Crystal Violet Assay
This is a simple assay useful for obtaining quantitative information about the relative density of cells adhering to multi-well cluster dishes. The dye in this assay, crystal violet, stains DNA. Upon solubilization, the amount of dye taken up by the monolayer can be quantitated in a spectrophotometer or plate reader.
Carefully remove culture medium from wells.
Wash plate gently with PBS warmed at least to room temperature:
| Number of wells | Volume |
| 96 | 0.2 mL |
| 48 | 0.5 mL |
| 24 | 1 mL |
| 12 | 2 mL |
| 6 | 3 mL |
Carefully remove PBS and add crystal violet solution . Incubate 10 minutes at room temperature:
| Number of wells | Volume |
| 96 | 50 uL |
| 48 | 100 uL |
| 24 | 200 uL |
| 12 | 500 uL |
| 6 | 750 uL |
Wash plate 2x in tap water by immersion in a large beaker. Be careful not to lift off cells. Change tap water between washes.
Drain upside down on paper towels, than add 1% SDS to solubilize the stain:
| Number of wells | Volume |
| 96 | 100 uL |
| 48 | 300 uL |
| 24 | 600 uL |
| 12 | 1 mL |
| 6 | 1.5 mL |
Agitate plate on orbital shaker until color is uniform with no areas of dense coloration in bottom of wells.
Read absorbence of each well at 570 nm.
