Abstract: A method and apparatus for the manipulation of colloidal particulates and biomolecules at the interface between an insulating electrode such as silicon oxide and an electrolyte solution. Light-controlled electrokinetic assembly of particles near surfaces relies on the combination of three functional elements: the AC electric field-induced assembly of planar aggregates; the patterning of the electrolyte/silicon oxide/silicon interface to exert spatial control over the assembly process; and the real-time control of the assembly process via external illumination. The present invention provides a set of fundamental operations enabling interactive control over the creation and placement of planar arrays of several types of particles and biomolecules and the manipulation of array shape and size. The present invention enables sample preparation and handling for diagnostic assays and biochemical analysis in an array format, and the functional integration of these operations.

Abstract: In an automated analyzer containing a spectrophotometer for determining color changes in a urine sample the urine is admixed with a basic indicator effecting the first color change and an acidic indicator effecting a second color change, a surfactant and water. The spectrophotometer determines and prints whether a first or second color change has occurred.

Abstract: Colored indicator for measuring the distribution of hydrocarbon families contained in a mixture, a procedure for obtaining it and its uses. In the colored indicator, the colorants that are able to be eluted with the family of aromatic hydrocarbons are free of organic compounds having an affinity with oxygenated compounds containing at least 6 carbon atoms.

Abstract: A method for the quality control of nucleated red blood cells on a hematology analyzer using a mixture of human and animal blood, particularly chicken blood and fixed human blood with nucleated red blood cells. The control material illustrated good stability over a fifty day period when stored at 4 degrees Celsius. The cell morphology showed good cell shape and the equipment had a stable nucleated red blood cell number and nucleated red blood cell per 100 white blood cells number. The method is used for quality control as for calibration for nucleated red blood cell counting or staging, on a hematology analyzer.

Abstract: A method is disclosed for diagnosing early stage of a disease in which an intact protein found in urine is an indicator of the disease. The method includes assaying urine sample to detect the presence of modified protein using either immunological or non-immunological technique. Methods for preventing and treating the disease are also disclosed.

Abstract: The invention relates to a method for rapid measurement of acidity in juice. A sample vial is quantitatively filled with juice and transferred to a mixing vessel. A drop of pH indicator solution is added to the mixing vessel. While swirling to mix, a calibrated dropper is used to add a known concentration of titrant. The titrant is added and the number of drops that are required to cause a color change is noted. The number of drops of titrant used is multiplied by a predetermined conversion factor to generate a percent acidity value appropriate for the sample type. Different concentrations of titrant or different volumes of sample, with different conversion factors, are used, depending on the level of acidity expected in the sample. The method is rapid, with accuracy and precision comparable to traditional burette titrations.

Abstract: Self-contained systems test for the presence of occult blood in a specimen. In one embodiment, the system has a test matrix comprising a testing portion spaced apart from a medium entrance portion, wherein the testing portion has a specimen placement area on a first side and a result area on an opposing second side. The system also has a container holding a developing medium, wherein the container is adapted to release the developing solution onto the solution entrance portion. A housing holds the test matrix and the container. The housing has a specimen opening at the specimen placement area and preferably is adapted to enable the result area to be observed. The developing medium preferably is a free standing liquid within the container. The developing medium is released from the container upon compression or breaking of the container.

Abstract: A novel reagent system for use with automated and semi-automated hematology analyzers including an essentially isotonic blood diluting reagent, a blood cell lysing and hemoglobin conversion reagent, and a second lysing reagent for differentiating white blood cells into classes by size and functional characteristics. The diluent reagent enhances properties for counting and sizing blood specimens, while stabilizing cellular volume and cellular integrity for many hours. The blood cell lysing reagent removes red blood cells and enables subsequent enumeration of white blood cells and simultaneous determination of hemoglobin without use of the toxic cyanide anion. The third lysing reagent and a companion quenching differentiates blood cells into classes by size and functional characteristics, based on d.c. impedance volume, conductivity/opacity and light scatter measurements. The companion quenching reagent adjusts pH and conductivity of the final measurement solution to match the analyzer system requirements.

