Myeloperoxidase (MPO) Activity Assay Kit (Colorimetric) (ab105136)


  • Product nameMyeloperoxidase (MPO) Activity Assay Kit (Colorimetric)
    See all Myeloperoxidase kits
  • Sample type
    Cell culture supernatant, Urine, Serum, Plasma, Other biological fluids
  • Product overview

    Myeloperoxidase (MPO) is a peroxidase enzyme (EC most abundantly expressed in neutrophil granulocytes. It is a lysosomal protein stored in the azurophilic granules of the neutrophil. Myeloperoxidase contains a heme pigment which causes its green color in secretions rich in neutrophils, such as pus and some forms of mucus. Myeloperoxidase catalyzes the production of hypochlorous acid (HClO) from hydrogen peroxide (H2O2) and chloride anion (Cl-, or the equivalent from a non-chlorine halide). Myeloperoxidase also oxidizes tyrosine to a tyrosyl radical using hydrogen peroxide as an oxidizing agent. In ab105136, the HClO produced from H2O2 and Cl- is reacted with taurine to generate the taurine chloramine, which subsequently reacts with the TNB2- probe to eliminate color (lambda = 412 nm). The kit provides a rapid, simple, sensitive, and reliable test suitable for high throughput activity assay of Myeloperoxidase. This kit can be used to detect Myeloperoxidase as low as 0.05 mU per well.

  • Notes

    Store the kit at -20 °C protected from light. Allow the Assay Buffer to warm to room temperature before use. Briefly centrifuge vials before opening. Read the entire protocol prior to performing the assay.

  • Tested applicationsFunctional 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
    • MPO
    • Myeloperoxidase heavy chain


Our Abpromise guarantee covers the use of ab105136 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 (Colorimetric) images

  • a. Measurement of MPO activity using WBC lysate (3 μg) and MPO Positive Control (5 and 10 μL). b. MPO specific activity in WBC lysate.

  • Typical standard curve for ab105136.


References for Myeloperoxidase (MPO) Activity Assay Kit (Colorimetric) (ab105136)

ab105136 has not yet been referenced specifically in any publications.

Product Wall

Higer reading in sample

Inconclusive Average 3/5 (Ease of Use)
I homogenized mouse lever tissues using Bio Masher(nippi) .
First time I used Pestle motor for nippi Bio masher (Left image).
Second Bio Masher using no Pestle motor (Right image).
I can't measure samples OD by automated homoginizer.
First time OD can't be measured diluted with MPO Assay Buffer 1:1000.
Second time OD can be measured at dilution 1:30 (homoginized by hand manual).

Machiko Hiraga

Verified customer

Submitted Aug 21 2014

When we measure the positive controls we do it kinetically over time. Then we select a time between 30 mins to 2 hours and make the graph. It is important to note that the activity of the positive control varies from lot to lot and the essence of this ...

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Although it would be preferable to use fresh samples it is probably ok to use frozen serum/plasma with this kit. We ourselves have always used fresh samples with this assay however, we know of scientists who used tissue homogenates stored at -80°C ...

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The composition of the MPO assay buffer is proprietary. However we can share that it is a Citrate-based buffer containing 50 mM Taurine and 0.1% NP-40.

Thank you very much for you call today and for letting us know about the problem with this tube of probe.

As we discussed, please send me the original order or PO number, and I'll see if we can just send you a replacement vial of the probe. <...

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