NWLSS™ 一氧化氮合酶(NOS)活性试剂盒非常适合在洗涤后检测培养细胞的NOS活性。也可以测试细胞裂解物和组织匀浆，但需要测试基线一氧化氮并从定时结果中减去。

Nitric oxide synthase (NOS) is involved in the synthesis of nitric oxide from L-arginine. Mammalian NOS include three distinct isoforms; inducible, endothelial and neuronal. The traditional method for measuring nitric oxide synthase (NOS) activity is performed by radiochemical assay that measures the conversion of L-[3H]arginine to L-[3H]citrulline. This method is expensive and requires regulation of radioactive materials.

In contrast, we offer a non-radioactive method that utilizes a simple NADPH recycling system to allow NOS to operate linearly for hours as nitric oxide derived degradation products nitrate and nitrite accumulate. NOS activity can therefore be assayed spectrophotometrically by measuring total nitrite accumulation over time.

Test Principle

NADPH and L-arginine are required for the continual operation of NOS and production of nitric oxide (NO). In aqueous solution, NO rapidly degrades to nitrate and nitrite. Spectrophotometric quantization of nitrite using Griess Reagent is straightforward, but does not measure nitrate. This kit employs recombinant nitrate reductase (NaR) for conversion of nitrate to nitrite prior to quantization of nitrite using Griess reagent , thus providing for accurate determination of total NOS activity.

Intended Use：Quantifying nitric oxide (NO) in biological samples

Specificity:Nitric Oxide as total Nitrite

Sensitivity:1 pmol/mL or 1µM in the assay

Storage and Stability:1 year from manufacture date when stored at specified temperature

Kit Contents:

Microplates 1 X 96 wells

Reaction Buffer (50 mM HEPES 0.5 mM EDTA 1 X 25 mL

Nitrite Standard (500 µM NaNO2) 1 X 1.5 mL

Nitrate Reductase (Lyophilized) 1 Unit

Nitrate Reductase Buffer 1.2 mL

NADPH Part A (NADP+ , Glucose 6-Phosphate, L-Arginine) 1 mL

NADPH Part B (Glucose 6-Phosphate dehydrogenase) 1 mL

Reagent A: (Sulfanilamide (p-Aminobenzenesulfonamide) in 3N HCl) 1 X 7 mL

Reagent B: (N-(1-Naphthyl) ethylenediamine dihydrochloride in deionized H2O) 1 X 7 mL