Abstract: The invention relates to an assay for testing oxidative stress of a subject by measurement of oxidants in biological fluids such as urine, plasma, bioreactor medium and respiratory aspirants. There is provided a method of determining oxidative stress in a mammalian subject. The method comprises: obtaining a sample of a biological fluid from the subject; mixing the biological fluid with a ferrous reaction reagent; incubating the biological fluid and the reaction reagent; and detecting a colored reaction product.

Abstract: In a process for the quantitative optical analysis of fluorescently labelled biological cells 5, a cell layer on a transparent support at the bottom 2 of a reaction vessel 1 is in contact with a solution 3 containing the fluorescent dye 4. The sensitivity of analytical detection can be considerably improved if to the fluorescent dye 4 already present in addition a masking dye 9, which absorbs the excitation light 6 for the fluorescent dye 4 and/or its emission light 7, is added to the solution 3 and/or if a separating layer 10 permeable to the solution and absorbing and/or reflecting the excitation light 6 or the emission light 7 is applied to the cell layer at the bottom 2. The separating layer 10 must be composed such that it has a high power of reflection for the luminescent light 11.

Abstract: A composition of matter suitable for use in a reversible thermometer is disclosed which comprises a thermally responsive material capable of being supercooled at least for several minutes, and subject to a change in state from a solid to a liquid substantially at a predetermined temperature; means for visually observing the change in state; and a matrix forming material comprising an amorphous organic compound, the matrix forming material being insoluble in the thermally responsive material; whereby the thermally responsive material is dispersed within the matrix forcing material, the composition of matter being reversibly responsive to changes in temperature, and remaining in the liquid state for a time sufficient to permit a user of the composition to observe the change in state. The preferred matrix forming material is polyisobutylene, and the preferred thermally responsive material is a solid solution of ortho-chloronitrobenzene and ortho-bromonitrobenzene.

Abstract: A method, system and kit for detecting the presence of an analyte includes placing a solution containing the analyte in a microcapillary tube and placing the microcapillary tube in contact with a layer of sorbent material so that the solution is withdrawn from the microcapillary tube by capillary action. The sorbent material and solvent for the solution are selected so that the solvent is absorbed into the sorbent material and the analyte is adsorbed by the sorbent material and concentrated at the spot where the microcapillary tube contacts the sorbent material. A detector reagent is applied to the sorbent material to indicate the presence of the analyte.

Abstract: A test strip for simultaneously measuring a plurality of analytes in blood or other fluids comprising a plurality of reagent pads containing reagents specific to particular analytes located on a support. Each reagent pad is covered and in close contact with a sample distributing layer and an optional blood filtering layer. Color produced by analytes in the sample is viewed through apertures in the support. The colors of the pads are read simultaneously with an instrument such as a reflectance meter containing individual LED's as light sources for each reagent pad. The intensity of the color of the individual pad can be used to detect semi-quantitative or quantitative concentration of analytes in a sample on site, allowing for quick communication of results to a remote site by electronic means.

Abstract: The invention relates to multicomponent test systems which indicate the concentration of one or more analytes in a liquid sample, as well as the effect of action on the sample which results in an increase or decrease of the concentration of the analyte under consideration. Simulating increase or decrease permits the user to determine if corrective action is necessary, and what that corrective action might be. Both dry chemistry and wet chemistry systems are described.

Abstract: A chemical indicator of an aurin moiety in a substrate to detect the presence of an oxidizing agent.

Abstract: A fluorescence-based method for highly sensitive and selective detection of molecules of basic gases, such as dimethyl methylphosphonate (DMMP), Sarin, Soman and other chemical warfare agents, is proposed. The method employs the effect of strong fluorescence change in a solvatochromic dye isolated in a matrix of the hydrogen bond acidic polymer. In one preferred embodiment the dye and polymer matrix are chosen such that the hydrogen-bond interaction between them results in depression of the fluorescence yield of the sensitive material prior its interaction with the molecules of basic gases. The interaction between the molecule of basic gases and the acidic polymer matrix breaks the hydrogen bond of the dye with the polymer matrix “releasing” the dye and returning it back into the state with a low solute-solvent interaction. That results in strong enhancement of the dye florescence quantum yield and shift of the dye fluorescent spectrum in the direction of shorter wavelengths.

