Giemsa staining of cells:

Mix equal volume of culture of L. tarentolae with 0.25 M sucrose –1% bovine serum albumin. Can use 200 ul of a stationary phase culture (~100-200 X 10⁶/ml).

Centrifuge in Microfuge 30 sec.

Aspirate off supernate. Resuspend pellet in ~equal vol. sucrose-BSA. Spread 1 µl on clean glass slide. Air-dry rapidly using compressed air. The concentration of cells is critical for good staining. Try several additional dilutions also.

Fix cells in cold methanol in Coplin jar for 5 min. Air dry. Stain in fresh Giemsa for 30 min. Mix 1-2 ml stock Giemsa with 40 ml 0.02 M Tris-HCl (pH 7.4). Rinse and dry.

Examine first using high dry 40 X phase bright field, and then with oil immersion at100 X.