Abstract: An accurate, stable, liquid lipoprotein control composition is provided. The control composition of the present invention preferably comprises lipoprotein, suffactant and a divalent cation. The control may further comprise a chelating agent. It has been surprisingly found that when suffactant and a divalent cation are added to lipoprotein, it performs like native lipoprotein in human serum, i.e. not aggregated or subject to matrix effects. In addition, the control composition of the present invention is stable for up to about 5 months at room temperature (about 22.degree. C.) and up to about 12 months when refrigerated (about 2.degree. C. to about 10.degree. C.). Methods of making and using the control composition are also provided.

Abstract: In order to determine lupus anticoagulant (LA) antibodies in blood, plasma or tissue samples by means of the inhibitory effect of these antibodies on the neutralizing effect of protein C on the blood coagulation system, a defined amount of activated protein C is added to the sample, after incubation the remaining amount of a physiological substrate of protein C or protein S activity in the sample is determined according to known methods and the amount of LA antibodies present is calculated by comparison with a standard containing no LA antibodies. The method according to the present invention can be used to diagnose a predisposition to thrombotic events or disease-dependent risk of thrombosis as well as to monitor a therapy.

Abstract: The present invention relates to the rapid detection of Group A streptococci in clinical specimens, through the enzymatic digestion by a semi-purified Group C streptococcal phage associated lysin enzyme and the identification of the released antigens, through the reaction of a labelled ligand and its respective antigen or receptor. The labelled ligand can be included during the digestion of the bacteria, enabling the total assay time to be less than five minutes. The lysin enzyme is stabilized and can be lyophilized for in situ reconstitution.

Abstract: An analytical test device useful for example in pregnancy testing, includes a hollow casing (500) constructed of moisture-impervious solid material, such as plastics materials, containing a dry porous carrier (510) which communicates indirectly with the exterior of the casing via a bibulous sample receiving member (506) which protrudes from the casing such that a liquid test sample can be applied to the receiving member and permeate therefrom to the porous carrier, the carrier containing in a first zone a labelled specific binding reagent is freely mobile within the porous carrier when in the moist state, wherein the mobility is facilitated by a material comprising sugar, in a amount effective to reduce interaction between the test strip and the labelled reagent, and in a second zone spatially distinct from the first zone unlabeled specific binding reagent for the same analyte which unlabelled reagent is permanently immobilized on the carrier material and is therefore not mobile in the moist state, the two zo

Abstract: A method and device for detecting fetal membrane rupture by detecting only that insulin-like growth-factor-binding protein 1 (IGFBP-1) which is free of insulin-like growth factors 1 and 2 (IGF-1 and IGF-2) are disclosed. The method is based on the fact that the concentration of free IGFBP-1 in the blood serum is about 10 times lower than that of the IGFBP-1 bound to IGF-1 and IGF-2, while in the amniotic liquid which is contained in the amnion has more than 1000 times the concentration of free IGFBP-1 than the blood serum. Therefore, when even a small amount of amniotic liquid is contained in the vaginal secretion sample, this is clear evidence of the rupture of the fetal membrane having taken place. The method and the device make it possible to diagnose fetal membrane rupture with an extremely high accuracy. Because of the low concentration of the IGFBP-1 in the blood, the admixture of the blood serum to the sample does not affect the results of the test.

Abstract: A method of separating a first class of lipoprotein in a sample from a second class of lipoprotein in the sample including: precipitating the second class of lipoprotein; contacting the sample with a magnetically responsive particle; and placing the sample in a magnetic field until the magnetically responsive particle has sedimented, thereby causing the precipitated second class of lipoproteins to sediment, leaving the first class of lipoproteins in the supernatant of the sample.

Abstract: A chromatographic test strip comprising a solid support having at least a first portion and a second portion with said portions being in the same plane so as to permit capillary flow communication with each other. The sample is added to the first portion. The first portion also may comprise a tracer portion having a tracer movably supported therein. The tracer consists of a visible particulate marker. In the second portion, a binder is immobilized. The test strip is useful in a variety of immunoassays.

Abstract: Method for the quantitative determination of plasmin-.alpha.2-antiplasmin complexes, using a specific monoclonal antibody directed against the neoantigene in the plasmin-.alpha.2-antiplasmin complex, and use of such a method of determining PAP-complexes in plasma and serum to assess changes in the fibrinolytic potential.

Abstract: Drug-dependent antibodies that bind to granulocytes, erythrocytes, platelets or membrane proteins derived from these cells, in the presence of a drug, but not in its absence, can be detected using a sensitive assay. Detection of the drug-dependent antibodies permits diagnosis of cytopenia mediated by the drug.

