• Product name
    Nitric Oxide Assay Kit (Fluorometric)
    See all Nitric oxide kits
  • Sample type
    Urine, Serum, Plasma, Other biological fluids, Tissue Extracts, Cell Lysate
  • Assay type
  • Assay time
    3h 00m
  • Product overview

    Abcam's Nitric Oxide Assay Kit (Fluorometric) (ab65327) provides an accurate, convenient measure of total nitrate/nitrite concentration in a simple two-step process. In the first step nitrate is converted to nitrite by nitrate reductase. In the second step, nitrite reacts with the fluorescent probe DAN (2, 3 diaminonaphthalene) and the fluorescence can be measured at Ex/Em = 360/450 nm. NaOH enhances the fluorescent yield. The fluorescent intensity is proportional to the total nitric oxide production. The kit has been tested with culture media, plasma, and tissue homogenates.
    Visit our FAQs page for tips and troubleshooting.

    If you are interested in a colorimetric detection kit, please check Nitric Oxide Assay Kit (Colorimetric) (ab65328).

  • Notes

    Nitric oxide (NO) plays an important role in neurotransmission, vascular regulation, immune response and apoptosis. Since NO is rapidly converted to nitrite (NO2-) and nitrate (NO3-), the total concentration of nitrite and nitrate is used as a quantitative measure of NO production.

  • Tested applications
    Suitable for: Functional Studiesmore details


  • Storage instructions
    Store at -20°C. Please refer to protocols.
  • Components Identifier 200 tests
    Assay Buffer WM 1 x 30ml
    DAN Probe Amber Red 1 x 1ml
    Enhancer (Lyophilized) Purple 1 vial
    Enzyme Cofactor (Lyophilized) Blue 1 vial
    Microtiter plate 2 units
    Nitrate Reductase (Lyophilized) Green 1 vial
    Nitrate Standard (Lyophilized) Yellow 1 vial
    Nitrite Standard (Lyophilized) Orange 1 vial
    Plate Cover 2 units
    Sodium Hydroxide Clear 1 x 1ml
  • Research areas
  • Relevance
    Nitric oxide (NO) is a key vertebrate biological messenger, playing an important role in neurotransmission, vascular regulation, immune responses and apoptosis. NO , also known as "endothelium-derived relaxing factor" or "EDRF", is synthesized from L-arginine, oxygen and NADPH by various NO synthases. Most of the NO in the cell is oxidized to nitrite (NO2-) and nitrate (NO3-), and therefore the concentrations of these anions are generally as a quantitative measure of NO production.


Our Abpromise guarantee covers the use of ab65327 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.


  • Nitric oxide measured in cell lysates showing quantity (micromol) per 106 cells tested

  • Nitric oxide measured in biologicals (average of 1:6 and 1:12 dilutions) showing concentration (micromolar)

  • Nitrite, nitrate assay in the presence and absence of nitrate reductase. Assays were performed according to the kit protocol with 1 hour conversion of nitrate to nitrite at Step 5.



This product has been referenced in:
  • Komalavilas P  et al. Vascular surgical stretch injury leads to activation of P2X7 receptors and impaired endothelial function. PLoS One 12:e0188069 (2017). Read more (PubMed: 29136654) »
  • Huang Z  et al. Stimulation of Unprimed Macrophages with Immune Complexes Triggers a Low Output of Nitric Oxide by Calcium-dependent Neuronal Nitric-oxide Synthase. J Biol Chem 287:4492-502 (2012). Read more (PubMed: 22205701) »

See all 2 Publications for this product

Customer reviews and Q&As

Thank you for contacting us.

I heard back from the lab and they will check the assay buffer, but they would need to know the lot number you have. If you please could send me your order or PO number (or lot number on the kit), I will let them...

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Me confirman mis compañeros que la enzima Nitrato Reductase contenida en el kit proviene de Aspergillus, y en caso de interesaros podríais comprarla de forma independiente del kit.

The lab has confirmd that your lysis buffer would be compatible, and that pretty much any generic lysis buffer with a mild detergent will work.

Thank you for contacting us.

For tissue samples: Start with 10-50 mg of the tissue, add 500-1000 μl (or ˜3-4 volumes of tissue size) of the assay buffer on ice, homogenize using a Dounce homogenizer (10-50 passes) on ice, until efficient ...

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Thank you for your enquiry regarding ab65327.

We have nottested this kit in frozen tissue in our lab. However, if the samples were frozen appropriately, there is still a possibility that this kit might work on lysates from such tissues.

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Thank you for your reply.
I am sorry that you are not happy with this kit. Please see below for the refund information.

The deproteinization step would apply for the samples, not for the standard curve.

The lab also send me th...

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Thank you for your email.

As I had mentioned in a previous email, I would be happy to replace the kit for you. Can you please confirm thatthis is what you prefer or rather a credit or refund?

On the same hand, it is important to us ...

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At the moment, we do not know if there is something wrong with the kit (as the lab tested the assay buffer and it was fine) or with the way the samples were prepared or measured.

Can you please let me know what exactly was added to the wells ...

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Thank you for your email.
I will pass the data and information to the lab for evaluation.

In the meantime, they have checked the assay buffer andit did not produce any RFU in their QC testing done this morning. Thus, the buffer seems to ...

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Thank you for the information. I found your order in the system.

Could you please clarify what Group A, B, and C stand for or maybe how they differ? Are these the same samples in triplicate?
Column 1 thru 6 contain data, but what i...

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