Abstract: The invention concerns a staining reagent for the determination of blood cells, in particular reticulocytes, which contains a stain capable of labelling cells after incubation, as well as an additive which is able to encourage penetration of the stain into the cells, this additive being chosen from an ionophoric compound, a detergent and mixtures thereof.

Abstract: A dual purpose tissue fixative is described. The fixative comprises a cross-linking aldehyde, alcohol, a chelating agent and a non-amine buffer. More particularly, the tissue fixative comprises 0.1-2% w/v formaldehyde, 45-90% w/w alcohol, 1-10 mM of a chelating agent and 1-50 mM of a non-nitrogen buffer. The tissue fixative permits the recovery of high molecular weight DNA and RNA from the tissue sample for molecular genetic analysis. The tissue fixative also preserves the morphology and immunogenicity of the tissue allowing for pathology analysis. The tissue fixative is compared to 95% alcohol and a standard fixative as 10% BNF.

Abstract: A reagent for measurement of leukocytes and hemoglobin concentration in the blood includes a cationic surfactant in an amount sufficient to lyse erythrocytes and denature hemoglobin, at least one of the following hemoglobin stabilizers:(a) sulfosalicylic acid, or its salt, in an amount effective for promoting the conversion of hemoglobin into methemoglobin,(b) 0.2 to 10.0 g/L of a water-soluble chelating agent having a nitrogen atom and a carboxyl group, and(c) piperazine, or its salt, in an amount effective for promoting the conversion of hemoglobin into methemoglobin, anda buffer for maintaining pH at 4 to 6.

Abstract: A hematological sample is treated with a hemolytic agent that maintains immature leukocytes in a viable state and damages other leukocytes. The damaged leukocytes are stained with a fluorochrome which can stain damaged cells. At least one kind of scattered light and at least one kind of fluorescence of the treated and stained blood cells are measured to classify and count leukocytes based on the intensities of the scattered light and the fluorescence. Highly precise measurement of immature leukocytes and simultaneous classification and counting of normal leukocytes are achieved.

Abstract: Cyanide-free reagents for the determination of hemoglobin and leukocytes present in a blood sample contain an aqueous solution of at least one quaternary ammonium salt, preferably selected from the group of alkyltrimethylammonium salts, alkyldimethylbenzylammonium salts or alkylpyridium salts consisting of tetradecyltrimethyl ammonium bromide (TTAB), dodecyltrimethyl ammonium chloride, cetyltrimethyl ammonium bromide, hexadecyltrimethyl ammonium bromide and benzalkonium chlorides, and hydroxylamine salts, especially hydrochloride, sulfate and phosphates and other acid salts. The method involves mixing the reagent with a diluent- diluted blood sample, presenting it to an absorbance spectrophotometer and measuring the resulting optical density as an indicator of hemoglobin concentration. This cyanide-free reagent could be used solely for hemoglobin determinations, or , it can also be used in leukocyte counting and sizing using hematology instrumentation.

Abstract: An improved isotonic multipurpose blood diluent, and a method for use of this diluent is provided. The diluent is especially suitable for electronic enumeration and sizing of blood cells, determination of hemoglobin parameters and differentiation of leukocyte subpopulations in a single blood cell sample using a cyanide free lytic reagent. The diluent finds particular applicability over wide operating temperatures.

Abstract: An assay and sample mixture for the enumeration of fluorescently stained target components of a whole blood sample by an imaging instrument. The sample preparation method ensures that the amount of target components per unit of volume of the whole blood sample is preserved by elimination of certain non-quantitative preparation steps while producing an even hematocrit layer within a scan capillary. Typical target components include white blood cells that express certain surface antigens, such as CD-4 and CD-8 proteins. To inhibit aggregation of the red blood cells, a reagent is added to an aliquot of whole blood sample. The aliquot of whole blood is mixed and with a preselected amount of a fluorescent dye and ligand complex which tags the target components.

Abstract: A reagent and a method for classifying leukocytes with a flow cytometer by means of optical measurements on fluorochrome-stained blood cells are included.The reagent and the method are useful in the practice of clinical testing.

Abstract: Disclosed is a method for pretreating heat stable proteins derived from a rendered animal material prior to performing an assay for their presence comprising (a) preparing a protein containing extract of the material, (b) removing substantially all or part of the gelatin from the extract and (c) concentrating the remaining protein such that it tests positive for protein by immunoassay at a dilution of greater than 1 in 6,000.

