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10-Acetyl-3,7-dihydroxyphenoxazine (Amplex® Red)

10-Acetyl-3,7-dihydroxyphenoxazine (Amplex® Red), is regarded as the best fluorogenic substrate for peroxidase and H2Obecause it is highly sensitive, specific and stable.

Product Attributes

CAS number



571/585 nm (end product)

Note: Due to operating restrictions related to our COVID-19 response, primary antibody conjugates of R-PE, APC, PerCP, HRP, or AP are temporarily unavailable. All other antibody options are still available. We apologize for the inconvenience. Please see our easy-to-use Mix-n-Stain™ Antibody Labeling Kits for labeling antibodies with R-PE, APC, tandem dyes, and enzymes.
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5 mg
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Product Description

10-Acetyl-3,7-dihydroxyphenoxazine (N-Acetyl-3,7-dihydroxyphenoxazine or ADHP), which has been marketed under the name Amplex® Red, is regarded as the best fluorogenic substrate for peroxidase because it is highly specific and stable. The substrate itself is nearly colorless and nonfluorescent until it is oxidized by H2O2 (reacting in a 1:1 stoichiometry) in the presence of horseradish peroxidase (HRP) to become the highly red fluorescent resorufin. H2O2 is produced by many enzymatic reactions, and therefore ADHP can be used to detect the activity of many different enzymes.

  • Detect HRP in immunoassays
  • Detect trace amounts of hydrogen peroxide (H2O2)
  • Detect using fluorometer or microplate reader
  • λExEm (pH 9)= 571/585 nm (end product)
  • ε= 54,000 (end product)
  • White to off-white solid soluble in DMSO or DMF
  • Store desiccated at -20°C and protect from light
  • C14H11CNO4
  • MW: 257.24
  • [119171-73-2]

High purity resorufin (10062) is also available from Biotium to be used as a standard.


Amplex Red is a registered trademark of Thermo Fisher Scientific.


1. Biosensors and Bioelectronics (2010) doi:10.1016/j.bios.2010.07.126

2. Cancer Biotherapy and Radiopharmaceuticals 25(4), 439 (2010).

3. Anal Biochem 287, 196 (2000).

4. J Immunol Methods 202, 133 (1997).

5. Anal Biochem 253, 169 (1997).


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