other than immature leukocytes and shrinking them, (3) an amino acid in a sufficient amount capable of stabilizing cytoplasm and cell membrane of immature leukocytes, and (4) an aqueous medium, which adjusts pH value in the range of 5.0 to 9.0, osmolarity in the range of 150 to 600 mOsm/kg and electric conductivity in the range of 6.0 to 9.0 mS/cm, respectively.

Abstract: A method for measuring the number of living microorganisms in a specimen which comprises entrapping the microorganisms on a hydrophobic filter after the dyeing thereof, or alternatively dyeing the microorganisms after entrapping them on the hydrophobic filter, removing excessive coloring matter by washing, and then determining the number of the microorganisms by the degree of coloration thereof. A kit for measuring the number of living microorganisms which comprises a hydrophobic filter, a syringe to which the filter is fittable, a coloring matter solution, a cleaning solution, and a color reference table. The present invention enables the rapid and convenient measurement of the number of living microorganisms in the specimen without use of special equipment. In accordance with the present invention, the measurement is usually completed within ten minutes.

Abstract: A method is provided, in one embodiment, for the determination of an analyte in a biological fluid sample in the presence of a substance interfering with an assay for the analyte. This embodiment is implemented by using antibodies to cause the selective immunoreaction of at least one of the analyte or the interfering substance and then conducting an assay for the analyte in at least one of the immunoreactants or the non-reactants. Another embodiment provides a disposable reaction device to implement the method. The invention is applicable to the detection of a wide variety of analytes, including cholesterol in a targeted lipoprotein class in the presence of cholesterol in another class; to targeted isozymes of enzymes such as creatine kinase, lactate dehydrogenase, amylase, and alkaline or acid phosphatases in the presence of other isozymes; as well as to targeted immunoglobulins in the presence of non-targeted immunoglobulins.

Abstract: This invention relates to an improved assay device and assay for detecting or quantitating the presence or absence of a substance in a sample. The device has multiple layers comprising a permeable layer (a) having a capture reagent attached to less than the entire membrane, a selectively permeable layer (b) which does not allow assay reagents to pass through (b) and an absorbent layer (c). Layer (b) is in communication with layers (a) and (c). Layer (b) has at least one hole extending therethrough and the hole or holes are directly below the capture reagent in layer (a). The area of the hole or the combined area of the holes is less than the area covered by the capture reagent. This invention also relates to a method of reducing background color development in an absorbent layer of an assay device.

Abstract: The present invention provides monoclonal antibodies directed against specific domains of fibronectin and vitronectin. These monoclonals may be used in the production of the biomaterial and devices for use in in vitro cell culture. The present invention also provides an efficient method for extracting vitronectin from bovine serum or plasma using monoclonal antibodies and methods for analyzing biological samples for the presence of adhesive glycoproteins or fragments thereof.