title: Outdated blood and redundant buffy-coats as sources for the preparation of multiparameter controls for Coulter-type (resistive-particle) hemocytometry.
abstract: Outdated, buffy-coat depleted, CPDA-1 blood and redundant buffy-coats were used as sources for the laboratory preparation of controls for Coulter-type (resistive-particle) hemocytometry. Deteriorated white blood cells and platelets and potentially interfering microaggregates with volumes not exceeding 400 fl are shown to be virtually completely removed by centrifugation and filtration. Addition of fixed red blood cells as white blood cell substitutes and of isolated, fixed platelets enable the preparation of multiparameter controls of short-to-medium-term stability. The availability of these simple, inexpensive controls can contribute significantly to optimal internal quality control in hemocytometry.
mesh_terms: D001771:Blood Banks; D001772:Blood Cell Count / Q000592:standards*; D001793:Blood Preservation; D004909:Erythrocyte Indices; D006801:Humans; D011786:Quality Control; D013997:Time Factors