Abstract: A composition is disclosed for application to a plant that comprises an exogenous chemical (for example, a postemergent herbicide), an aqueous diluent, and a first excipient substance that is amphiphilic. The weight/weight ratio of the first excipient substance to the exogenous chemical is between about 1:3 and about 1:100. The aqueous composition forms anisotropic aggregates on a wax layer, and the presence of the anisotropic aggregates can be detected by a test described herein. Compositions of the present invention, when applied to plants, provide enhanced biological activity per unit amount of exogenous chemical, as compared to otherwise similar compositions containing surfactants that do not form anisotropic aggregates. Without being bound by theory, it is presently believed that this enhanced biological activity results from the formation or enlargement of hydrophilic channels through the epicuticular wax of the plant.

Abstract: A method and apparatus for urine self testing wherein the apparatus is placed directly into the toilet after urination which avoids the direct placement and retention of an apparatus in the stream of urine as is common with urine testing devices. The apparatus detects the presence of certain chemicals in dilute urine such as the presence of human chorionic gonadotropin (hCG) in the urine of a pregnant woman. An opening in the apparatus is fitted with a fluid absorption device which acts to concentrate the diluted urine on an indicator strip which contains antibodies, enzymes and antibody blockers which will provide a reactive change, usually of color, when subjected to a predetermined chemical such as hCG. The apparatus functions in dilute urine when placed in a toilet after urination and is largely constructed of biodegradable materials so that it can be flushed into the sewage system or a septic tank.

Abstract: A kit for labeling cells to determine their viability which includes a first dye for labeling non-viable cells and a second dye for labeling all cells, including non-viable cells in which the dyes are selected to have concentrations suitable for determining the viability of cells in cell suspensions having different cell viability.

Abstract: A test glass slide for an automated biological reaction apparatus is disclosed. The test slide monitors to operational temperature of the apparatus for maintenance/quality control purposes by means of at least two temperature-sensitive indicators, which change visual states once a predetermined temperature threshold is reached. The thresholds correspond generally to the specified temperature range for the protocol performed by the apparatus.

Abstract: The present invention relates to new color compositions which are especially suitable to be used in oxygen indicators. The compositions comprise iron(II), an agent containing pyrogallol entities and an organic acid.

Abstract: A test kit for determining the “volatile ammonia content” of biological samples comprising any wet or dry compost, manure, plasma or soil sample. The kit includes a transparent container for holding the sample, and a reactant chemistry gel system, located within the container in the space not occupied by the sample. The reactant mass includes an acidic pH reactant material, and a color change indicator material, responsive to pH changes in the reactant material. Ammonia vapors diffuse into the reactant material, reacting chemically with the acidic pH reactant material so as to produce a color change. The nature of the color change is an indication of the quantity of NH3 in the test-jar atmosphere, which in combination with the known pH of the sample, indicates the total ammonium in the biological sample.

Abstract: Homogeneous fluorescence polarization (anisotropy) assays for detecting and quantifying metal ions in solution, based the metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule, or the binding of a metal ion to a fluorescent labeled macromolecule. The metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule (metallo-macromolecule) effects a measurable change in anisotropy as will the binding of metal ions to a fluorescent labeled macromolecule. Binding of the fluorescent ligand to the unlabeled macromolecule is metal dependent with the change in anisotropy being proportional to the concentration of bound metal ions. No binding of the fluorescent ligand to the macromolecule occurs in the absence of metal ions. Conversely, if the fluorescent label is first conjugated to a metallo-macromolecule and the metallo-macromolecule is subsequently stripped of its metal ion, it may then be used to transduce the binding of metal ions.

Abstract: Test devices and methods are provided for detection of feline lower urinary tract disease. The test devices comprise a matrix impregnated with a color indicator and a stabilizer wherein the indicator remains stable when exposed to ambient conditions and wherein a positive color response remains stable for a sufficient time for the color response to be observed. The test devices may be provided for use in combination with conventional cat box filler.

