Nitric Oxide (NO) Detection

DAA reacts with nitric oxide (NO) to form a red (_em > 580 nm) fluorescent precipitate. DAA probe has been used to detect NO concentration in rat retinas after injury to the optic nerve.

• Yellow orange solid soluble in DMSO
• Store at -20°C
• C₁₄H₁₂N₂O₆S
• Mwt: 336.32

2,3-Diaminonaphthalene reacts with nitrosonium, which is formed from NO, to form the fluorescent dye 1 H-naphthotriazole.^1,2 Using this method, 10nM to 10µM of nitrite (NO₂-) can be detected and the detection is compatible with 96-well format.³

• Yellow orange solid soluble in DMSO
• Store at -20°C
• C₁₀H₁₀N₂
• Mwt: 158.

Griess reagent is used to detect nitrite photometrically. The reagent contains two chemicals, sulfanilic acid and N-(1-naphthalenediamine). Under acidic condition sulfanilic acid is coverted by nitrite to a diazonium salt, which readily couples with N-(1-naphthalenediamine) to form a highly colored azo dye that can be detected at 548 nm (Figure 5.1). Under physiological condition, NO is unstable and is rapidly oxidized to a mixture of nitrite and nitrate. In order to measure NO level indirectly from nitrite, nitrate is reduced to nitrite enzymatically via nitrate reductase so that the total amount of nitrite can be measured. The kit provides a pre-mixed, read-to-use Griess reagent and also a vial of nitrite solution as a standard for generating a calibration curve. A detailed protocol is provided for each purchased product.