Griess* Reagent

Note Other aromatic amines, e. g. 1- or 2-naphthylamine in acetic acid solution (Griess reagent), can be used as coupling agent instead of N-(l-naphthyl)-ethylenediamine ... 

An improved HPLC-photohydrolysis-colorimetry method was validated for twenty-eight reference nitrosamines. These were separated by HPLC and photolytically cleaved by UV radiation. The resulting nitric oxide was oxidized and hydrolyzed to nitrite ions, which were derivatized into an azo dye with Griess reagent and measured spectrophoto-metrically. The method was applied to separate and detect hitherto unknown nonvolatile nitrosamines in biological fluids and food extracts591. 

Griess reagent analychem A reagent used to test for nitrous add it is a solution of sulfanilic add, a-naphthylamine and acetic add in water. gres re.a jant ... 

Other formulations of the Griess reagent included N,N-dimethyl-l-naphthylamine [33, 44] or N-l-naphthylethylenediamine [45, 46] as the coupling agent. 

In some, more recent formulations, phosphoric acid replaced acetic acid as the acidic medium [46, 48]. The use of hydrochloric acid as a solvent for the Griess reagents had also been reported [45]. 

Laboratory ELITE explosives detection device. Similarly to the aforementioned ETK, it can detect traces of mOitary, as well as homemade explosives, by applying the common Meisenheimer and Griess reagents. Because of the addition of a heating device nd efficient swiping for sample collection, the reported sensitivity of ELITE is 2—50 times higher than that of other commercial field tests [102]. For example, ELITE detection limits for TNT, 2,4-DNT, and tetryl were found to be 50, 100, and 50 ng, respectively. Lower thresholds (25—50ng) were reported for PETN, RDX, HMX, and NC [102]. 

X. Treatment with Modified Griess Reagent. Dissolve in a test tube ca O.lg of the sample... 

NPRO in raw bacon 1. Extraction with water 2. Cleanup on anion-exchange resin None 12 X 0.25 in. /xBondapak C18 (Waters Assoc.) 1% Na2HP04 in water Photohydrolysis followed by detection of nitrite with Griess reagent 85-90 46... 

N02 (by nitrate reductase), which reacted with Griess reagents to produce a colored product to be detected by TLM [1077]. 

Griess reagent solution of sulfanilic acid and a-naphthylamine in acetic acid reagent for nitrites... 

The next pesticide analyzer is described by Singer, et al (6) and used post-column derivatization for a nitrosamide-specific reaction. Following chromatographic separation and UV detection, the stream was air-segmented and treated with the Griess Reagent (Figure 11). The... 

Refs l)Colver(1918), 234-36(Color reaction with NaOH or NH9 solns of nitroderivs of benzene, toluene, naphthalene, etc a table) 2)E. Elvove, IEC II, 860-64(1919) [Modification of Webster s test for colorimetric detn of TNT in urea, described in BritMedJ 2, 845(1916). Instead of using Webster s KOH soln, Elvove proposed to use Griess Reagent(qv)] 3)H.W. 

The undesirable characteristics of this reaction are that HN3 may escape and other toxic vapors may be generated [22]. However, the method destroys the azide ion effectively, as no color reaction can be observed with the Griess reagent for nitrite [23]. The method may be economical for large-scale destruction of azides, but the presence of HN3 may preclude its use. 

Nitrate is frequently measured using the Griess reagent as an index of NO produced. NO itself participates in both reduction and oxidation reactions. Single electron reduction of NO yields the nitroxyl anion, whereas oxidation reactions yield the nitrosonium cation and N2O3+, via autoxidation. Both the NO radical and nitrosonium cation can be involved in direct reactions with biological systems, specifically with amino acid residues such as cysteine, with the resultant production of nitrosothiols (see later). 

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