Phenol red solution, a pH indicator
Phenol red is used as a pH indicator. The sodium salt of phenol red is used widely in culture media to identify shifts from neutral to acidic pH values. It is typically used in cell culture media where ideally a solution of phenol red will have a yellow color at a pH of 6.4 or below and a red color at a pH of 8.2 and above. Notably, phenol red in tissue culture media can act as a weak estrogen, a property associated with the presence of lipophilic impurities, especially observed in human breast cancer cells.
Appearance: Dark red liquid.
pH: 7.0 to 7.6
125 ml, 250 ml