Abstract: A releasing reagent for releasing, as ionized calcium, protein-bound calcium in a biological sample for measurement of the ionized calcium, together with any ionized calcium originally present in the sample, using a calcium ion specific electrode, the releasing reagent including monochlorocoacetate salt, formate salt, and formic acid, in concentrations sufficient to render the pH of the sample, when mixed with the reagent, in the range of 4.0 to 5.5. Also disclosed is a method of measuring calcium in a liquid sample using such a releasing reagent.

Abstract: Peritoneal inflammation or infection can be detected in a patient by assaying a peritoneal lavage sample from the patient for lysosomal enzymes. This is done by combining the lavage sample with a leukocyte lysing agent and a chromogenic or fluorogenic enzyme substrate specific for lysosomal enzymes. The lysosomal enzymes can then be measured, and the inflammation of infection detected, by measuring the color or fluorescence developed in the sample by action of the enzymes on the substrate.

Abstract: Control serum containing (1) at least one compound of the formula: ##STR1## in which T is hydrogen or methyl, hydroxymethyl or methoxymethylX is hydrogen hydroxymethyl or methyl when Y is hydroxyl, hydroxymethyl or NR.sub.2 ;Y is hydrogen, hydroxyl, hydroxylmethyl or NR.sub.2 andZ is hydroxyl or an --O--CH.sub.2 --CH.sub.2 OH group when Y is hydrogen or hydroxymethyl, or Z is hydroxymethyl or a carboxyl derivative orT is ethyl or isopropyl,X is hydrogen, or methyl, hydroxymethyl or methoxy,Y is hydroxy, hydroxymethyl or NR.sub.2 andZ is a carboxyl derivative;each R independently is hydrogen or an alkyl group with 1 to 2 carbon atoms optionally containing a hydroxy group and/or (2) at least one compound of the formulaHO(CH.sub.2 --CH.sub.2 --O).sub.n H, (II)in which n is an integer from 2 to 8,in an amount sufficient to reduce turbidities in reconstituted serum after previous lyophilization.

Abstract: The present invention provides an agent for the removal of a turbidity in a biological fluid, wherein it contains(a) a polyethoxylated triglyceride with an HLB value of 4 to 14,(b) a secondary n-alkane sulphonate, as well as optionally(c) a futher non- or anionic tenside, in aqueous, optionally buffered solution.

Abstract: A reduced dinucleotide, preferably nicotinamide adenine dinucleotide (NADH), is stabilized in an aqueous base liquid containing propylene glycol, boric acid and a buffer capable of buffering within a pH range of 8-11. The stabilized liquid contains greater than 50% (v/v) water. The remaining volume contains propylene glycol which has been chemically treated to remove oxidants. This reagent may be used by itself or in conjunction with an assay reagent system for use in the clinical laboratory.

Abstract: A method of lyophilizing reagent-coated latex particles which results in a product easily reconstituted without agglutination, retains activity, and remains stable and active at storage at 4.degree. C.

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 consistent 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 method of specimen treatment preparatory to conducting an immunoassay is disclosed whereby a microbial protein is solubilized by a detergent at elevated temperatures and in the presence of an alkali or alkaline earth metal ion. At elevated temperatures, the detergent is soluble. However, at lower temperatures, the presence of the metal ion renders the detergent insoluble so that it is prevented from interacting in the immunoassay procedure. A specific application is in the solubilization of the principal outer membrane protein of Chlamydia trachomatis.

Abstract: A reagent for blood analysis comprises, as a lysing reagent for leukocyte count, tetradecyltrimethylammonium bromide and/or hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, and citric acid. This reagent is characterized by showing three-peaks fractionation of leukocytes in measuring by means of an automatic blood-analysis instrument. The lysing reagent is used together with a diluent comprising boric acid buffer solution, ethylenediaminetetraacetic acid and (2-pyridylthio-1-oxide) sodium.

