STEP 7: Filter and use the stain immediately if necessary. The stain can be filtered and
used immediately. However, it is preferable to allow the stain to age two
weeks before filtering and using it.
STEP 8: Store the stain in an amber bottle. Protect it from light.
(b) Stock buffers. These buffers may be kept in separate glass-
stoppered bottles for a long time.
1 Acid Buffer (M/15) - Solution A.
Sodium phosphate, monobasic.................... 9.5 gm
Distilled water, q.s. to.................................. 1,000.0 ml
2 Alkaline Buffer (M/15) - Solution B.
Sodium phosphate, dibasic, anhydrous ....... 9.5 gm
Distilled water, q.s. to.................................. 1,000.0 ml
Dissolve dibasic sodium phosphate in a small quantity of the
distilled water in a one liter volumetric flask. Add water to make
one liter of solution.
(c) Working buffered water. Check the pH of the solution with an
electric pH meter (pH 7 to 7.2).
Stock acid buffer (M/15) - Solution A................. 39.0 ml
Stock alkaline buffer (M/15) - Solution B ........... 61.0 ml
Distilled Water ................................................... 900.0 ml
(d) Preparation of Triton buffered water solutions. For thin blood films or
combination thin/thick smears, add 1.0 milliliter of stock 10 percent aqueous solution of
Triton X-100 to 1,000 milliliter of buffered water. The resulting concentration of Triton is
0.01 percent. Keep buffered water, a Triton-buffered water, in tightly capped amber
bottles and check the pH of the buffered water before use.
(2)
Procedure. See the following steps and figure 2-4.
STEP 1: Fix the thin film portion of the slide with absolute methanol for 3-5 seconds.
Avoid getting alcohol or alcohol fumes on the thick film. Allow the thin film to
air dry before proceeding.
MD0841
2-17