Abstract: A visual indicating paste composition for detecting of aqueous solutions in hydrocarbons by changes in color. The paste is utilized by placing on a probe and inserting the probe in a storage device for fuel. Said paste comprising: a) a liquid carrier selected from high molecular weight polyols; b) a caustic powder selected from alkaline earth oxides; c) a gelling agent; d) a surfactant consisting of ethoxylated nonylphenol with 9 moles of ethylene oxide; e) a filler material. f) a water scavenger consisting of aluminum isopropoxide; g) an indicator dye; and h) a neutral dye; wherein the paste of the present invention will change color upon contact with an aqueous solution in the pH range of about between 7 and 11.

Abstract: The subject invention relates to processes of measuring molecular mass by mass spectrometry, in particular to methods of precise calibration of mass spectrometers, and to kits and systems for use in calibrating mass spectrometers.

Abstract: A method for determining copper (I) concentrations in water or seawater samples. In the method a probe is dipped into the sample for a time sufficient to produce a color change, removed and compared to a color standard to determine the concentration. The probe includes a substrate and an impregnate, bathocuproine, which complexes to copper (I) to produce a colored complex that is not toxic or less toxic to marine organisms than copper (I). The substrate is an ionomeric polymer having hydrophobic chains with hydrophilic cation exchange cites. In a preferred embodiment the substrate is a sulfonated perfluoropolymer.

Abstract: A dye compound having the formula I: wherein, n is 0, 1, 2, or 3; R1 is H, alkyl, or an alkoxy group; R2 is CH2(CH2)mOH, wherein m is 0, 1, 2, or 3; X is O, S, or C(CH3)2; R is CH3, CH(CH3)2, CH2CH2OH, alkyl, alkylsulfonate, or hydroxyalkyl and B− is a counteranion. Red- and blue-excitable dyes based on the above chemical structure are described, and reagents containing them are described for use in staining nucleic acid, more particularly for staining reticulocytes. Also described are methods for detecting reticulocytes using such compositions.

Abstract: The present invention provides an ozone processing monitor and a method of using the same in ozone processing to determine whether sufficient ozone treatment has occurred on a production part needing ozone treatment. The ozone processing monitor of the present invention comprises an ozone sensitive material which is capable of thinning, bleaching, forming an oxide layer or undergoing any other physical or chemical change upon exposure to ozone, wherein said physical or chemical change produces a visible color change of said ozone sensitive material which can be monitored during or following ozone processing. The color change of the ozone sensitive material can be compared to standards to determine if too little, too much or appropriate ozone treatment has occurred.

Abstract: The invention relates to indicator molecules for detecting the presence or concentration of an analyte in a medium, such as a liquid, and to methods for achieving such detection. More particularly, the invention relates to copolymer macromolecules containing relatively hydrophobic indicator component monomers, and hydrophilic monomers, such that the macromolecule is capable of use in an aqueous environment.

Abstract: A composition capable of showing a color change sufficient for indicating the presence and/or concentration of a protein in a protein-containing liquid sample by contacting with the sample, comprising: indium or an indium compound, and a dye or pigment capable of forming a complex with indium.

Abstract: A method and apparatus are provided for quantifying molybdate corrosion inhibitor concentrations in lithium halide brines of absorption refrigeration systems. This permits monitoring and control of the inhibitor level. A reagent is chosen for reacting with the molybdate in the brine to provide a readily identifiable characteristic color, the intensity of which is a function and measure of the molybdate concentration. The reagent is an acidified reducing agent which reacts to provide a significant characteristic color capable of optical detection without interference. In a lithium bromide brine, the molybdate concentration is conveniently identified by reaction with stannous chloride SnCl in hydrochloric acid Hcl (). The resulting color corresponds to a wavelength of about 550-560 nm (pink), and the intensity is a function of molybdate concentration. Portable measuring equipment, such as a hand held spectrophotometer, or colorimeter, provide a convenient means for making on-site measurements.

Abstract: The present invention generally relates to analytical elements and methods for the selective determination of magnesium. In particular, the present invention is further directed to carboxy-quinolizine suitable for use as magnesium indicators, and more particularly, to 4-oxo-4H-quinolizine-3-carboxylic acid derivatives for use as novel fluorescent magnesium indicators.

