Wroblewska, Elwira Katarzyna published the artcile5-(3-Bromo-4-hydroxy-5-methoxyphenyl)-7,7-dimethyl-7H-indolo[1,2-a]quinolinium perchlorate as a new indicator for anionic surface active agents determination. Part II. Influence of pH on the titration results, Application of Dimidium bromide, the publication is Tenside, Surfactants, Detergents (2011), 48(2), 127-129, database is CAplus.
The work refers to the already published modification of widely used method for anionic active agents determination which concerns the replacement of the mixed indicator, consisting of Acid Blue 1 and carcinogenic Dimidium Bromide, applied in the International Standard ISO 2271:1989 with solvatochromic dye, i.e. 5-(3-bromo-4-hydroxy-5-methoxyphenyl)-7,7-dimethyl-7H-indolo[1,2-a]quinolinium perchlorate (1). The value of pKa for examined dye (1) amounts to 6.59, and the effect of pH of the probes on the anal. results was studied, i.e. precision of determination of titration endpoint. The change of pH for aqueous and apparent pH for organic phase were determined during the titration process. It was shown that there was no effect of the pH change in the range from 3.5 to 5.0 on the results. The modification of the method for the probes which pH do not fit to the above range is presented.
Tenside, Surfactants, Detergents published new progress about 518-67-2. 518-67-2 belongs to bromides-buliding-blocks, auxiliary class Other Aromatic Heterocyclic,Salt,Amine,Benzene, name is Dimidium bromide, and the molecular formula is C9H21NO3, Application of Dimidium bromide.
Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary