Abstract: The present invention provides a method and device for detecting the presence of binding ligands, especially blood group antigens or antibodies thereto, which utilize a matrix of substantially noncompressable microparticles, which matrix provides superior performance in allowing movement of nonagglutinated reactants, especially red blood cells, while constraining, preferably in a so-called "band formation" agglutinated reactants, especially red blood cells.

Abstract: The present invention provides labeled nucleotide probes and a procedure for synthesis of the labeled nucleotide probe by a coupling or joinder of two components of the probe, namely a target recognition sequence moiety and a signal generating moiety, through the use of a bridging complement that holds the two moieties in such a position as to allow formation of a sugar-phosphate chemical linkage between the 3' end of one moiety and the 5' end of the other moiety.

Abstract: The probes of the invention are made up of a target recognition moiety and a signal generation moiety. In the first step of the preparatory method of the invention, the 5' or 3' terminus or both of the target recognition moiety is chemically altered to incorporate a reactive functionality which will allow chemical linkage of this target recognition moiety with one or both termini of the signal generation moiety of the probe. Suitable functionalities vary widely, but may, in general be described as those that allow chemical attachment of the two moieties either at the 5' or 3' end of the target recognition moiety. The two moieties should not detach from each other upon hybridization of the target moiety to the target analyte. Thus, when the probe is hybridized to target analyte, it will then carry with it, signal moiety, to label this complex, which label is then later detected.

Abstract: A method and test kit useful in a wide variety of immunoassay systems. A method of producing metal sol reagents containing metal sol particles of a preselected size is provided. A metal containing solution is reduced under optimized pH conditions to produce metal sol particles of a preselected size, the particles are coated with a coupling compound and then bound with at least one selected immunochemically reactive component. Particles having different immunochemical specificities are also mixed to produce reagents having multiple selected immunochemical specificities.

Abstract: A vessel for conducting blood cell agglutination assays is disclosed. A barrier retains reactants in an upper chamber during incubation, then, in response to a force, permits reagents to enter a lower chamber containing a matrix for separating agglutination.

Abstract: Nucleic acid probes that detect Salmonella human pathogens are generated from the nucleotide sequences of a gene encoding a virulence factor involved in the pathogenesis of Salmonella, especially the Type 1 fimbriae protein. Preferred probe lengths are about 20 to about 100 nucleotide bases. The probes are highly specific and sensitive for detecting Salmonella organisms pathogenic to humans and are thus clinically useful in the detection of infection in diarrhea specimens. They also may be used in the detection of food-borne Salmonella, the causative agent of most salmonellosis in humans.

Abstract: A cell fixative composition for fixing the internal components of a cell without disrupting the cell surface components is disclosed. The composition contains a compound for preserving intracellular morphology, a compound for fixing internal components of the cell, a compound which facilitates transportation of components across the cellular membrane, and a compound for increasing permeability of cell membranes. Methods for analyzing cells which have been fixed using the composition are also disclosed.

Abstract: A polypeptide linked to a solid matrix useful as a solid support of a diagnostic kit is disclosed. The polypeptide has the formula: X-Glu-Thr-Gly-Gln-Glu-Thr-Ala-Tyr-Phe-B-Leu-Lys-Leu-Ala-Gly-Arg-Trp-Pro-Va l-Lys-Z, wherein B is Ile or Leu, X is a chain of from 1 to 20 amino acid residues or an amino-terminal group and Z is a chain of from 1 to 20 amino acid residues or a carboxy-terminal group. The polypeptide immunologically mimics HIV endonuclease.

Abstract: The probes of the invention are made up of a target recognition moiety and a signal generation moiety. In the first step of the preparatory method of the invention, the 5' or 3' terminus or both of the target recognition moiety is chemically altered to incorporate a reactive functionality which will allow chemical linkage of this target recognition moiety with one or both termini of the signal generation moiety of the probe. Suitable functionalities vary widely, but may, in general be described as those that allow chemical attachment of the two moieties either at the 5' or 3' end of the target recognition moiety. The two moieties should not detach from each other upon hybridization of the target moiety to the target analyte. Thus, when the probe is hybridized to target analyte, it will then carry with it, signal moiety, to label this complex, which label is then later detected.