Abstract: An initial rate photometric immunoassay method useful for detecting and quantifying analytes in various physiological fluids is disclosed. The method is carried out by combining in a liquid medium an undiluted sample of analyte-containing physiological fluid, such as serum, and an excess of an anti-analyte antibody. A substantially constant initial rate of increase of the liquid medium's turbidity, due to the resulting immunoprecipitation reaction, is measured in real time and compared to a calibration curve prepared from known analyte concentrations to detect and quantify the analyte. Detection and quantification of numerous analytes including, haptens, drugs and proteins, in a wide variety of physiological fluids can be rapidly carried out by the present method.

Abstract: Human red blood cells with antigenic determinants recognized by unexpected alloantibodies are mixed with serum from the potential recipient. Following incubation, multivalent monoclonal IgM antibodies specific to the antigenic determinant present on the test red blood cells are added. If the recipient's serum is negative for an unexpected antibody which would bind to the antigens present on the test red blood cells, then the multivalent antibody will agglutinate the red cells. Conversely, if an unexpected antibody specific to those determinants is present in the recipient's serum, hemagglutination will be inhibited.

Abstract: The analytical dipstick of the present invention facilitates analyte testing with reduced liquid reagent volumes and provides improved mixing. The dipstick includes an elongated member having a fluid displacing member at one end thereof and a ligand attached to a portion of the elongated member in a region adjacent to the displacing member. The displacing member has a configuration that substantially conforms with the inner side wall of an analytical well in which the dipstick is placed to displace fluid therein. When the displacing member is substantially centered at the bottom of the well, the portion of the dipstick supporting the ligand preferably is spaced from the inner side wall by a distance of at least about twice that between the displacing member and the inner side wall, measured along a line passing through the greatest lateral dimension of the displacing member.

Abstract: An IgM class monoclonal antibody which specifically reacts with mucus glycoproteins produced by human gastric gland-type mucous cells is provided. By performing immunohistochemical staining using a labeled derivative of the monoclonal antibody, human gastric gland-type mucous cells as well as mucus secreted by these cells can be specifically stained. The monoclonal antibody can also be used for the analysis of gastric gland-type mucous cell-derived mucus glycoproteins in human body fluids as well as for the examination or diagnosis of cancer.

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 monoclonal antibody having high affinity to human cardiac myoglobin, which has undergone a conformational change resulting from the binding of the molecule to another molecule is described. This monoclonal antibody can be used in a rapid format double antibody immunoassay system to identify blood, serum or plasma levels of cardiac myoglobin. Such an immunoassay system can be used for diagnosing and quantifying myocardial necrosis and infarction.

Abstract: The subject invention pertains to a method of binding proteins and double-stranded DNA to the same membrane matrix. The DNA bound to the membrane matrix remains in double-stranded form. The subject invention further concerns an assay procedure for detecting antibodies, such as autoimmune antibodies, in a biological sample that are immunoreactive with the proteins and double-stranded DNA attached to a membrane matrix. The subject invention provides a single assay system that allows for the determination of antinuclear antibody specificities which can be used to aid in the diagnosis and monitoring of autoimmune diseases.

Abstract: A method for reducing interferent bias such as hemoglobin bias in immunoassays using dried slide test elements featuring peroxidase and leuco dye as the labeling mechanism.

Abstract: The invention relates to a method for determining analytes, in which a sample of a biological material which possibly contains this analyte is incubated with at least one binding partner which is specific for the analyte and which is immobilized on a particulate carrier material, and the change in turbidity brought about by the analyte is determined.

Abstract: An apparatus is provided for use in assays for the detection of a bindable target substance in a liquid sample. The apparatus comprises an elongate reaction membrane strip which is porous and liquid-permeable, the upper surface of the membrane strip having receptors thereon capable of binding to the target substance; an absorbent material located adjacent to the lower surface of the reaction membrane strip; and a container means for the reaction membrane strip and absorbent material, including a top wall defining a fluid port in the form of an elongate slot adjacent the membrane strip and including a fluid seal means disposed at the periphery of the fluid port defining a seal between the container top wall and reaction membrane strip. In one embodiment, the receptors on the membrane strip correspond to Western blot proteins. An assay for the detection of bindable target antibody in a liquid sample employing the apparatus is also described.

Abstract: An immunoassay element for quantitatively analyzing a ligand by determining the change in enzymatic activity caused by a reaction between the ligand, a linked product of the ligand and a high molecular weight compound and an enzyme-labelled antibody. The immunoassay element comprises a substrate layer containing a non-diffusible substrate which forms a diffusible material in the presence of the enzyme, and a reagent layer containing a fragmenting enzyme for further fragmenting the non-difussible material. Also provided is a process for quantitatively analyzing a ligand contained in a sample by the use of the immunoassay element.