Abstract: Reference controls comprised of aldehyde-fixed white blood cells stabilized red blood cells and simulated blood platelets exhibiting a white blood cell histogram profile that is substantially that of whole blood are obtained by the addition of a lipoprotein to the control and an antioxidant to inhibit lysis of stabilized red blood cells by said lipoprotein.

Abstract: A hematological specimen for classifying and counting leukocytes with a flow cytometer is prepared. A sample to be assayed is prepared by eliminating influences of erythrocytes from a hematological sample without changing leukocytes morphologically by adding a first aqueous solution of a low osmotic pressure including a buffer for adjusting the pH value within an acidic region and a second aqueous solution including an osmolarity compensating agent and a buffer for giving pH value suitable for staining, optionally further adding a salt, which dissociates into ions in aqueous solutions so as to control the electrical conductivity of the aqueous solution at a preferable level, while damaging the cell membranes of erythroblasts contained in said sample; and staining the leukocytes with at least four dyes including Astrazon Yellow 3G and Neutral Red.

Abstract: A non-toxic composition, and method, for the clarification of raw sugar-containing juices, especially sugar cane juice, and related products, for analysis. A composition constituted of A) aluminum chloride hydroxide, B) lime and C) activated bentonite, bentonite containing calcium aluminum silicate, and preferably also a polymeric flocculating agent, has been found highly effective as a reagent for the clarification of sugar-containing juices, notably sugar cane juice, and related products.

Abstract: A lytic reagent composition highly selective in its interactions with the cell membranes of blood cells and also provides a method of using the reagent composition in a semi-automated or an automated system to effect a significantly improved white blood cell differential determination. The lytic reagent composition is characterized by an ability to selectively shrink the white blood cells into the increasing size order of lymphocytes, a midregion consisting mainly of monocytes, other mononuclear cells, some basophils and eosinophils, and neutrophils and can readily be optimized to effect a significantly improved three component separation on the histogram of commercially available semi-automated and automated blood analyzers when compared to the reagents conventionally employed on such instruments.

Abstract: A process and a composition for the removal of turbidity from biological fluids by the addition of surface-active agents, which is characterized in that the surface-active agents used area. an alkyldimethylbenzylammonium compound,b. a polyethoxylated triester of sorbitan or sorbiol with long-chain fatty acids,c. optionally, an amphoteric surfactant,d. optionally, a buffer, ande. optionally, a saltin aqueous solution.

Abstract: Use of a lithium salt, particularly lithium thiocyanate, as an agent for lysing red blood cells and denaturing hemoglobin in the performance of an immunoassay to detect the relative amount of a hemoglobin derivative in a blood sample. The method is particularly useful in the determination of hemoglobin Alc. The method provides a rapid means for releasing hemoglobin from red blood cells by lysis and for exposing the epitope that is characteristic of the Alc form. Low concentrations of the lithium salt provide rapid release and denaturation of hemoglobin without the need for dilution prior to the performance of the immunoassay.

Abstract: An aqueous alcohol buffer solution for substantially ambient, in vitro preservation of mammalian cells for a selected duration. The solution generally contains a water-miscible alcohol in an amount sufficient to fix the sample cells without coagulation, an anti-clumping agent, and a buffer agent to maintain the solution at a pH within a range of four to seven.

Abstract: A new method for separation of white cells in differential hematology instruments is described. In the method described, white cell shrinkage is controlled by the use of diazolidinyl urea and accelerated with alcohol thereby providing a reproducible method for easy manipulation of the white cells. In addition, it was found that adsorption of blood platelets and red blood cells in the instruments can be prevented by use of a surfactant such as the polyols.

Abstract: A reagent for measuring the hemoglobin concentration and counting the number of leukocytes in a blood sample, which contains at least one of a quaternary ammonium salt or a pyridinium salt, having a concentration capable of hemolyzing erythrocytes in the blood and denaturing hemoglobin and at least one of cationic, nonionic or amphoteric surfactants or an oxidant capable of oxidizing heme in hemoglobin, the reagent being capable of dividing leukocytes into two or three fractions, for example, a fraction of lymphocytes, a fraction of monocytes, eosinophils and basophils, and a fraction of neutrophils.

