(R33) 10% Giemsa’s solution   

Composition

-     Giemsa stock solution                                            10 ml

-     Buffered water (pH 7.2)                                         90 ml

Mix well.

This solution is stable for 12 hours at room temperature.

Ready to use Giemsa stock solution is commercially available. Given its instability, it is recommended to purchase only small quantities (100-250 ml) and store at room temperature, sheltered from sunlight and properly sealed.

Do not shake the flask before use: the non-dissolved crystals might return into suspension and deposit on the preparation during staining.

Do not withdraw the stain solution using a plastic or glass pipette, but pour off a small quantity into a clean and dry container. Then use a graduated pipette to withdraw the needed amount of solution. Throw away the remainder; never put it back into the flask.

Buffered water (pH 7.2)

Buffer stock solution

-     KH₂PO₄                                                               2.69 g

-     Na₂HPO₄                                                             8.36 g

-     Distilled water                                                     100 ml

Dissolve the salts in distilled water. Mix well.

Procedure

-     Mix 20 ml buffer stock solution with 1000 ml distilled water

-     Check pH with pH paper or meter.

Mineral waters with different pH values are commercially available.  Buffered water can be replaced with commercially available still mineral water with a declared pH of 7.2.