Abstract: A screening device for performing an immunoassay test to detect the presence of a compound in a body fluid. The device includes a holder for removably receiving a membrane to which the fluid has been applied. A light is directed to the membrane. A photodetector measures the concentration of the light reflected back from the membrane. Specifically, the concentrations of reflected light from a control zone and a test zone are measured. Signals representative of the measured light concentrations are applied to a processor. If a specified concentration of predetermined light from a control zone on the membrane is detected, the processor considers the test to be successful. In the test is successful, the processor, based upon the measured concentration of reflected light from the test zone, generates data representative of the presence of the compound.

Abstract: The present invention provides a method for reducing undesirable light emission from a sample using at least one photon producing agent and at least one photon reducing agent (e.g. dye-based photon reducing agents). The present invention further provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one collisional quencher. The present invention also provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one quencher, such as an electronic quencher. The present invention also provides a system and method of screening test chemicals in fluorescent assays using photon reducing agents. The present invention also provides compositions, pharmaceutical compositions, and kits for practicing these methods.

Abstract: To measure or exert optically-induced forces on at least one particle in the focus of an optical cage, the following steps are taken: a) the focus is positioned in a microelectrode arrangement with a three-dimensional electrical field that has a field gradient which forms an electrical capture area, and the focus is at a distance from the capture are and b) the amplitude of the electrical field, the light power of the light beam forming the optical cage, and/or the distance of the capture area from the focus are varied to detect which varied field property moves the particle from the focus to the capture area or vice versa, or at least to temporarily move the particle into the capture area.

Abstract: The invention relates to a method for determining the conformational state of a protein, comprising the steps of: a) providing a first binding partner which is capable of binding to the protein in a manner dependent on the conformational state of the protein and which generates a signal in a manner dependent on the binding of the first binding partner to the protein; and b) contacting the protein with the first binding partner and determining the conformational state of the protein by assessing the labelling of the protein by the binding of the first binding partner.

Abstract: The present invention provides a method for determining expression levels of one or a multiplicity of target proteins in a tissue or cell sample.

Abstract: Immunoassay methods and apparatus are provided which utilize flow cytometry, coated latex microspheres, and fluorochrome labeled antibodies, to simultaneously detect the presence and amount of one or more analytes in a sample. Beads of several different sizes, colors or shapes, each bead are coated with a different analyte, for the simultaneous detection of one or more analytes and of cell components. The invention is also directed to platelet Ig positive control reagents and assays which provide for the setting of the fluorescence positive region for each patient. The platelet control is sized to fit between the platelets and red cells and thus making it ideal as a true biological control.

Abstract: The invention relates to a method of evaluating the immunological status of a subject comprising the steps of 1) determining the content of an antibody in a liquid sample from the subject using an immunoassay, wherein the reaction between the antibody of the sample and a ligand in the form of an antigen, an antibody or a hapten, the ligand being directed to the Fab region of the sample antibody, is carried out in the presence of other constituents of the sample to obtain a measurement 1, 2) determining the content of an antibody in the liquid sample using an immunoassay, wherein the reaction between the antibody of the sample and a ligand in the form of an antigen, an antibody or a hapten, the ligand being directed to the Fab region of the sample antibody, is carried out in the absence of other constituents of the sample to obtain a measurement 2, and 3) interrelating measurements 1 and 2 to express the interference and using the interference as a parameter for evaluating the immunological status of the subje

Abstract: Immunoassay methods and apparatus are provided which utilize flow cytometry, coated latex microspheres, and fluorochrome labeled antibodies, to simultaneously detect the presence and amount of one or more analytes in a sample. By combining FALS and fluorescence, it is practical to use beads of several different sizes, colors or shapes, each bead coated with a different analyte, for the simultaneous detection of one or more analytes and of cell components such as platelets in a sample.

Abstract: Methods and reagents for rapid purification and/or identification of particles in a liquid sample are described. The technique uses centrifugation to concentrate particles against a slanted surface having an agent specifically binding to the particles. This method is applicable for the rapid identification of viruses and other difficult or impossible to culture microorganisms without replication or amplification of the microorganism.