Abstract: A reagent, satisfying the undermentioned conditions, is useful for counting the number of leukocytes and measuring the hemoglobin concentration in blood samples. The reagent is free of cyanides and it is able to maintain hemoglobin in a stable state for a prolonged time. The reagent contains at least one cationic surfactant selected from the group consisting of a quaternary ammonium salt of a concentration capable of hemolyzing erythrocytes in the blood and oxidizing hemoglobin and a composition of pyridinium salts; at least one cationic, nonionic or amphoteric surfactant; and at least one hemoglobin stabilizer.

Abstract: The present invention relates to a reagent and to a method of using the same for automatically determining at least one leukocyte sub-population from a total blood sample. Using this reagent, it is possible, in a single step, to lyse the erythrocytes through the action of saponin and SDS, as well as to ensure the differential staining of the leukocyte sub-populations, at the same time preserving the integrity and morphology of the cells, through the combined action of various components including chlorazol black, an alcohol, a surfactant and preserving agents. The reagent according to the invention can be applied to different types of automatic flow cytometry analyzers.

Abstract: A multi-phase control and/or calibration system consists of a liquid phase containing an amount of dissolved oxygen (O.sub.2) in which the O.sub.2 partial pressure is made relatively temperature insensitive over an ambient temperature range of interest, and an amount of dissolved carbon dioxide (CO.sub.2) and one or more solute species that provide temperature stability with respect to the partial pressure of CO.sub.2 over the ambient temperature range of interest. The liquid phase is in equilibrium with a vapor phase and the system sealed with a storage atmosphere.

Abstract: An improved multi-purpose blood diluent for use with a gentle lysing agent and improved detergent reagent system are disclosed which are especially suitable for use in routine electronic enumeration and volumetric differentation of blood cells. The preferred imidazole stabilizer used in the diluent reagent is found to be an excellent cell stabilizing agent and buffer for maintaining cell morphology during operation. A synergistic combination of a superior antimicrobial agent, the preferred Triadine-10, used in the diluent and the detergent reagents, not only prevents bacterial or fungal growth, but also helps to stabilize cells and to obtain distinct volumetric differentiation of certain leukocyte subpopulations. The preferred Brij 35 in a balanced salt solution has proved to be an efficient and cost effective detergent to ensure accurate results and trouble-free operation of the analyzers.

Abstract: A formulation of combined-composition electrolyte and pH buffers for use as standardization solutions in analyzers for clinical chemistry which simultaneously use more than one ion-selective electrode plus more than one standard solution. Each ion is present in the standard solution in stoichiometric quantity such as to compensate the effect due to the incomplete dissociation of the salt used, and to obtain an activity coefficient and liquid junction potential such as to reduce the error generated by the use of standardization solutions which do not take account of these quantities. Buffer solutions are described having a pH within the range of 6-8 and an electrolyte compositions (Na.sup.+, K.sup.+, Ca.sup.+ and Cl.sup.-) which reflect the composition of the biological liquid to be analyzed, namely whole blood, plasma or serum, in equilibrium with different partial pressures of oxygen and CO.sub.2.

Abstract: A colorimetric, particularly spectrophotometric, method and compositions for determining calcium levels in blood serum in the presence of magnesium and other serum ions is described. The method uses an aqueous composition with a pH between about 7.5 and 10 with arsenazo III to complex calcium and a hydroxyquinoline selected from the group consisting of 8-hydroxyquinoline and 8-hydroxyquinoline-5-sulfonate to complex magnesium. Lipase and a cyclodextrin can be used as reagents to clear triglycerides in the serum which can provide turbidity and false results in some instances. The method is particularly useful for human serum.

Abstract: An aqueous wash solution is useful for the detection of herpes simplex virus in a biological specimen. This solution has a pH of from about 9 to about 11.5, and consists essentially of an alcoholamine or a salt thereof and a nonionic surfactant. The solution is used to was uncomplexed materials from a complex of herpes simplex antigen and antibodies thereto. The wash solution can be supplied as part of a diagnostic test kit.