Abstract: A reagent for analyzing solid components in urine comprising: (i) a buffer agent for maintaining pH at 5.0 to 9.0, (ii) an osmotic pressure compensating agent for maintaining osmotic pressure at 100 mOsm/kg to 600 mOsm/kg, (iii) a first dye which is a condensed benzene derivative, (iv) a second fluorescent dye capable of staining a damaged cell, and (v) a chelating agent.

Abstract: A cyanide-free lytic reagent composition and method for measuring the total hemoglobin concentration in a blood sample, for counting the number of leukocytes and for deferential counting of leukocyte subpopulations are described. The cyanide-free lytic reagent composition cotains a quaternary ammonium salt or a pyridinium salt to lyse erythrocytes and release hemoglobin, and an organic ligand including triazole and its derivatives, tetrazole and its derivatives, alkaline metal salts of oxonic acid, melamine, aniline-2-sulfonic acid, quinaldic acid, 2-amino-1,3,4-thiadiazole, triazine and its derivatives, urazole, DL-pipecolinic acid, isonicotinamide, anthranilonitrile, 6-aza-2-thiothymine, 3-(2-thienyl)acrylic acid, benzoic acid and alkali metal and ammonium salts of benzoic acid, and pyrazine and its derivatives to form a stable chromogen with hemoglobin, and a salt to adjust conductivity of the reagent for impedance measurement.

Abstract: A method is provided for differentiating leukocyte subpopulations, immunophenotyping of lymphocytes and counting white blood cells. The method preserves leukocyte morphology and surface markers without using fixatives. In addition, the method finds utility in determination of hemoglobin concentration without using cyanide. The stable hemoglobin chromogen formed is measured at approximately 540 nm.

Abstract: A cyanide-free method and reagent for determining the concentration of total hemoglobin in a whole blood sample accurately in less than 10 seconds including a ligand selected from the group consisting of imidiazole, imidazole derivatives, N-hydroxyacetamide, N-hydroxyl amine, pyridine, oxazole, thiazole, pyrazole, pyrimidine, purine, quinoline, and isoquinoline, and a surfactant with strong erythrolytic capability selected from the group consisting of lauryl dimethylamine oxide and octylphenoxy polyethoxyethanol. The reagent pH is adjusted to about 11 to about 14. Rapid mixing of the reagent with a blood sample leads to the formation of a stable chromogen whose absorbance can be measured between 540 and 550 nm. The cyanide-free reagent is ideal for use on an automated high through-put clinical hematology analyzer.

Abstract: Hematology reference control cells and method of manufacture. The invention relates to the methods of preparing stable white blood cell ("WBC") and nucleated red blood cell ("NRBC") fractions and the hematology control reagents containing such stablized cells for primary use on a multi-angle light scatter based hematology instrument.

Abstract: The invention describes an improved stable reagent composition and method for the determination of hemoglobin (Hb) using whole blood samples and automated hematology analyzers. The Hb reagent contains an inorganic cyanide salt, at least one surfactant and a base and has a final pH of about 10.0 to about 11.2, preferably about 10.4 to about 11.2 or less and more preferably about 10.8 to about 11.2 or less. This reagent is intended for use as a universal Hb determination reagent for all of the instruments in the aforementioned series and will provide accurate and precise results without accompanying interference from elevated numbers of white blood cells, especially as found in abnormal blood specimens, and without system-to-system variation in the results obtained.

Abstract: A stabilized cell suspension is prepared by treating the cell suspension with a solution of a heavy metal compound, which has been aged at pH 6.5-7.5 prior to use to allow a precipitate to form, removing the precipitate from the heavy metal solution, mixing the aged heavy metal solution with the cell suspension to form a first mixture, and mixing the first mixture with a paraformaldehyde solution to form a stabilized cell suspension which is still capable of lysis.

Abstract: A method and composition for fixing and stabilizing tissues, cells, and cell components such that the antigenic sites and nucleic acids are preserved is provided. The fixative employs a formaldehyde donor that is non-toxic, non-flammable, and that stabilizes the cell with minimal damage to and alteration of the cell morphology. The cell antigenic sites are left intact so that studies with monoclonal antibodies may be conducted. Vaccines and related immunotherapeutic methods utilizing antigens stabilized by the fixative of the present invention are also provided. Also disclosed is a method for developing a positive control for test reagents and for test instrumentation.