Abstract: The present invention relates to a method for determining the concentration of oxygen-centered free radicals in a sample. The method uses a chromogen chosen from the following group: with R1, R2, R3, and R4 being —CH2CH3, —CH3, —H, or —X, with X being a halogen. The method includes combining a working reagent having a selected chromogen and a buffer with a sample containing free radicals. Quantitative determination of the concentration of the free radicals in the sample is then determined, based on the chromogenic reaction which takes place.

Abstract: The invention provides a method for producing a micro-carrier, which includes patterning pluralities of bar code on a mask; exposing the bar code to a substrate coated with photoresist; etching and removing residual photoresist and electroforming to a nickel plate; placing a bead coated with biotin or poly-L-lysine between two-nickel plates, and compressing the bar code on the surface of the bead to form a microcake-like particle with bar code; and combining the particle with the corresponding bio-molecule thereof to produce a micro-carrier with a label. The invention also provides a test method for identifying a bio-molecule, which includes mixing several micro-carriers with the labeled unknown bio-molecules; and identifying the bar code on the micro-carrier via image recognition system, wherein the numbers and types of the known micro-carrier can be flexibly adjusted.

Abstract: A device for assay of a liquid sample. The device comprises: a support composed of an organic macromolecule, said support having a surface divided into two areas located adjacent to each other; a divider in the surface, defining the border of both areas to separate a first area from a second area; a detection layer affixed to the first area and containing a reagent; and a water-swelling layer affixed to the second area, said water-swelling layer expanding by absorbing water.

Abstract: A rapid colorimetric assay is provided for determining the concentration of vanadyl and vanadate ion species, and total vanadium concentration, in a sample. A sample suspected of containing vanadium in one or more of these oxidation states is combined with a colorimetric substrate that will provide for different absorption spectra with vanadyl and vanadate complexes. Suitable colorimetric substrates include halogenated hydroxyquinolines, e.g. broxyquinoline (DBHQ). The solvent and assay conditions are chosen to minimize oxidation of the vanadium. The absorbance of the sample is then read at two wavelengths, one that indicates the presence of both vanadyl and vanadate, and one that indicates the presence only of one species, generally vanadate. By comparison to a standard curve, the total concentration and the species concentration of vanadium in the sample is determined.

Abstract: Compositions and methods for determining the presence or concentration of an analyte in a sample by exposing the sample to an indicator molecule comprising a fluorescent lanthanide metal chelate complex. The presence or concentration of the analyte in the sample is determined by observing and/or measuring the change in intensity of fluorescence emitted by the lanthanide metal chelate complex upon binding of the analyte to one or more recognition elements in the complex. The fluorescent indicator molecules can be used in various types of fluorescent sensing devices and are useful in various fields, including energy, medicine and agriculture.

Abstract: The present invention provides an object, which, in its outer surface contains a color-forming composition which comprises a solvent-absorbing material that is generally a polymer; a color-former compounded with the solvent-absorbing material, where the color-former functions as a metal chelating agent; and metal ions capable of forming a chelate complex with the color-former as the solvent-absorbing material absorbs a solvent, resulting in a detectable color change of the composition. The present invention also provides a method for indicating exposure of the color-forming composition to a solvent, wherein the color-forming composition is to be used on the outside surface of objects.

Abstract: Composition containing two components, which together show an elevated freezing point and bring about a color change at selected temperatures and method of making the same. Use of the composition to prepare a temperature indicating device by filling the same in a suitable transparent container and with a background in the form of a color, a number or a letter, which facilitates to visually observe the difference in color change.

Abstract: The invention provides monoclonal antibodies and other binding agents to human cytochrome P450 1A2 having advantageous properties, including capacity substantially to inhibit enzyme activity of human cytochrome P450 1A2 and lack of specific binding to other human cytochromes P450. The binding agents of the invention are useful inter alia in methods for screening drugs for metabolism by cytochrome P450 1A2, and in methods of measuring p450 1A2 levels in individuals relative to p450 1A2 levels in a control population.