Abstract: Methods of immobilizing nucleic acid on a solid surface for us in nucleic acid hybridization assays is disclosed. The methods of the invention comprise reacting a modified nucleic acid strand comprising a variable portion and an anchor portion wherein the variable portion comprises a nucleotide sequence having a selected base sequence and the anchor portion comprises at least one nucleotide base modified with a primary amine function or nucleotide base equivalent having a primary amine function and reacting the modified nucleic acid strand with a free aldehyde group of the solid surface in the presence of a reducing agent to form complexes of the modified nucleic acid strand and at least a portion of the free aldehyde groups on the solid surface.

Abstract: A stabilized proteolytic solution has been developed which can be used to treat selected cells, especially red blood cells. A preferred stabilized solution of the invention comprises about 0.1% to about 0.3% ficin in a citrate-buffered saline solution containing mannitol, L-cysteine, dithiothrietol in an active concentration of less than about 10 mM, and EDTA. A kit for qualitatively identifying unexpected blood group antibodies comprising a series of untreated and ficin-treated red blood cells, a stabilized ficin reagent, a red blood cell diluent and an enzyme control is also provided.

Abstract: A method of determining levels of extrinsic and intrinsic clotting factors and protein C based upon the reaction rate of the observed clot formation and the first derivative of the reaction rate of observed clot formation is provided. In accordance with the teachings of the invention, the reaction rate of the observed clot formation in a prothrombin time test or an activated partial thromboplastin time assay is determined for both test and normal plasma samples and the reaction rates compared. In another embodiment, the first derivative of the reaction rate of the observed clot formation is determined and the results compared.

Abstract: The invention discloses nucleic acid probes specific for Neisseria gonorrhoea useful in diagnostic methods to detect the presence of N. gonorrhoea in biological specimens.

Abstract: The invention discloses nucleic acid probes specific for Neisseria gonorrhoea useful in diagnostic methods to detect the presence of N. gonorrhoea in biological specimens.

Abstract: The invention discloses nucleic acid probes specific for Neisseria gonorrhoea useful in diagnostic methods to detect the presence of N. gonorrhoea in biological specimens.

Abstract: A new immunoassay system is provided for the detection of ligands or ligand binding partners in solution in a heterogeneous format. The invention relies upon the detection of back scattered light from an evanescent wave disturbed by the presence of a colloidal gold label brought to the interface by an immunological reaction. The evanescent wave existing at the interface in turn is the result of a totally internally reflected incident light wave. Placement of the detector at a back angle above the critical angle insures a superior signal-to-noise ratio.

Abstract: An assay device is provided which includes a support, generally planar and elongated in shape, upon which a biological binding reaction may take place. This assay support includes in its broadest aspect, three sections, a sample receiving well section at one end and a gripping section at the opposite end, with a connecting section therebetween. The sample receiving well section includes at least two spaced-apart receiving wells, generally at the end of the assay support, for the addition of binding reactants. Each of the wells has an open end on a first face of the support, a concave inner surface extending concavely into the support, and a convex outer surface which projects convexly from an opposed face of the support. These wells may serve as a depository to contain aliquots of binding reagents, as well as a sample under analysis, the sample under analysis possibly containing a substance that will bind to the binding reagents.

Abstract: A new immunoassay system is provided for the detection of ligands or ligand binding partners in solution in a heterogeneous format. The invention relies upon the detection of back scattered light from an evanescent wave disturbed by the presence of a colloidal gold label brought to the interface by an immunological reaction. The evanescent wave existing at the interface in turn is the result of a totally internally reflected incident light wave. Placement of the detector at a back angle above the critical angle insures a superior signal-to-noise ratio. Apparatus and methods for scanning, detecting and manipulating light including a scattered total internal reflectance immunoassay system are provided.

Abstract: Methods for attaching one component of a ligand-anti-ligand pair onto a solid phase surface. The component may be attached to a photoactivatable cross-linker capable of coupling the component to a colloidal medium coating the surface or alternatively, the component may be coupled to a bead and held in place against the surface by an overlay of the colloidal media having voids and spaces smaller than the diameter of the particle but large enough to permit diffusion of the other of the ligand-anti-ligand pair to be detected.