Abstract: A method for preparing a fecal sample for immunoassay testing comprising the steps of dispersing a sample of from 1 to less than 10 wt. % of a stool sample in an aqueous fecal test solution formulated with one or more preservatives, analyte stabilizing agents and endogenous interference reducing agents. The fecal solids are then permitted to settle to form a liquid phase substantially free from fecal solids, and the clarified liquid phase is removed to provide a test sample free from fecal solids. The fecal test solutions contain suitable stool stabilizers such as buffers and antimicrobial agents, analyte protecting agents such as proteolytic, reductive or oxidative enzyme inhibitors, endogenous assay interfering enzyme inhibitors such as a reducing agent, and non-specific binding inhibitors such as animal proteins. The stool sample should be fresh or be fresh frozen and thawed immediately before dispersion in the buffer solution.

Abstract: Specified classes and subclasses of leukocyte blood cells are identified by immunohematology procedures, based on utilization of antigenic determinants on the cell surface, their reactivity with antibodies which fluoresce under known circumstances, and identified by utilization of principles of flow cytometry or morphology.This invention particularly concerns improvements in the lysing and fixing method used prior to detection and identifying of the cells. In this method, a whole blood sample first is incubated with a reagent including antibodies to the cell subclass to be identified, the antibodies having directly or indirectly made fluorescently responsive to a particular light (e.g. argon ion laser). The red blood cells then are lysed with a reagent containing saponin. Next follows a leukocyte fixing treatment, preferably using a cross-linking dialdehyde composition, such as glyoxal or glutaraldehyde.

Abstract: In order to calibrate a measurement apparatus used for determining at least the pH and pCO.sub.2 values in aqueous media, two aqueous base solutions A and B with good storage stability are mixed at a defined ratio immediately prior to calibration, the desired pH and pCO.sub.2 values being provided for calibration of the measuring electrodes of the measurement apparatus only after chemical reaction of the base solutions A and B has taken place.

Abstract: A lysing reagent is employed for stromatolysing the red cells in a blood sample and differentiating the leukocytes into subpopulations. The lysing reagent contains a dodecyltrimethylammonium halide and an aromatic second cationic agent which is either a benzyltrialkylammonium halide or an alkylpyridinium halide. In some methods, the lysing reagent is mixed in the reaction chamber with a major proportion of the diluent, and the blood sample with a minor proportion of the diluent is added to the reaction chamber.

Abstract: Three methods for classifying leukocytes with a flow cytometer by optical measurements on fluorochrome-stained blood cells or those which have been so treated as to provide varying intensity in forward scattered light are useful in the practice of clinical testing. Also included are reagents employed in the practice of such methods.

Abstract: A reagent for classifying leukocytes with a flow cytometer by means of optical measurements on fluorochrome-stained blood cells is included. The reagent is useful in the practice of clinical testing and includes a Neutral Red fluorochrome and either an Astrazon Organe G or an Auramine O fluorochrome to enable differentiation of leukocytes.

Abstract: A process for the removal of non-specific turbidities in the carrying out of determinations according to the immuno-assay principle, wherein an inorganic boron compound is added to the sample solution in combination with a buffer system.

Abstract: A method and reagent system are disclosed for the rapid isolation, identification and/or analysis of leukocytes from a whole blood sample. The method and reagent system of this invention has application to any environment in which the study and/or analysis of the leukocyte fraction of whole blood requires their isolation in their native or near native state. One of the environments in which this invention can be used to advantage is in the performance of white cell differentiation on automated instrumentation designed for that purpose. In one of the preferred embodiments of this invention, the lytic reagent can contain a mixture of both formic and acetic acid, with the formic acid comprising the major component thereof and the acetic acid being present in only minor quantities, (if at all). This reagent system is used to selectively effect stromatolysis of red blood cells and create subtle modifications to the leukocyte population to enable their automated differentiation into five (5) sub-populations.