Abstract: Methods for assay of both total bilirubin and direct bilirubin in a sample. The inventive methods enable the amounts of total and direct (conjugated) bilirubin to be colorimetrically measured in about 5 minutes, and do not require the precipitation and removal of potentially interfering substances such as proteins prior to analysis. Novel stable reagents that solubilize the bilirubin and interfering substances are also provided. A novel total bilirubin reagent causes the oxidation of the total bilirubin in the sample, and the formation of a light-absorbing bilirubin chromophore detectable in the near-infrared region of the spectrum. A novel direct bilirubin reagent causes the oxidation of the direct bilirubin in the sample, and the formation of a light-absorbing bilirubin chromophore detectable in the near-infrared region of the spectrum, whereas the chromophore formed by the unconjugated bilirubin is substantially colorless.

Abstract: In view of the situation of the prior art, the present invention specifies the structure of a late-stage product of Mailard reaction in vivo having a close relation with various tissue disorders, and provides a diagnostic reagent for complications associated with diabetes or renal failure, containing the above compound as a main component.

Abstract: The present invention provides a reagent for extracting lead ions from a variety of biological matrices such as human whole blood that has been anticoagulated with either heparin or EDTA, and lyophilized human blood and bovine EDTA whole blood. The released lead is measured in situ with a calorimetric porphyrin reagent without further manipulation of the supernatant. The lead ion releasing reagent can be used in conjunction with a variety of assay formats for the determination of lead in various biological fluids.

Abstract: The invention provides monoclonal antibodies and other binding agents to human cytochrome P450 2A6 having advantageous properties, including capacity substantially to inhibit enzyme activity of human cytochrome P450 2A6 and lack of specific binding to other human cytochromes P450. The binding agents of the invention are useful inter alia in methods for screening drugs for metabolism by cytochrome P450 2A6, and in methods of measuring p450 2A6 levels in an individual relative to p450 2A6 levels in a control population.

Abstract: The method measures hydrogen sulfide concentrations in hydride gases in a sealed vessel. The sealed vessel has a gas inlet to receive a stream of hydride gas, a gas outlet to remove the stream of hydride gas and a metal acetate substrate. The stream of hydride gas contains a concentration of hydrogen sulfide gas. Introducing the stream of hydride gas through the gas inlet contacts the acetate substrate with the stream of hydride gas. Reacting the hydrogen sulfide gas contained in the stream of hydride gas with the acetate substrate modifies optical properties of the acetate substrate. Then measuring the optical properties of the acetate substrate determines the concentration of the hydrogen sulfide gas contained in the stream of hydride gas.

Abstract: The present invention provides screening methods for identifying compounds which induce tardive dyskinesia (TD) when administered to an animal. In particular, the methods involve assaying for intermediates and end products of reactions associated with candidate compound mediated reduction of reducible substrates. Also provided are high-throughput screening methods for determining whether compounds induce TD when administered to an animal. Further, provided are methods for treating psychoses comprising testing antipsychotic drugs to identify those which will not induce TD when administered to an animal and administering one or more such drugs to a patient in need thereof.

Abstract: A method of protein precipitation, concentration and removal of non-protein agents from the protein solution wherein the protein solution is treated with a protein-precipitation agent containing an acidic agent, a salt and a precipitate forming agent. After precipitation, the protein precipitate is washed with a water miscible organic solvent agent to remove non-protein agents present in the protein precipitate.

Abstract: In accordance with the present invention, there are provided articles for use in non-invasive measurements of nitric oxide levels in a variety of fluid media, e.g., in mammalian body fluids. Articles according to the present invention comprise a nitric oxide trapping agent contained within a vessel, wherein the vessel comprises a semi-permeable membrane. Nitric oxide diffuses through the semi-permeable membrane and is trapped therein for subsequent quantitative analysis. Articles of the present invention are particularly useful in selectively detecting nitric oxide in the presence of other NOx species.

Abstract: Microporous solid phase materials that are suitable for lateral flow and other assays for detecting the presence of analytes in test samples, that are stable under variations in humidity and, even after storage for extended periods of time, can form stable covalent bonds with molecules containing a free primary or secondary amine group or sulfhydryl group are described. The invention further concerns chemically derivatized solid phase materials, and conjugates comprising such materials. Examples of lateral flow devices for the quantitative or semi-quantitative determination of an analyte in a biological sample are described.