Assay nitric oxide (NO) composition and total as separate values of nitrate (NO3-) and nitrite (NO2-) levels in urine, saliva, plasma, serum and other biological fluids with our Thermo Scientific Nitric Oxide Assay Kit.
This nitric oxide assay kit is for quantitative determination of nitrite (NO2-) and nitrate (NO3-) in biological fluids. The kit uses the enzyme nitrate reductase to convert nitrate to nitrite. Nitrite is then detected as a colored azo dye product of the Griess reaction that absorbs visible light at 540nm. The interaction of nitric oxide (NO) in a system is measured by the determination of both nitrate and nitrite concentrations in the sample. The relative levels of nitrite and nitrate can vary substantially, therefore the most accurate determination of total NO production requires measurement of both nitrate and nitrite.
- Target: nitric oxide (NO) and relative levels of nitrite (NO2-) and nitrate (NO3-)
- Format: colorimetric stain (azo dye) for clear 96-well plates
- Measurement: absorbance at 540nm (±20nm)
- Assay Range: 0 to 100μM
- Sensitivity: 0.222μM nitrite; 0.625μM nitrate
- Precision: dependent upon several factors (generally, intra- and inter-assay CV ≤ 5%)
- Sample Types: urine, saliva, plasma, serum and other biological fluids
- Total Assay Time: 15 minutes (nitrite assay); 45 minutes (nitrate assay)
- Sample Size: 50μL
Complete kit contains Griess reagents, nitrite and nitrate standards, nitrate reductase, NADH, and diluents.
Two microplates are necessary to perform this assay. One plate is used to measure the amount of nitrite in each sample. For the second plate, all of the nitrate in each sample is converted to nitrite using nitrate reductase enzyme and the “total” amount of nitrite (pre-existing nitrite plus nitrate that was converted) is measured. The nitrite measurements from plate 1 are subtracted from the total nitrite measurements in plate 2 in order to calculate nitrate concentrations. This kit is specifically designed for researchers concerned with the relative levels of nitrate and nitrite in each sample.