Abstract: Use of a lithium salt, particularly lithium thiocyanate, as an agent for lysing red blood cells and denaturing hemoglobin in the performance of an immunoassay to detect the relative amount of a hemoglobin derivative in a blood sample. The method is particularly useful in the determination of hemoglobin A1c. The method rapidly releases hemoglobin from red blood cells by lysis and exposes the epitope that is characteristic of the A1c form. Low concentrations of the lithium salt provide rapid release and denaturation of hemoglobin without the need for dilution prior to the performance of the immunoassay.

Abstract: A precipitation reagent for use in analytical systems for the determination of hydrophobic analytes in a biological test sample, particularly analytical systems employing specific binding proteins for such analytes. The precipitation reagent precipitates interfering proteins, hemoglobin, and other interfering substances from a biological test sample while, at the same, maintaining hydrophobic analytes in solution and minimizing the denaturation of specific binding proteins, such as, for example, antibodies, which may be present in an immunoassay system. The precipitation reagent comprises a zinc salt, a glycol, and a straight or branced alcohol from about 1 to 4 carbon atoms, and may optionally contain an acid. A preferred precipitation reagent comprises zinc sulfate, methanol and ethylene glycol, and is particularly useful in a fluorescent polarization immunoassay for the determination of hydrophobic analytes, especially cyclosporine.

Abstract: A device for determining HDL cholesterol by obtaining plasma from whole blood and determining the HDL cholesterol level from the plasma. The device includes an inert substrate support or an active substrate support (e.g. one or the other layers), a physical transport medium, a microporous plasma separation membrane connected to the physical transport medium, at least one plasma collecting test membrane, a filtering membrane, LDL and VLDL reactants to form LDL and VLDL precipitates and an optional carrier precipitation membrane. The plasma collecting test membrane has reactants which will react with HDL cholesterol and indicate the HDL cholesterol level quantitatively. The filtering membrane may be located between the microporous plasma separation membrane and the transport medium or between the microporous plasma membrane and the plasma collecting test membrane and its function is to block the precipitated particles from reaching the test zone.

Abstract: A reagent for the detection and quantitative determination of leukocytes by measuring the myeloperoxidase (MPO) activity of biological samples, which is sensitive for disclosing even only a few leukocytes, without interferences caused by hemoglobin even in the presence of several erythrocytes, and suitable for photometric readings in the visible spectrum region. The reagent comprises a buffer, a chromogen, a surface-active agent, at least an alkali metal halide, a hydroperoxide compound and optionally a reaction promoter.

Abstract: An extraction method for lysing chlamydial, gonococcal or herpes organisms and extracting detectable antigen therefrom involves the use of a protease. In particular, the antigen can be effectively extracted from a biological specimen which contains whole blood or mucous using a protease. The extracted antigen can be effectively detected in an immunoassay involving antibodies directed to the antigen. The protease is novel to the process and is obtained from Bacillus subtilisin.

Abstract: Compounds having detergent properties are disclosed. When a modifying reagent is brought into contact with these compounds, the detergent properties are decreased. These compounds are useful, for example, as solubilizing agents for microbial antigens and/or antibodies and for reversibly wetting hydrophobic surfaces. Accordingly, methods are disclosed for increasing the hydrophilic properties of a material, such as a microbial antigen and/or antibody, the methods generally comprising the steps of contacting the material with the compound having detergent properties and a modifiable group, and modifying the compound with a modifying reagent. Kits are also disclosed for use in accordance with this methodology.

Abstract: A method of reducing the viscosity of a body fluid comprises mixing a body fluid with a cationic quaternary ammonium reagent. The body fluid is a mucopolysaccharide-containing body fluid which will be tested for a metabolite.

Abstract: A material and method are described to reduce the non-specific binding of a labelled material, wherein the labelled material comprises a fluorochrome and a specific binding pair member. The invention is particularlly suited to the lysis of peripheral blood wherein a labelled material is used to identify and detect cell populations within a sample of blood.

