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.
