Abstract: Erythrocytes from a vertebrate animal other than a human that have been size reduced and treated with a fixing agent by conventional methods to resemble human platelets are further treated to achieve a size distribution that is detected in a consistent manner by different methodologies of blood cell counting. The further treatment includes heating to a denaturing temperature followed by a second treatment with a fixing agent. The resulting cells are useful as controls for calibrating and checking the accuracy of automated blood cell counting equipment.

Abstract: The present invention provides a method for preparing cells for use in a hematology blood control. The preparation steps, namely the use of cross-linking agents such as aldehydes, involve a step-wise process starting with very low concentrations of a cross-linking agent. Successive fixations involve an increase in the concentration of cross-linking agent.

Abstract: A hematology control composition and method of making the composition is provided. The control employs a plurality of components including a synthetic plasma component, a red blood cell component, a platelet component and a leukocyte component. The leukocyte component includes at least one subpopulation having particles derived from other than white blood cells.

Abstract: The present invention provides a method for preparing cells for use in a hematology blood control. The preparation steps, namely the use of cross-linking agents such as aldehydes, involve a step-wise process starting with very low concentrations of a cross-linking agent. Successive fixations involve an increase in the concentration of cross-linking agent.

Abstract: The control of the present invention involves a gentle chemical removal of red cells, leaving an intact white cell preparation. The preservation steps, namely the use of cross-linking agents as aldehydes, involve a step-wise process starting with very low concentrations of a cross-linking agent. The fixation part of the process outlined in this disclosure has also been applied to non-mammalian blood cells and therefor would appear to be a universal procedure for preparing all types of vertebrate blood cells.

Abstract: A hematology control composition and method of making the composition is provided. The control employs a plurality of components including a synthetic plasma component, a red blood cell component, a platelet component and a leukocyte component. The leukocyte component includes at least one subpopulation having particles derived from other than white blood cells.

Abstract: The control of the present invention involves a gentle chemical removal of red cells, leaving an intact white cell preparation. The preservation steps, namely the use of cross-linking agents as aldehydes, involve a step-wise process starting with very low concentrations of a cross-linking agent. The fixation part of the process outlined in this disclosure has also been applied to non-mammalian blood cells and therefor would appear to be a universal procedure for preparing all types of vertebrate blood cells.

Abstract: A composition and a method for using the composition for manipulating the electronic and optical properties of biological particles are disclosed. The composition generally has a hypotonic buffering solution, a polyhydroxy alcohol, a stabilizing agent, and, in some applications, a non-ionic surfactant. By varying the relative concentrations of these components and by adjusting the timing of their combination and interaction, the composition and method allow for the alteration of the electronic and optical properties of the particles to achieve target values for the properties. In one particularly advantageous application, the composition and method of the invention allow for the creation of selected analogs for the subpopulations of human leukocytes from a single biological particle for use as a control product in differentiating particle analyzers.

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: Improved reagents and methods for obtaining distinct volumetric differentiation of platelets, erythocytes and certain leukocyute subpopulations are disclosed. 1,3-dimethylurea is disclosed as a cell stabilizing agent for use in the blood diluent reagent. A hematology analyzer detergent is described wherein the addition of a wetting agent to the diluent of the instant invention provides the necessary attributes of an automatic analyzer detergent. The lysing reagent exploits the selective and intrinsically gentle lytic qualities of the dodecyl quaternary ammonium salt. The improved method modifies the leukocytes so that the frequent lymphocyte and neutrophil subpopulations are well separated on a volume scale, permitting quantitative evaluation of infrequent and rare leukocyte subpopulations as well as improved enumeration of the lymphocytes and neutrophils.