3. =Basic double staining.= Saturated, watery methyl-green solution is mixed with alcoholic fuchsin.
The stain, which only requires a small fixation, is completed in a few minutes, and colours the nuclei green, the red blood corpuscles red, the protoplasm of the leucocytes fuchsin colour. It is therefore specially suited for demonstration preparations of lymphatic leukæmia.
4. Eosin-methylene blue mixtures, for example Chenzinsky's fluid:
Concentrated watery methylene blue solution 40 c.c. 1/2% eosin solution in 70% alcohol 20 c.c. Aqua dest. 40 c.c.
This fluid is fairly stable, but must always be filtered before use. It only requires a fixation of the specimen for five minutes in absolute alcohol. The staining takes 6-24 hours (in air-tight watch-glasses) at blood temperature. The nuclei and the mast cell granulations stain deep blue, malaria plasmodia light sky blue, red corpuscles and eosinophil granules a fine red.
This solution is particularly suited for the study of the nuclei, the baso and eosinophil granulations, and it is used by preference for anæmic blood, and also for lymphatic leukæmia.
5. 10 c.c. of a 1 per cent. watery eosin solution, with 8 c.c. methylal, and 10 c.c. of a saturated watery solution of methylene blue are mixed, and used at once, see page 41. Time of staining 1, at most 2 minutes. The staining is characteristic only in preparations very carefully fixed by heat. The mast cell granulations are stained pure blue, the eosinophil red, the neutrophil in mixed colour.
6. Jenner's stain consists of a solution in methyl alcohol of the precipitate formed by adding eosine to methylene blue.
Grubler's water soluble eosine, yellow 1.25% } a.a. watery " medicinal, methylene blue 1% } solutions.
Precipitate allowed to stand 24 hours, and then dried at 55°. It is then made up to 1/2% in methyl alcohol (Merck). The stain may be obtained from R. Kanthack, 18, Berners Street, London, ready for use. It is exceedingly sensitive to acids and alkalis. Fixation is effected by heat. Time of staining 1-4 minutes.
Before we pass to the histology of the blood, two important methods may be described, for which the dried blood preparation is employed directly, without previous fixation: 1. the recognition of glycogen in the blood; 2. the microscopic test of the distribution of the alkali of the blood.