Abstract: A method for preparing a fecal sample of immunoassay testing comprising the steps of dispersing a sample of from 1 to less than 10 wt. % of a stool sample in an aqueous fecal test solution formulated with one or more preservatives, analyte stabilizing agents and endogenous interference reducing agents. The fecal solids are then permitted to settle to form a liquid phase substantially free from fecal solids, and the clarified liquid phase is removed to provide a test sample free from fecal solids. The fecal test solutions contain suitable stool stabilizers such as buffers and antimicrobial agents, analyte protecting agents such as proteolytic, reductive or oxidative enzyme inhibitors, endogenous assay interfering enzyme inhibitors such as a reducing agent, and non-specific binding inhibitors such as animal proteins. The stool sample should be fresh or be fresh frozen and thawed immediately before dispersion in the buffer solution.

Abstract: A composition is disclosed of blood serum sample preparation for improved, more accurate and precise, electrooptical method for measuring erythrocyte volumes, individually and as an average.

Abstract: A method for detecting pathogen infection in a host is provided. The method comprises lysing phagocytes from the host to release soluble components of the pathogen which are detected subsequently using a specific binding assay.

Abstract: Three methods for classifying leukocytes with a flow cytometer by optical measurements on fluorochrome-stained blood cells or those which have been so treated as to provide varying intensity in forward scattered light are useful in the practice of clinical testing. Also included are reagents employed in the practice of such methods.

Abstract: A method and a kit for separating double-stranded nucleic acid molecules from a mixture containing both single-stranded and double-stranded nucleic acid molecules. The method is particularly suitable for separating hybridized from unhybridized probe nucleic acid.

Abstract: A method for the extraction of ATP from a microorganism which comprises contacting said microroganism with an ATP releasing agent and thereafter contacting the resultant solution with a neutralizing agent which acts substantially to eliminate the distorting effect of the releasing agent on subsequent ATP assay.

Abstract: A water monitoring system, and more particularly a method and kit for detecting the presence of live undesirable or indicator microorganisms in water after treatment of the water with chlorine or bromine.

Abstract: This invention relates to a method for the rapid determination of a differential white blood cell count in a sample, which method comprises:(a) preparing a reagent solution comprisingformaldehyde or paraformaldehyde;a surfactant;a sugar or sugar alcohol; anda buffer; and(b) rapidly mixing the reagent solution with the sample to be analyzed to form a reaction mixture, wherein both the reagent solution and the sample are initially at room temperature; and(c) rapidly heating the reaction mixture to a temperature of from about 62.degree. C. to about 72.degree. C. in order to lyse the red blood cells in the sample and fix the white blood cells in said sample. The invention also relates to the reagent solution of part (a) of the method.

Abstract: An analytical method for determining the relative amount of a particular hemoglobin derivative, e.g., glycated hemoglobin, in a blood sample wherein the amounts of both total hemoglobin and the hemoglobin derivative are measured and related mathematically, e.g., as a percentage. The blood sample is treated with the combination of a thiocyanate salt and an oxidant to denature the hemoglobin in the sample and to convert hemoglobin to met-hemoglobin. Met-hemoglobin is measured spectrophotometrically to give the amount of total hemoglobin present, and the denatured hemoglobin derivative can be distinguished and measured by immunoassay. The presence of the oxidant in the denaturant solution has been found to increase the rate of enaturation of hemoglobin thereby reducing the overall assay time and improving the reliability of the determination.

Abstract: A universal blood diluent for use in hematology analysis is the subject of this invention. The diluent consists of an aqueous solution of 0.4-1.5% by weight of either Na.sub.2 SO.sub.4 or NaNO.sub.3 or a combination of the two. Also included is 0.1-0.4% by weight of a salt of the formula XH.sub.2 PO.sub.4 where X is either Na or K and 0.1-2.4% by weight of a salt of the formula X.sub.2 HPO where X is Na or K. The phosphate salts may be hydrous or anhydrous. A mixture of Na and K phosphate salts may also been employed. The salts should be present in a ratio of from 1:1 to 1:6 (by weight), XH.sub.2 PO.sub.4 :X.sub.2 HPO.sub.4. 0.1 to 1% by weight of one or both of NaCl and KCl is also included. The Na.sub.2 SO.sub.4 and NaNO.sub.3 should be present in a ratio of at least 1:1 (by weight) relative to the chloride salt. The pH of the diluent should be within the range of 6.0-8.0 and it should have an osmotic strength of 200-400 milliosmoles.