Abstract: A lytic reagent composition is provided which selectively stromatolyses red blood cells in a blood sample. In addition, a lytic reagent system is provided which enable the differentiation of at least two subpopulations of leukocytes. A method for using the lytic reagent system is also provided. Still further, the lytic reagent system find use in the determination of the hemoglobin in the blood. The lytic reagent system utilizes an ethoxylated long chain compound based lysis reagent with an acid and a solubilizer, and a hypertonic, alkaline, stabilizing reagent. The system and analysis method maintains the cellular morphology of the leukocytes and can be used to analyze normal and abnormal blood samples, fresh and aged blood, human and non-human animal blood samples, as well as other fluid samples such as bone marrow.

Abstract: A reagent composition which does not contain cyanide ions and a method for measuring hemoglobin concentration in a blood sample. In addition, the reagent composition can be used to measure hemoglobin concentration and differentiate at least two subpopulations of leukocytes from the same reaction product of the reagent composition and a blood sample. The reagent composition comprises at least one lysing agent selected from the group consisting of a quaternary ammonium salt, a pyridinium salt, and combinations thereof, in an amount effective to adequately lyse the erythrocytes and elute the hemoglobin, an antioxidant in an amount effective to convert the released hemoglobin into to a hemochromogen. The pH can be adjusting with a pH agent to provide a pH ranging from 5 to 11.5.

Abstract: The invention describes improved methods and reagent compositions employed therein to determine the existence of blood disorders such as hemolytic anemias in a blood sample obtained from an individual. The methods are preferably carried out on an automated flow cytometer and encompass determining if the individual's red blood cells have undergone a loss of membrane surface area by providing measurements of the surface area and the sphericity of the red blood cells in a whole blood sample as a function of osmolality. The method and reagent compositions used therein provide for the first time accurate measurements of the surface areas of both the mature red blood cell and the reticulocyte populations in a whole blood sample. The method and reagents of the invention promise to shed new insights into reticulocyte membrane remodeling in various red cell disorders.

Abstract: A method for differentiating and isolating sub-populations of leucocytes in a blood sample involved treating the sample with polyoxyethylene 9-lauryl ether. This method is suitable for isolating basophil granulocytes when it is conducted in an acid medium.

Abstract: A compound represented by the formula (I): ##STR1## wherein R.sub.1 is hydrogen atom or a lower alkyl group; R.sub.2 and R.sub.3 are independently hydrogen atom, a lower alkyl group or a lower alkoxy groups; R.sub.4 is hydrogen atom, an acyl group or a lower alkyl group; R.sub.5 is hydrogen atom or an optionally substituted lower alkyl group; Z is sulfur atom, oxygen atom or carbon atom substituted with a lower alkyl group; n is 1 or 2; and X.sup.- is an anion.

Abstract: This invention relates to a lytic reagent and a method of using the lytic reagent for automatically determining leukocyte subpopulations in blood. More specifically, the new lytic reagent lyses red blood cells and affects the eosinophils which enables the differentiation of at least one subpopulation of leukocytes. The lytic reagent is an acidic, hypertonic aqueous solution containing alkali metal salt of alkyl sulfite, an eosinolytic agent, a nonionic surfactant and a physiological salt. When used in combination with a second lytic reagent system, one is able to obtain at least a five part differential of leukocytes using DC and RF measurements.

Abstract: A method of staining cellular material where a sample containing the cellular material is stained with a stain solution containing a cyanine dye excitable by infrared rays to contrast its nuclear material from its cytoplasmic material.

Abstract: A process and a reagent for the specific and direct determination of the LDL-fraction in the presence of other serum lipoproteins by adding a polymeric LDL-aggregating agent, followed by direct turbidimetric measurement of the LDL aggregate. Preferred are polymers which have a comb or brush type structure with the side groups having acid character, such as branched alkane sulfonic acids.

Abstract: A lytic reagent composition is provided which selectively stromatolyses red blood cells in a blood sample. In addition, a lytic reagent system is provided which enables the differentiation of at least three subpopulations of leukocytes. A method for using the lytic reagent system is also provided. Still further, the lytic reagent system finds use in the determination of the hemoglobin in the blood. The lytic reagent system utilizes an alkyl sulfate, polyoxyethylene based surfactant and acid with a hypertonic, alkaline, stabilizing reagent. The system and analysis method maintains the cellular morphology of the leukocytes and can be used to analyze normal and abnormal blood samples, fresh and aged blood, human and non-human animal blood samples.

Abstract: A method for quantitatively determining cholesterol in high density lipoproteins, in which, prior to the determination of cholesterol by an enzymatic method, a surfactant and a substance which forms a complex with lipoproteins other than high density lipoproteins are added to a sample containing lipoproteins.The method does not require any pretreatments such as centrifugal separation. With a simple operation, cholesterol in HDLs can be measured effectively. Also, this method can be adopted in a variety of automated analyzers, and thus is very useful in the field of clinical assays.

