WST-1 Cell Proliferation Assay Kit II (ab65475)


  • Product name
    WST-1 Cell Proliferation Assay Kit II
    See all Cell proliferation kits
  • Sample type
    Adherent cells, Suspension cells
  • Assay type
  • Assay time
    4h 00m
  • Product overview

    WST-1 Cell Proliferation Assay Kit II provides by far the easiest and most sensitive means for quantifying cell proliferation and viability. The assay is based on the cleavage of the tetrazolium salt to formazan by cellular mitochondrial dehydrogenase. The amount of the dye generated by activity of dehydrogenase is directly proportional to the number of living cells. The formazan dye produced by viable cells can be quantified by multi-well spectrophotometer (microtiter plate reader) by measuring the absorbance of the dye solution at 440 nm. The assay can be used for measurement of cell proliferation in response to growth factors, cytokines, mitogens, and nutrients, etc. It can also be used for the analysis of cytotoxic compounds like anticancer drugs and many other toxic agents and pharmaceutical compounds. The new method is so simple, just add-and-read, requiring no washing, no harvesting, and no solubilization steps. It is faster, stable, and more sensitive than MTT, XTT, MTS based assays. The assay correlates well with the [3H]-thymidine incorporation assay.
    Visit our FAQs page for tips and troubleshooting.

    This kit was previously called Quick Cell Proliferation Assay Kit II.

    Review our cell health assays guide to learn more about our other cell viability, cytotoxicity and cell proliferation assay kits.

  • Tested applications
    Suitable for: Functional Studiesmore details



Our Abpromise guarantee covers the use of ab65475 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.


  • Mitochondrial dehydrogenases checked in various cell concentrations at different incubation times (2h WST for each condition)

  • HL60 cell proliferation measured after 24h incubation (37°C/5%CO2) and 2h WST at various camptothecin concentrations

  • HL60 cell proliferation measured after 48h incubation (37°C/5%CO2) and 2h WST at various camptothecin concentrations

  • HL60 cell proliferation measured after 72h incubation (37°C/5%CO2) and 2h WST at various camptothecin concentrations



ab65475 has not yet been referenced specifically in any publications.

Customer reviews and Q&As

The primary difference between the quick cell proliferiation assay (ab65473) and quick cell plus proliferation assay (ab65475) is that the ab65475 is more sensitive and more stable.

Thank you for contacting us and your interest in our products.

The Quick Cell Proliferation Assay Kit (ab65473) and Quick Cell Proliferation Assay Kit II (ab65475) should not be affected by serum in your culture medium. Any differences from th...

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As I understand you are looking for an absolute cut-off value for the OD. This is a comparative assay in which you can let the colour develop for an extended period of time to look...

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I have now received an answer from lab. They say the colour might develop with longer incubation of the samples. However, the machine can detect the absorbance only within a certain limit. Keeping that in mind, we reco...

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The phenol red from the sample will be diluted in the reaction buffer to a degree that it will not interfere with the assay.

Thank you for your enquiry. Currently our new lab promotion allows 20% off ALL orders plus FREE shipping on all orders for 3 months. The requirements to be considered a “New Lab” are the following: The lab is created by a scientist starting a completel...

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