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: Lysing reagents for use in flow cytometry instruments. Lysing reagents suitable for lysing red blood cells are provided thereby permitting 3-part differential counting of white blood cells. The reagents comprise a leukoprotective agent for preserving the lymphocyte cellular integrity during analysis, and buffers adjusted to provide the correct pH environment for optimal lysis and activity. Preferred embodiments will additionally incorporate non-ionic preservatives in very low concentrations.

Abstract: A reagent for blood analysis comprises, as a lysing reagent for leukocyte count, tetradecyltrimethylammonium bromide and/or hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, and citric acid. This reagent is characterized by showing three-peaks fractionation of leukocytes in measuring by means of an automatic blood-analysis instrument. The lysing reagent is used together with a diluent comprising boric acid buffer solution, ethylenediaminetetraacetic acid and (2-pyridylthio-1-oxide) sodium.

Abstract: A means of selectively lysing leukocytes but not bacteria is described. This technique is useful in conjunction with a reduction analysis to provide a rapid interference-free determination of either leukocytes or bacteria in clinical samples. The method is adaptable to a solution or dry element mode.

Abstract: Compositions and methods are provided for clarifying and partitioning aqueous lipid-containing specimens or samples such as lipemic serum and plasma. The compositions contain zwitterionic surfactant and water-immiscible organic solvent for lipids. The components of the compositions are selected such that they are compatible in vitro and, when constituted with aqueous specimens, do not interfere with biological or chemical activity of endogenous and exogenous analytes present in the respective specimens. The methods serve to partition the specimens into discrete aqueous and non-aqueous phases. The phases in turn can be individually assayed with respect to any of various analytes, for diagnostic or other purposes.

Abstract: Disclosed is a novel, 2 component Giemsa stain. The stain comprises a first component which is an aqueous solution of methylene blue, Azure B and a preservative and a second component which is an acetone/dimethyl formamide/water solvent system containing the sodium salt of eosin Y and a buffer. The Giemsa stain effect is obtained by first fixing a blood slide with methanol and then applying the freshly mixed first and second components of the stain. The slide is then rinsed and dried to prepare it for examination.

Abstract: A process for the preparation of a glucose-free glycosylated hemoglobin standard in which hemoglobin with a known content of glycosylated hemoglobin HbA.sub.Ia+b+c is converted to cyanmethemoglobin by means of a K.sub.3 (FeCN).sub.6 /KCN solution, stabilized with a sodium phosphate-cyanide buffer and preserved by lyophilizing at -40.degree. C. with a subsequent increase in temperature to -20.degree. C. under a high vacuum and stored at this temperature with the exclusion of light, whereupon the glucose-free glycosylated hemoglobin standard may be reconstituted by the addition of an aqueous medium.

Abstract: A hematology control is disclosed which is useful for clinical hematology procedures and, in particular, mean corpuscular volume (MCV) determinations. The hematology control comprises an aqueous suspension of red blood cells in which varying levels of MCV are provided by applying to the red cell component, after light treatment with aldehyde, an osmotic pressure that is directly proportional to the desired red blood cell size.

Abstract: A rapid one step, one reagent method is disclosed for the isovolumetric sphering and fixing of whole blood erythrocytes.

Abstract: An aqueous solution for suspending and storing cells, especially erythrocytes, and containing sodium chloride, glucose or fructose, adenine, and a sugar alcohol, the sugar alcohol being sorbitol or xylitol is employed to further improve the storage time and hence the survival rate of the cells and even reduce the hemolysis rate of erythrocytes in packed red blood cells.

Abstract: An improved reagent provides combined diluting and lysing of whole blood for use in instruments performing electronic blood cell counting and hemoglobin determination. The reagent prevents platelet aggregation and improves the accuracy of the white blood cell count.

Abstract: A method and reagent system is described for differential determination of more that one class of leukocyte populations, using an automatic blood cell analyzer. The reagent system includes a blood diluent and stromatolyzing reagent. The blood diluent is an osmotically balanced aqueous solution of ingredients for maintaining erythrocyte morphology, blood cell stabilizing, buffering and bacteriostatic action. The stromatolyzing reagent is a mixture of an aqueous solution of quaternary ammonium salts, a chromagen forming agent and an additive which is a non-cationic surfactant. The quaternary ammonium salts, with the additive, serve the purpose of positioning, relative to one another and a volume reference point, the lymphoid and myeloid populations. The additive also acts to prevent or to reduce the amount of protein deposit in the sensing orifices of the analyzer, which deposit tends to accumulate from the cell debris resulting from blood cell stromatolyzation.

