Diff-Quik is a commercial Romanowsky stain variant used to rapidly stain and differentiate a variety of pathology specimens. It is most frequently used for blood films and cytopathological smears, including fine needle aspirates. The Diff-Quik procedure is based on a modification of the Wright-Giemsa stain pioneered by Harleco in the 1970s, and has advantages over the routine Wright-Giemsa staining technique in that it reduces the 4-minute process into a much shorter operation and allows for selective increased eosinophilic or basophilic staining depending upon the time the smear is left in the staining solutions.
DiffQuik Staining Procedure
Solutions required
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Fixative (Fast green in methanol) - pale green colour
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Stain solution 1 (Eosin G in phosphate buffer) - red colour
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Stain solution 2 (Thiazine dye in phosphate buffer) - blue colour
Method
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Allow smears to dry
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Dip slide or tape-strip five times, for one second each, into Fixative. Allow excess to drain after each dip.
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Dip slide or tape-strip five times, for one second each, into Stain 1. Allow excess to drain after each dip.
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Dip slide or tape-strip five times, for one second each, into Stain 2. Allow excess to drain after each dip.
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Rinse slide or tape-strip in distilled water or Weise's buffer, pH 7.2.
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Stick tape strip to slide (sticky side down) and remove excess tape.
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Blot or allow to dry in air.
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Examine at low power to identify structures and then under oil immersion.