Keliher, "Spectrophotometric determination of nitrite with composite reagents containing sulphanilamide, sulphanilic acid
or 4-nitroaniline as the diazotisable aromatic amine and N-(1-Naphthyl)ethylenediamine as the coupling agent," Analyst, vol.
This study reports a simple FI spectrophotometric method for the determination of ANTU in natural waters, based on the conversion of nitrite into nitrous acid, subsequent diazotization of sulphanilic acid
, and formation of the diazonium salt.
A number of methods have been reported for the synthesis of 3,4-dihydropyrano[c]chromenes with the catalysts such as pyridine , [K.sub.2]C[O.sub.3], diammonium hydrogenphosphate , MgO , TBAB , Si[O.sub.2]PrS[O.sub.3]H , 4-(dimethylamino)pyridine (DMAP) , trisodium citrate , ammonium acetate , polymer supported sulphanilic acid
, basic ionic liquid , CuO nanoparticles , p-dodecylbenzenesulfonic acid , amberlyst A21, silica-grafted ionic liquid  Ti[O.sub.2] , thiourea dioxide , [Fe.sub.3][O.sub.4]@SiO2-imid-PMAn nanoparticles , and A,A-dimethylbenzylamine (DMBA)  have also been reported to promote this reaction.
As shown in Scheme 3, the expected products of the reaction between AO7 and metallic iron in acidic conditions are sulphanilic acid
(SA) and 1A2N, arising from the reductive cleavage of the azo bond.
Separation was performed with acetonitrile/ methanol/water (1:1:1) as a solvent system and visualized by short wave length (245 nm) and diazotized sulphanilic acid
. Rf value for the spot confirming 2,4-DAPG was calculated (13).
Then Griess reagent (20 L, 0.3% sulphanilic acid
in glacial acetic acid + 0.1% naphthylethylenediamine (NED): equal volumes of both solutions mixed just before use) was added to each well plate and the mixture kept at room temperature for 20 min to develop the color.
, DTO, and formaldehyde (37%) for synthesis of DTOF and SDTOF resins.
The Griess reagent is based on the two-step diazotization reaction in which acidified nitrite produces a nitrosating agent, which reacts with sulphanilic acid
to produce the diazonium ion.
Most clinically used methods for the determination of bilirubin and its conjugates (in the form of esters of mono- and diglucuronide of bilirubin and albumin covalently bound) are based on its reaction to diazotised sulphanilic acid
. Ehrlich described it as early as in 1883.
The RLG group currently has a diversified product portfolio that includes acetanilide, acetic anhydride, acetic acid, industrial alcohol, aniline oil and sulphanilic acid
. The group's day-to-day operations are managed by Mr.
N-(1-naphthyl) ethylene Diamine Dihydrochloride (NEDD), Sodium nitoprusside, sulphanilic acid
, sodium chloride (NaCl), Ferric Chloride (FeCl3), disodium hydrogen orthophosphate, potassium dihydrogen phosphate, 2,2'-Azino- bis(3ethylbenzothiazoline-6-sulfonic acid) (ABTS), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), 1,10-Phenanthroline and Folin-Ciocalteu Reagent.