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: The present invention provides a reagent for the precipitation of apo-B-containing lipoproteins, wherein it comprises 0.2 to 3 grams per liter of phosphotungstic acid and more than 2 mmols per liter of magnesium ions in aqueous solution.The present invention also provides a process for the preparation of this reagent and a process for the precipitation of apo-B-containing lipoproteins using this reagent.

Abstract: A method for eliminating turbidity in a biological fluid by combining said fluid with a surfactant and an enzyme is disclosed as well as a diagnostic reagent formulation for that purpose.

Abstract: Hematologic control and calibration standards are disclosed which are essentially plasma-free. These controls are prepared by the suspension of red blood cells in an appropriate buffer containing a stabilization effective amount of disaccharides, and other optional ingredients. Control and calibration standards prepared in the foregoing manner are suitable in the control and calibration of hematology analyzers for the following parameters: white cell count, red cell count, hemoglobin, hematocrit and the common derived parameters (i.e., mean cell volume, mean cell hemoglobin and mean cell hemoglobin concentration). The addition of platelets to the foregoing suspensions is also contemplated to provide a control for platelet parameters.

Abstract: The present invention provides a process for the direct turbidimetric determination of .beta.-lipoproteins (LDL) in body fluids by precipitation with polyanions and divalent cations, wherein the precipitation is carried out in the presence of a complex former at a pH value of from 7 to 9.The present invention also provides a reagent for the direct turbidimetric determination of .beta.-lipoproteins (LDL) in body fluids, comprising a polyanion, a salt of a divalent metal, a complex former and a substance buffering at pH 7 to 9.

Abstract: A method and reagent system is described for differential determination of three-populations of leukocytes (lymphocyte, monocyte and granulocyte), using an automatic counting system. The reagent system includes a blood diluent and lysing reagent. The blood diluent is an osmotically balanced aqueous solution of ingredients at a preselected pH for maintaining erythrocyte morphology, blood cell stabilizing, buffering and bacteriostatic action. The lysing reagent is a mixture of an aqueous solution of quaternary ammonium salts, which lysing reagent is added to the diluted blood under more mild conditions of concentration and at a slower rate than is current practice in order to obtain an unexpected volumetric modification of at least one of the three-populations of leukocytes, whereby volumetric differential analysis can be accomplished.

Abstract: A reference fluid for the calibration and control of blood gas instruments is comprised of substantially pure stroma-free hemoglobin solution, a buffering agent, a source of bicarbonate ion and predetermined amounts of gases found in in vivo blood.

Abstract: A control material for use in the determination of glycosylated and total hemoglobin, and a method of preparing the same, are disclosed. The control is prepared by the steps of hemolyzing red blood cells, preferably in the presence of a detergent, followed by removal of stroma and lipids from the hemoglobin with an organic solvent such as toluene in the presence of a polyhydroxy compound such as sucrose. A hemoglobin-rich fraction is separated from the resulting mixture and dialyzed against a solution of a polyhydroxy compound. The dialysate may be lyophilized to provide a stable, dry product suitable for reconstitution.

Abstract: A process for the determination of glycosilated hemoglobin in a blood sample comprises liberating glycosilated and non-glycosilated hemoglobin from the erythrocytes by chemical or physical treatment; converting, if desired, the hemoglobin into methemoglobin, and thereafter differentiating the glycosilated and non-glycosilated hemoglobin portion using its reaction with haptoglobin, and determining the glycosilated and/or the non-glycosilated hemoglobin portion.The present invention also provides a reagent for the determination of glycosilated hemoglobin in a blood sample, as well as a reagent for the differentiation of glycosilated and non-glycosilated hemoglobin, comprising haptoglobin.

