Bromophenol blue is used as a tracking dye in electrophoresis, as a color marker in gel electrophoresis and polyacrylamide gel electrophoresis. As a biological stain, it plays an important role to stain proteins and nucleic acids. It acts an intermediate and an acid-base indicator in the pH range 3.0 to 4.6.

This Thermo Scientific Chemicals brand product was originally part of the Alfa Aesar product portfolio. Some documentation and label information may refer to the legacy brand. The original Alfa Aesar product / item code or SKU reference has not changed as a part of the brand transition to Thermo Scientific Chemicals.