Photomicrographs

Section:MICROORGANISMS Subsection:METHODS
3 Phenol cotton blue or lactofuchsin stain
Date Composed: 12-19-95 Date Modified:01-18-96

III. Phenol cotton blue or lactofuchsin stain

A. Materials

1. Sample to be observed

2. Microscope slides

3. Cover glasses

4. Phenol cotton blue stain or lactofuchsin stain

B. Procedures

1. Flame one side of the slide in the flame of your Bunsen burner to remove any oil
or grease. Allow the slide to cool.

2. Add a drop of phenol cotton blue or lactofuchsin to the center of the slide.

3. Transfer a small amount of the sample to be examined from the culture to the drop
of phenol cotton blue on the slide. Tease the sample with two dissecting needles
to separate it so that they can be easily seen.

4. Pass the slide through a flame several times until the stain begins to bubble. Cool
the preparation.

5. Place a clean cover glass over the preparation and examine it under the lower power
and high dry lenses of your microscope. The organisms will have been stained by
the phenol cotton blue and will appear different shades of blue.

NOTE: Phenol cotton blue and lactofuchsin stain fumes are toxic. Avoid inhalation.