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How to Make a Stain for a Slide

Creating a stain for a specimen is a basic laboratory procedure used throughout science. Creating a stain adds contrast to different areas of a specimen and aids the researcher in identifying different parts of the organism or items being viewed. The creation of a stain is a two-part process that requires very basic lab items and procedures. Students are often tested on their ability to stain a slide and use a microscope properly.

Cover slips
Stain material
Paper towel
Deionized water (not distilled or mineral water)
Eyedropper

Instructions

- 1
  Place the slide containing the specimen on a lab table.
- 2
  Place one drop of water directly onto the specimen contained on the slide.
- 3
  Hold a cover slip directly over the specimen with one side touching the slide, at a 45-degree angle to the slide.
- 4
  Let the cover slip go, allowing it to fall onto the slide and evenly distribute the water. This is known as a "wet mount."
- 5
  Place one or two drops of stain on the right side of the cover slip.
- 6
  Hold the edge of a paper towel on the opposite side of the cover slip. The paper towel draws the water out of the slide and pulls the stain underneath.
- 7
  Remove the paper towel and clean off any excess stain. The stain should only be underneath the cover slip at this point. The slide is now stained and ready for viewing.

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