Neutral Red

CAS: 553-24-2

Ref. 3D-N-2527

Product Information

• Name: Neutral Red
• Synonyms: 3-Amino-7-dimethylamino-2-methylphenazine hydrochloride
• Brand: Biosynth
• Description: Transition of pH Indicator: pH 6.8 - 8.0, red to yellow. Neutral red is a dye used in histology for staining nuclei. Neutral red is also a pH indicator. As such it is used in microbial culture media for differentation of bacteria. For example MacConkey agar contains Neutral red and lactose. Acidification by lactic acid turns on the Neutral red. Therefore, colonies formed by bacteria that ferment lactose into lactic acid will turn red and stand out from the pale colonies of non-lactose-fermenting bacteria. Neutral red is also used in cell viability tests based on the ability to incorporate and bind Neutral red.

Chemical properties

• Molecular weight: 288.78 g/mol
• Formula: C₁₅H₁₇ClN₄