[Demonstration of neutrophil leukocytes on blood smears by a modified colloidal iron reaction (author's transl)]

Using a modified colloidal iron reaction two positively reacting components in neutrophil leukocytes are discernible: 1. In neutrophils of unfixed smears the outer membrane or surface coat is stained. 2. After fixation with buffered formalin, formalin-sublimate or Helly's fluid a strongly reacting cytoplasmic component is demonstrable. After fixation with formalin-sublimate or Helly's fluid the latter has been proven to be sensitive against treatment with sialidase thus indicating the presence of sialic acid residues in neutrophil granulocytes.