Abstract: An isotonic multipurpose blood diluent, and a method for use of this diluent with a weak lysing reagent system which is especially suitable for routine enumeration of traditional hemogram values, and also the determination of lymphoid-myeloid populations of leukocytes, particularly in automatic particle counting systems.This blood diluent is capable of affording accurate, reproducible test results. It is an osmotically balanced aqueous solution of preselected pH containing Procaine hydrochloride for maintaining erythrocyte morphology during operation, N-(2-acetamido)iminodiacetic acid (ADA) as a blood cell stabilizing agent, and bacteriostatic agents including sodium 1-hydroxypyridine-2-thione, and dimethylolurea which, together with the ADA, allow preferential determination of myeloid-lymphoid leukocytes, and other hematological values.The lysing agent is a mixture of an aqueous solution of at least one quaternary ammonium salt having surface active properties, and an alkali metal cyanide.

Abstract: In order to produce a more well defined interface between adjacent cell layers in a centrifuged sample of anticoagulated whole blood, a material which will bond one group of cells together is added to the blood sample prior to centrifugation. The bonding material must produce a high strength bond between one group of cells, but not effect the other cell types. The material is added prior to centrifugation of the blood sample.

Abstract: The method of this invention is applicable to rapid separation, isolation, and purification of DNA or RNA from biological samples. The DNA/RNA may be in double-stranded or single-stranded form. The method is particularly advantageous for resolving genetic DNA or RNA found in bacteria, virus, and mammalian cells, and for use with samples of human bodily fluids and tissues, including stool, sputum, urine, and blood samples. DNA or RNA can be separated effectively from interfering components, particularly proteins, biological pigments and mucopolysaccharides. The method of the present invention can utilize commercially available strong or weak anion exchanger materials with selected solutions of known ionic strength for adsorption and elution.

Abstract: Nuclear isolation media and procedures are described for dissociating discrete, non-agglomerated cell nuclei from animal tissue without the need to use enzyme treatments, centrifugation or the like in order to achieve the desired separation. The media facilitates separation and maintains the nuclear membrane intact and in its normal physiological environment. When a DNA-fluorochrome stain is included in the medium an essentially one step combination nuclear isolation and DNA staining procedure is used to measure DNA in tissue cells by flow cytometry. Rapid and consistant results are obtained and multiple sampling of the same tissue or comparison between whole tissues and their single cell isolates are also described.

Abstract: A lysing agent and a method for utilizing the lysing agent in the identification and enumeration of cells of a select subclass of leucocytes is provided. The lysing agent includes formaldehyde, an alkali or alkaline earth salt of a weak acid and a polyhydric alcohol.

Abstract: A solvent composition useful for the determination of water by the Karl Fischer method, comprises an ethylene glycol monoalkyl ether and a tetraalkylated ammonium salt.

Abstract: A calibration liquid, especially suitable for ion-selective electrodes, containing albumin. This solution is stable and prevents errors by junction potentials or unknown complexing with calcium.

Abstract: This invention relates to a method for the rapid determination of a differential white blood cell count in a sample, which method comprises:(a) preparing a reagent solution comprising;formaldehyde or paraformaldehyde;a surfactant;a sugar or sugar alcohol; anda buffer; and(b) rapidly mixing the reagent solution with the sample to be analyzed to form a reaction mixture, wherein both the reagent solution and the sample are initially at room temperature; and(c) rapidly heating the reaction mixture to a temperature of from about 62.degree. C. to about 72.degree. C. in order to lyse the red blood cells in the sample and fix the white blood cells in the sample.