Abstract: A method and reagent for the simultaneous or independent enumeration of reticulocytes in a whole blood sample, without the need to separately incubate the sample and reagent. The reagent contains a reticulocyte staining amount of an unsymmetrical cyanine dye, from about 40 mM to about 60 mM of a buffer selected from the group consisting of imidazole, Tris and Bis-Tris and a dye stabilizing amount of a non-ionic surfactant selected from the group consisting of N, N-bis?3-D-Glucon-amidopropyl! cholamide and a polyoxypropylene-polyoxyethylene block copolymer. The reagent has a pH from about 6.8 to about 7.2 and an osmolarity adjusted to about 280 to about 310 mosm/l with a mono-, or di-, valent alkali salt selected from the group consisting of NaCl, KCl, LiCl, CaCl.sub.2, MgCl.sub.2 and ZnCl.sub.2. The method utilizes the reagent in a no incubation process that also allows for the simultaneous determination of CBC as well as reticulocyte counts and maturity indices.

Abstract: A method of preserving sensitive biological dispersions, suspensions, emulsions and solutions by forming stable foams from fluid materials to be dehydrated, as an aid both to the drying of one or more biologically active substrates in the fluid and as an aid in preparing an easily divisible dried product suitable for further commercial use. The stable foams are formed by partially removing the water to form a viscous liquid and by further subjecting the reduced liquid to vacuum, to cause it to "boil" during further drying at temperatures substantially lower than 100 degrees C. In other words, reduced pressure is applied to viscous solutions or suspensions of biologically active materials to cause the solutions or suspensions to foam during boiling, and during the foaming process further solvent removal causes the ultimate production of a stable open-cell or closed-cell foam.

Abstract: A cyanide-free lytic reagent composition and method for measuring the total hemoglobin concentration in a blood sample, for counting the number of leukocytes and for deferential counting of three leukocyte subpopulations including lymphocytes, monocytes, and granulocytes are described. The cyanide-free lytic reagent composition includes a hemolytic surfactant chosen from quaternary ammonium salts, pyridinium salts, organic phosphate esters, and alkyl sulfonates to lyse erythrocytes and release hemoglobin, and an organic ligand chosen from triazole and its derivatives, tetrazole and its derivatives, alkaline metal salts of oxonic acid, melamine, aniline-2-sulfonic acid, quinaldic acid, 2-amino-1,3,4-thiadiazole, triazine and its derivatives, urazole, DL-pipecolinic acid. isonicotinamide, anthranilonitrile, 6-aza-2-thiothymine, adenine, 3-(2-thienyl)acrylic acid, benzoic acid and alkali metal and ammonium salts of benzoic acid, and pyrazine and its derivatives to form a stable chromogen with hemoglobin.

Abstract: The invention relates to a plasma which can be used as a calibrator in coagulation tests which detect the degradation of factor V by activated protein C, to the preparation of such a plasma and to its use.

Abstract: A leukocyte classification reagent comprising at least one surface active agent selected from the group consisting of anionic active agents and amphoteric active agents lyses erythrocytes within a short period of time when added to a blood sample but does not cause damage on leukocytes for a certain period of time keeping their original state or close to the original state so that leukocytes can be classified directly into four groups, namely lymphocyte, monocyte, neutrophil and eosinophil, by measuring forward scattering and side-way scattering by a flow cytometer after lysis of erythrocytes.

Abstract: A process for the elimination of labile glycohaemoglobin from a sample comprises adding to the sample a reagent comprising a temperature dependent buffer having a pH/temperature coefficient of -0.011 or less, and a method for measuring the concentration of stable glycohaemoglobin in sample containing stable and labile glycohaemoglobin fractions.

Abstract: The present invention is directed to an in vitro aqueous composition comprising a drug, preferably tacrolimus or rapamycin, having enhanced stability. The invention utilizes a binding protein, preferably FKBP, to stabilize the drug in an aqueous matrix.

Abstract: Whole blood is mixed with a reticulocyte reagent system that has a reticulocyte staining reagent and a diluent reagent, used in combination. This mixture is incubated at room temperature for between about 15 minutes to about 4 hours. The incubated mixture is then analyzed and the light scattering properties of the cells are detected, collected, differentiated and quantitized. Data gathering includes, at least, 10 and 90 degree light scatter detection.