Abstract: A process for the detection of antibodies in a test sample is described. This process involves:(a) preparing an essentially isotonic and low ionic strength suspension comprising said sample and erythrocytes in net negatively-charged form;(b) maintaining said suspension for at least 30 seconds;(c) combining said suspension with an amount of a solution of polymer effective for agglutination of said erythrocytes;(d) separating the resultant agglutinates of polymer and erythrocytes from supernatant of said suspension;(e) dispersing said agglutinates in a hypertonic salt solution having an essentially neutral pH; and(f) monitoring the dispersed agglutinates for dissociation of erythrocytes.This process permits rapid detection of antibodies with great ease. Their presence is indicated by persistence of the agglutinates in the dispersion. The antigen which reacts with antibody may be native to the erythrocytes, or may be unrelated to erythrocytes but artificially coupled to those cells.

Abstract: An acidic solution of glycine and a fatty acid of 3 to 12 carbon atoms provides an improved solution for cleaning and storing blood dialyzers and other separation devices, particularly those intended for contact with blood after they have once been used.

Abstract: This invention utilizes for stabilization of platelets a combination of iodoacetamide and an iminodiacetic acid or salt thereof, together with a compatible bacteriostatic agent, in an aqueous electrolytic solution which is maintained at a preselected range of pH and osmolality.In a preferred formulation, the stabilizing solution contains iodoacetamide, N-(2-acetamido)iminodiacetic acid and sodium penicillin. Ethylenediaminetetraacetic acid, or salts thereof, are optionally present as an additional ingredient.

Abstract: A method for the removal of hormones from whole human serum which comprises: contacting, at a pressure higher than 1 psi the serum with a composite sheet, the composite sheet comprising a matrix of self-bonding fibers having interdispersed therein carbon particles, such that better than 90% of the carbon particles have an average diameter less than about 50 microns; and recovering a whole human serum having substantially undetectable amounts of hormones. The method is particularly useful for the removal of thyroid hormones.

Abstract: Biological cell compositions are stabilized to preserve aldehyde functionality by formation of acetal, particularly cyclic acetal, primarily in order to prevent cell-to-cell crosslinking. The stabilized biological cells are particularly useful as human blood particle analogs in reference reagents employed in electronic hematology testing instrumentation.A process for preparing the acetal-stabilized biological cells employs reaction of polyaldehyde-treated biological cells with alcohol, preferably including 1,2 dialcohol, under acidic conditions; thereafter, the resulting product solution is adjusted to basic condition, stabilizing the acetal formation on the biological cells.

Abstract: Stabilized reference control and calibrator compositions for determining multiple platelet parameters in stand alone platelet controls and whole blood reference controls are prepared from platelets stabilized with a fixative-stabilizing composition containing glutaraldehyde and a non-ionic surfactant which is a mixture of ethoxylates of certain isomeric linear alcohols.

Abstract: A low ionic strength suspending medium for immunologic reactions which includes a salt solution, a buffer, gelatin, albumin, and an organic solute to control osmolality.

Abstract: A process for dissolving chylomicrons in an aqueous medium composed of (a) at least one polyethylene glycol ether of an alkanol or alkylaryl alcohol with a branched alkane chain and with an HLB value of 12 to 14, and (b) at least one secondary alkyl sulphonate containing 10 to 20 carbon atoms in the molecule, and optionally (c) an alkali metal p-toluenesulphonate; andthe agent formed by the combination of (a), (b) and optionally (c).

Abstract: A labile, organic reagent, which is unstable in aqueous media and stable in a nonaqueous media, is stabilized by dissolving the organic reagent in a water-miscible, organic solvent which is liquid at room temperature and which is nondegradatively reactive with the organic reagent to form a solution of the organic reagent in the organic solvent. At least 1% of an inert, high-surface area particulate desiccant is added to the solution for entrapping water with the desiccant so that the residual water content of the solution is below about 0.5%. The desiccant can be removed from the solution before sealing it. More than one organic reagent can be added to the solvent, and a solubilizing agent for the organic reagent can be used.