0.5% crystal violet staining solution recipe

Base: 100 mL · Updated 2026-09-30

Used for colony formation assays and viability staining: 0.5% crystal violet in 20% methanol.

🧮 Volume calculator
ComponentAmount Final concentration (1X)
Crystal violet500 mg0.5% (w/v)
Methanol20 mL20% (v/v)
Water (distilled)to final volume

Steps

  1. Dissolve crystal violet in methanol and make up to volume with water.
  2. Filter through paper and store at room temperature.
  3. Remove medium, wash with PBS, stain 10–30 min, rinse with water and dry.

Good to know

⚠ Safety Crystal violet is toxic and stains strongly — wear gloves.

FAQ

What counts as a colony?

Typically a cluster of 50 or more cells.

This is a widely used standard composition. Amounts depend on the hydrate form and purity of your reagents — check the formula weight (FW) on the bottle and follow your institution's safety rules and the manufacturers' instructions.