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: 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: 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: An isotonic cleansing agent and method for its use in electronic instrumentation systems for determining hematological components of blood samples are described. The cleansing agent comprises an aqueous solution of a non-hemolytic polyoxyethylated alkylphenol detergent, dimethylolurea, and an isotonic and isoconductive saline base which is free of phosphates. The dimethylolurea serves as a cell stabilizer, and also acts as a germicidal agent, together with other added germicidal agents, particularly sodium 1-hydroxypyridine-2-thione.