Abstract: A lytic reagent composition and a kit of a lytic reagent system are disclosed for the rapid isolation, identification and/or analysis of at least five subpopulations of leukocytes from a whole blood sample. The composition and system have 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. The lytic reagent composition of this invention comprises saponin and a carboxylic acid of the formula RCOOH wherein R is H or a C.sub.1-3 aliphatic hydrocarbon radial optionally substituted by one or more carbonyl and/or hydroxy groups. The kit of a lytic reagent system comprises the lytic reagent composition and a quench reagent.

Abstract: A process and apparatus for preparing blood for analysis of white blood cells involves:preparing a mixture made up of blood and a lysing agent,emitting luminous radiation in the direction of the mixture,receiving the light emitted through the mixture,comparing the quantity of light received at a pre-determined threshold, the process of erythrolysis, being complete when the quantity of light corresponds to the threshold and,neutralizing the action of the lysing agent when erythrolysis is completed by the addition of an appropriate reagent.

Abstract: A method is presented for selective stimulation of fetal lymphocytes to divide in culture after treatment of mixed adult-fetal blood samples. This method is particularly useful for diagnosing genetic abnormalities of a fetus using fetal cells from a maternal blood sample. The method consists of preferential destruction of maternal lymphocyte response to low concentrations of mitotic stimulants which results in a relative increase in the number of responding fetal cells in mixed adult-fetal blood samples. In the preferred embodiment of the invention, blood samples from pregnant women are processed by the described methodology, in particular, the erythrocytes are removed from the maternal sample by centrifugation, filtration or preferential lysis with ammonium bicarbonate, the suspension is then subjected to an osmotic shock and exposed to mitotic stimulants in culture, and cells in mitosis are harvested for chromosome analysis.

Abstract: The present invention is drawn to an immunoassay capable of the rapid detection of a variety of test substances that may be present in a test sample. One feature of the invention is that extraction or isolation of the test substance occurs simultaneously with the formation of the primary antigen-test substance complex. The primary antigen-test substance complex is then captured in a solid phase format having a plurality of interstitial spaces which facilitate rapid and efficient detection. The immunoassay of the present invention works over a wide range of environmental conditions and is simple enough to be used in the absence of laboratory facilities.

Abstract: A method and reagent for the simultaneous or independent enumeration of reticulocytes in a whole blood sample, without the need to separately incubate the sample and reagent. The reagent contains a reticulocyte staining amount of an unsymmetrical cyanine dye, from about 40 mM to about 60 mM of a buffer selected from the group consisting of imidazole, Tris and Bis-Tris and a dye stabilizing amount of a non-ionic surfactant selected from the group consisting of N, N-bis?3-D-Glucon-amidopropyl! cholamide and a polyoxypropylene-polyoxyethylene block copolymer. The reagent has a pH from about 6.8 to about 7.2 and an osmolarity adjusted to about 280 to about 310 mOsm/l with a mono-, or di-, valent alkali salt selected from the group consisting of NaCl, KCl, LiCl, CaCl.sub.2, MgCl.sub.2 and ZnCl.sub.2. The method utilizes the reagent in a no incubation process that also allows for the simultaneous determination of CBC as well as reticulocyte counts and maturity indices.

Abstract: A lytic reagent composition is provided which selectively stromatolyses red blood cells in a blood sample. In addition, a lytic reagent system is provided which enable the differentiation of at least two subpopulations of leukocytes. A method for using the lytic reagent system is also provided. Still further, the lytic reagent system find use in the determination of the hemoglobin in the blood. The lytic reagent system utilizes an ethoxylated long chain compound based lysis reagent with an acid and a hypertonic, alkaline, stabilizing reagent. The system and analysis method maintains the cellular morphology of the leukocytes and can be used to analyze normal and abnormal blood samples, fresh and aged blood, human and non-human animal blood samples, as well as other fluid samples such as bone marrow.

