6533b832fe1ef96bd129a4b3

RESEARCH PRODUCT

Formation rates and protonation constants of azo dyes in a sodium dodecylsulphate micellar solution.

M.c.garcía Alvarez-coqueG.ramis RamosJ.s.esteve Romero

subject

chemistry.chemical_classificationDiazonium CompoundsSodiumInorganic chemistrychemistry.chemical_elementProtonationmacromolecular substancesDosage formAnalytical ChemistryIonchemistry.chemical_compoundAnilinechemistryMoleculeProtonation constant

description

The effects of a sodium dodecylsulphate micellar solution on the coupling rates of several diazotizated arylamines with N-(1-naphthyl)-ethylenediamine and the shifts in the protonation constants of the corresponding azo dyes are quantitatively studied. Aniline, o-, m- and p-aminobenzoic acids, ethyl p-aminobenzoate and several sulphadrugs are used, and the relationships among the intensity of the effects and the molecular structure of the diazonium ions and the dyes are discussed. A single simplified procedure for the determination of all the substances at pH = 1.3 +/- 0.3, where coupling is quickly completed to directly produce the protonated form of the dyes, is established and applied to the analysis of several pharmaceutical preparations.

10.1016/0039-9140(91)80107-bhttps://pubmed.ncbi.nlm.nih.gov/18965299