Abstract: A device for analyzing immunoassays with a liquid assay medium includes a vessel for holding the assay medium. The vessel has a base comprised of a solid body having a first side wall and a top surface forming a boundary surface of the solid body. First reaction agents are dissolved in the assay medium in the vessel and are labeled with a luminophore or different luminophores and second reaction agents are bonded to the boundary surface within a boundary layer of the assay medium. A transmitter for emitting light rays is arranged so that the light rays are coupled into the base of the vessel via the first side wall and conducted at the total reflection angle to the boundary surface so that luminophore-labeled first reaction agents that are bonded to the second reaction agents are optically excited by at least some of the light rays and emit fluorescent and/or phosphorescent rays. A receiver is positioned for quantitatively detecting the fluorescent rays and/or phosphorescent rays.

Abstract: The amount of platelet surface proteins in a sample may be measured by collecting a sample containing platelets into a collection tube containing a platelet stabilizing composition, labeling the platelet surface protein and detecting by cytometry.

Abstract: A liquid composition comprising a colloidal suspension of a biomolecule-binding matrix material (preferably nitrocellulose) dispersed in a liquid, with particles of the matrix material being of a defined particle size, and replicate copies of a biomolecule, e.g., protein or nucleic acid probes, which are distributed, preferably uniformly, throughout the colloidal suspension and are bound to the matrix material particles, is disclosed. The liquid composition of the invention can be used directly for sample analysis or preparation of biomolecules, or aliquots of the composition can be spotted onto a support to form a microporous matrix system or microarray for analysis or preparation of biomolecules. Compositions and microarrays according to the invention are useful in any type of analytical or preparative procedure relating to biomolecules. They are particularly useful, e.g.

Abstract: This invention provides a simple and convenient, single stage, single vessel cell extraction and assay method which is suitable for the extraction and measurement of a range of different types of analyte which occur as cellular components. The invention also provides kits of reagents suitable for performing cellular extraction and measurement as a single stage, single vessel process.

Abstract: A method for assay of an analyte by use of a material labeled with a chemiluminescent substance, which comprises adding a quencher and/or decreasing the specific activity of a chemiluminescent substance labeled probe, thereby decreasing the quantity of chemiluminescence.

Abstract: A method is disclosed for determining whether a compound binds to a lipoprotein such as LDL or VLDL in a manner which will lower plasma cholesterol. The method provided includes assessing the ability of the compound to form a complex with the lipoprotein, and then determining whether the newly formed complex causes a change in the structure of apoB-100 that results in increased binding affinity to an LDL receptor.

Abstract: Analytical reagents and mass spectrometry-based methods using these reagents for the rapid, and quantitative analysis of proteins or protein function in mixtures of proteins. The methods employ affinity labeled protein reactive reagents having three portions: an affinity label (A) covalently linked to a protein reactive group (PRG) through a linker group (L). The linker may be differentially isotopically labeled, e.g., by substitution of one or more atoms in the linker with a stable isotope thereof. These reagents allow for the selective isolation of peptide fragments or the products of reaction with a given protein (e.g., products of enzymatic reaction) from complex mixtures. The isolated peptide fragments or reaction products are characteristic of the presence of a protein or the presence of a protein function in those mixtures. Isolated peptides or reaction products are characterized by mass spectrometric (MS) techniques.

Abstract: Reagents and the use of the reagents in a microparticle light scattering agglutination assay are disclosed. The reagents comprise a mixture of particles having relatively stronger light scattering properties and particles having relatively weak light scattering properties with respect to one another. The particles having strong light scattering properties carry a binding partner of high reactivity with the analyte. The particles having weak light scattering properties carry a binding partner of low reactivity with the analyte.

Abstract: A wafer-scale module includes a plurality of stacked wafers, each having a thin semiconductor layer disposed on a surface of the wafer, a plurality of wafer-scale integrated (WSI) circuits formed on the semiconductor layer and a plurality of nodes formed on the semiconductor layer. Each node provides an optoelectronic interface to an axial optical waveguide for high-speed optical interconnectivity between the WSI circuits and other integrated wafer circuit devices of the stack. A top plate is included and is disposed on the plurality of stacked wafer devices. A base plate, included for purposes of thermal dissipation, is disposed opposite the top plate such that the plurality of stacked wafers are sandwiched between the top plate and the base plate and all are assembled.