Abstract: A method for classifying and counting leukocytes which includes the steps of (i) adding a first reagent used for classifying leukocytes into four groups which contains, (a) at least one ionic surfactant in a sufficient amount to lyse erythrocytes and to damage a part of cell membrane of leukocytes, (b) at least one organic compound having an anionic group in a sufficient amount to bond with a cationic component present in leukocytes to give morphological differences between leukocytes, (c) a nonionic surfactant, and (d) a buffer for adjusting pH, to a part of a blood sample to determine information on the cell size and morphological features in order to classify leukocytes into four groups consisting of three groups corresponding to lymphocytes, mononuclear cells and eosinophils and one group corresponding to neutrophils and basophils; (ii) adding a second reagent used for measuring basophils to another part of the blood sample to determine information on at least the cell size in order to classify basophils,

Abstract: Compositions, devices and methods for the detection of target microorganisms, such as by a visual immunoprecipitation assay, where the detection requires the migration of the target microorganisms (typically a target microorganism-antibody-detection reagent complex) along a lateral flow membrane of a diagnostic device. The present invention permits such detection by inhibiting the agglutination, or other aggregation, of target microorganisms (and particularly target microorganisms bound to an antibody-detection reagent) while the microorganisms are migrating along the lateral flow membrane.

Abstract: A multipurpose reagent system for rapid analysis of a whole blood sample allowing the determination of at least five classes of peripheral white blood cells, nucleated red blood cells, and lymphocyte immunophenotyping on automated hematology instrumentation. The multipurpose reagent system lyses red cells rapidly, while it concurrently fixes white cells and preserves surface antigens on lymphocytes. The multipurpose reagent system comprises from about 3 to 7 grams per liter of a non-quaternary ammonium salt, from about 0.04 to about 0.10 percent by volume of an aliphatic aldehyde with one to four carbons, from about 10 mM to about 20 mM of a non-phosphate buffer which is inert to the aliphatic aldehyde, and a sufficient amount of water to give a pH between 5.5 and 7.5 and an osmolality of between about 160 to about 310 mOsm per liter.

Abstract: The present invention provides an improved reagent composition and method to perform white blood cell differential counting and subpopulation analysis using both fresh and aged blood samples with accuracy and precision. The invention is particularly applicable for the analysis of aged blood samples that have been stored at room temperature for over a day, thereby allowing accurate and useful information to be obtained from samples that are normally considered to be suboptimal. The improved reagent composition and method are particularly related to the peroxidase method of white blood cell differential determinations. One aspect of the invention includes an improved aqueous reagent composition for carrying out the peroxidase method of differential counting.

Abstract: A process for determining the reticulocyte population in blood samples, which process includes the use of coriphosphine O to stain reticulocytes and which process is particularly suitable for detection by flow cytometry techniques.

Abstract: Methods for blood sample preparation using reagent compositions which include a zwitterionic surfactant for sphering of cells to eliminate orientational noise. When the reagent composition including a dye for staining a subset of cells is reacted with a blood sample, and the reaction mixture is passed through the sensing region of a flow cytometer, the light scattered and absorbed by each cell is measured, the stained cells can be distinguished from the unstained cells, and when the cells are reticulocytes and mature erythrocytes, respectively, the volume and hemoglobin concentration of each reticulocyte or erythrocyte, and the hemoglobin content, mean cell volume, mean corpuscular hemoglobin concentration, and mean cell hemoglobin of the reticulocytes or erythrocytes are calculated from the measured cell-by-cell volume and hemoglobin concentration.

Abstract: Detectably labelled annexines and compositions thereof are disclosed. Also disclosed are methods for diagnosing a disruption or activation of the hemostatic system or a prothrombotic state in an individual suspected of having a hemostatic disorder, by contacting the blood of said individual with an annexine, and detecting whether an annexine-platelet complex is formed.

Abstract: A reagent for analyzing leucocytes comprises (a) at least one ionic surfactant, being either a cationic or an amphoteric surfactant, in an amount sufficient for lysing erythrocytes and causing damage to a part of cell membranes of leucocytes; (b) at least one organic compound having a hydrophobic group and an acidic group which has a negative charge in an aqueous solution in an amount sufficient for a preserving leucocyte morphology by combining with a cationic component in leucocytes; (c) a nonionic surfactant; and (d) a buffer for adjusting pH.

Abstract: A cyanide-free method and reagent for determining the concentration of total hemoglobin in a whole blood sample accurately in less than 10 seconds comprising a ligand selected from the group consisting of imidiazole, imidazole derivatives, N-hydroxyacetamide, N-hydroxyl amine, pyridine, oxazole, thiazole, pyrazole, pyrimidine, purine, quinoline, and isoquinoline, and a surfactant with strong erythrolytic capability selected from the group consisting of lauryl dimethylamine oxide and octylphenoxy polyethoxyethanol. The reagent pH is adjusted to about 11 to about 14. Rapid mixing of the reagent with a blood sample leads to the formation of a stable chromogen whose absorbance can be measured between 540 and 550 nm. The cyanide-free reagent is ideal for use on an automated high through-put clinical hematology analyzer.