Myeloperoxidase (MPO) Activity Assay Kit (Fluorometric) (ab111749)


  • Product nameMyeloperoxidase (MPO) Activity Assay Kit (Fluorometric)
    See all Myeloperoxidase kits
  • Sample type
    Cell culture supernatant, Tissue Extracts
  • Assay typeEnzyme activity
  • Sensitivity
    > 0.001 mU/well
  • Species reactivity
    Reacts with: Mammal
  • Product overview

    Myeloperoxidase (MPO) Activity Assay Kit (Fluorometric) (ab111749) provides a rapid, simple and reliable method to study MPO activity. MPO catalyzes the production of sodium hypochlorite (NaClO) from hydrogen peroxide (H2O2) and sodium chloride (NaCl). Subsequently, NaClO will react stoichiometrically with the free radical sensor Aminophenyl fluorescein (APF) to generate fluorescein, whose fluorescence can be detected at Ex/Em = 485/525 nm. This kit can be used to detect MPO activity as low as 0.5 µU per well. This kit is suitable for high throughput assay of MPO activity.
    Visit our FAQs page for tips and troubleshooting.

  • Notes

    Myeloperoxidase (MPO) is a peroxidase enzyme (EC most abundantly present in neutrophil granulocytes. It is a green hemoprotein found in neutrophils and monocytes that catalyzes the reaction of hydrogen peroxide and halide ions to form cytotoxic acids and other intermediates that play a role in the oxygen-dependent killing of tumor cells and microorganisms. Its heme pigment causes the green color in secretions rich in neutrophils, such as pus and some forms of mucus. Furthermore, it can oxidize tyrosine to a tyrosyl radical using hydrogen peroxide as an oxidizing agent.

  • Tested applicationsSuitable for: Functional Studiesmore details


  • FunctionPart of the host defense system of polymorphonuclear leukocytes. It is responsible for microbicidal activity against a wide range of organisms. In the stimulated PMN, MPO catalyzes the production of hypohalous acids, primarily hypochlorous acid in physiologic situations, and other toxic intermediates that greatly enhance PMN microbicidal activity.
  • Involvement in diseaseDefects in MPO are the cause of myeloperoxidase deficiency (MPD) [MIM:254600]. MPD is an autosomal recessive defect that results in disseminated candidiasis.
  • Sequence similaritiesBelongs to the peroxidase family. XPO subfamily.
  • Cellular localizationLysosome.
  • Information by UniProt
  • Alternative names
    • 84 kDa myeloperoxidase
    • 89 kDa myeloperoxidase
    • EC
    • EC1.11.2.2
    • fj80f04
    • MPO
    • mpx
    • myeloid-specific peroxidase
    • Myeloperoxidase
    • Myeloperoxidase heavy chain
    • Myeloperoxidase light chain
    • wu:fj80f04
    see all


Our Abpromise guarantee covers the use of ab111749 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
Functional Studies Use at an assay dependent dilution.

Myeloperoxidase (MPO) Activity Assay Kit (Fluorometric) images

  • a. Measurement of MPO activity in WBC lysate (0.1 μg) and MPO Positive Control (3 μL). b. MPO specific activity in WBC lysate.

  • Standard Curve using this kit protocol (Ex/Em = 485/525 nm)


References for Myeloperoxidase (MPO) Activity Assay Kit (Fluorometric) (ab111749)

ab111749 has not yet been referenced specifically in any publications.

Product Wall

MPO activity of ovine lung tissue

Good Good 4/5 (Ease of Use)
Application: ELISA - MPO fluorometric assay
Samples: 10mg of homogenized lung tissue in 400uL of assay buffer
Loading amount: NEAT
Followed assay protocol to determine neutrophil infiltration in sheep lung tissue.
Standard curve: very high readings, out of range of neat samples - considered diluting standard to get within reference range
Positive control: was at the bottom end of the standard curve and used as a reference only to check the assay was working correctly

Ms. Gabriela Simonova

Verified customer

Submitted Sep 03 2014

The laboratory confirmed that the assay buffer will be compatible with a BCA assay, and this method of normalizing your samples' protein concentration would be appropriate in order to make activity level comparisons between your samples.

For peroxidase, fresh samples are the best. If needed the tissue can be quick-frozen in liquid nitrogen and stored at -80C. I would not advise making the lysate and then storing it for best results.

Thank you for your enquiry regarding ab111749.

We have always used with fresh samples only with this assay. We know of scientists who did store the homogenates in aliquots at -80°C for a short while before use but since we don’t our...

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The homogenized samples can be stored in aliquots at -80°C, w/o addition of any other components to the assay buffer. It would be preferable though to use fresh samples.
“V” is the volume of the sample you add to the wells in step ...

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This kit can be used with all mammalian samples including rats.

I have updated our datasheet accordingly.

This is an enzymatic activity assay. Enzymes need some ions/cofactors to function and EDTA being a chelator will chelate these co-factors (specifically Mg++ and Ca++), leading to the enzyme becoming non-functional.

Thank you for your inquiry and your patience with this reply.

I heard back from the supplying laboratory that the concentration of the positive control MPO does not vary from lot to lot. But unfortunately, they could not disclose the concent...

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For this assay kit, the client can either use a black opaque bottom plate or, for even more efficiency, use a white opaque bottom plate. One would not use a clear transparent plate.

I am awaiting a reply from the lab which supplies this kit. However I believe you can use a plate with either clear well bottoms or opaque well bottoms to detect fluorometric signal. Although you would use a clear bottom well if you need to v...

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