Call 408.493.1800 | Fax 408.493.1801 | Toll Free 800.891.9699 (US Only) | Email: [email protected]

Nitric Oxide Synthase (NOS) Activity Assay Kit (Fluorometric)

Ultrasensitive, Simple, HTP adaptable fluorometric assay kit for NOS activity measurement
Catalog #: K206

Product Details

Cat # +Size K206-100
Size 100 assays
Detection Method Fluorometric analysis (Ex/Em = 360/450 nm)
Species Reactivity Mammalian samples
Applications Detection of NOS activity
Features & Benefits • Simple, HTP adaptable protocol
Sensitivity as low as 0.75 µU of NOS activity
Fluorometric detection
Kit Components • NOS Assay Buffer
• NOS Dilution Buffer
• NOS Substrate
• NOS Cofactor 1
• NOS Cofactor 2 (25X)
• Nitrate Reductase
• NOS (Positive Control)
• Enhancer
• Nitrite Standard
• Probe
• NaOH
Storage Conditions -80°C
Shipping Conditions Dry Ice
USAGE For Research Use Only! Not For Use in Humans.


Nitric oxide synthases (EC (NOS) are a family of enzymes that catalyze the production of nitric oxide (NO) from L-arginine. Nitric oxide (NO) plays an important role in neurotransmission, vascular regulation, immune response and apoptosis. In presence of NADPH, FAD, FMN, (6R)-5,6,7,8-tetrahydrobiopterin, calmodulin and heme, NOS catalyzes a five-electron oxidation of the guanidino nitrogen of L-arginine with molecular oxygen to generate NO and L-citrulline. There are three isoforms of NOS: endothelial (eNOS), neuronal (nNOS), and inducible (iNOS). nNOS accounts for the production of NO in central nervous system, where NO participates in cell communication and information storage. eNOS produces NO in blood vessels and is involved in regulation of vascular function. In contrast to other isoforms, iNOS is expressed de novo under oxidative stress conditions and produces large amounts of NO as a part of body’s defense mechanism. BioVision’s Nitric Oxide Synthase Activity Assay Kit provides an accurate and convenient method to assay NOS activity in a variety of samples. In this assay, nitric oxide generated by NOS undergoes a series of reactions and reacts with the fluorescent probe to generate a stable signal at Ex/Em = 360/450 nm, which is directly proportional to NOS activity. The assay is simple, sensitive and high-throughput adaptable and can detect as low as 0.75 µU of NOS activity.

Why buy BioVision Products?
Global Presence
Technical Support
BioVision aims to provide our customers innovative tools for accelerating drug discovery and biological research. BioVision offers >8,000 products including the most comprehensive array of assay kits for key targets in Metabolic pathways.
BioVision is committed to providing the highest quality products at a competitive price.
We have a broad network of global distributors who are ready to address your research needs and ensure fast delivery.
Our highly trained Technical Support team provides comprehensive product support and is dedicated to resolving your issues quickly and efficiently.
Can the kit be used on muscle tissue homogenates specifically?
The kit can be used with most tissue extracts, provided that the tissues are well homogenized and contains >5µU of NOS activity.
There are 3 isoforms of NOS. Which isoform is included in the positive control?
The positive control is an inducible mouse NOS expressed and purified from E.Coli.
Can this kit work with live cells?
Unfortunately, this is an endpoint assay where the cells need to be lysed. However, our kit K207-100 let's you determine intracellular NOS activity.
Can we use frozen samples with this assay?
Although we recommend using fresh samples, but the assay can work with frozen samples as well.
Can detect the NO level of tissues or just the NOS enzymes?
The kit allows you to calculate the NOS enzyme activity in your tissues. Please refer to Fig c in the datasheet.
Can the kit work on bacteria or yeast cells?
The kit has been standardized for mammalian cells only
What is the exact volume of sample required for this assay?
There is no specific volume we can recommend for the amount any sample to be used since it is completely sample concentration and quality based. You have to do a pilot expt with multiple sample volumes to determine the optimal volume which gives a reading within the linear range of the standard curve. Please refer to the citations for this product to see what other clients have used with similar sample types.
Do you have trial sizes of this kit?
Unfortunately, we do not have trial sizes of this kit available. However, if you are based in the US or Canada, we will give you a 10% off list price introductory discount on its purchase price. If you are based out of this area please contact your regional BioVision distributor.
Can we purchase individual components of this kit?
Yes, you can purchase any of the kit's components without the whole kit. Please refer to the component Cat #s mentioned on the datasheet for ordering.
Can we use an alternate buffer for sample preparation (cell lysis, sample dilutions etc)?
Our assay buffers are optimized for the reactions they are designed for. They not only contain some detergents for efficient lysis of your cells/tissue, but also contain some proprietary components required for the further reactions. Therefore, we highly recommend using the buffers provided in the kit for the best results.