Fast Blue Salt BB

Note The detection is not affected if the dipping solution exhibits a slight opalescent turbidity. Fast blue salt BB [18] or fast blue salt RR [18,19] can be employed in the reagent in place of fast blue salt B. It is occasionally preferable not to apply spray solutions I and II separately but to work directly with a 0.1% solution of fast blue salt B in caustic soda solution (c=l—2mol/l) [13, 15] or in 0.5% methanolic caustic potash [3]. 

Note The alternative fast blue salt BB produced the most intensely colored chromatogram zones for visual analysis in daylight, while fluorescence quenching in UV light (A = 254 nm) was greater with fast blue salt B and fast blue salt RR (Figs. 1 and 2). 

Fast blue salt B, fast blue salt BB, fast black salt K, diazotized sulfanilic acid (Pauly s reagent), diazotized sulfanilamide or 4-nitroaniline... 

Phenols (capable of coupling) Fast blue salt B, fast blue salt BB, fast black salt K, diazotized sulfanilic acid (Pauly s reagent) diazotized sulfanilamide or 4-nitroaniline Intensely colored azo dyes are formed. Catecholamines [20, 3S], imidazoles [21] and amines capable of coupling also react. [3, 17]... 

Dipping solution Dissolve O.S g fast blue salt BB (C.I. 3717S) in 2S ml water and make up to 100 ml with methanol [1]. 

Spray solution Dissolve 0.5 g fast blue salt BB in 100 ml water [2]. 

Fast blue salt BB couples with phenols, preferably in alkaline medium, to yield intensely colored azo dyes. 

The reagent solutions should always be prepared fresh and fast blue salt BB should be stored in the refrigerator. 

The diazotization of amines is somewhat troublesome and stock solutions cannot be stored for long because of their lack of stability. There was, therefore, a great demand for stabilized diazonium salts which, when dissolved in water, would immediately be ready for use. Such products are usually marketed under the name of Fast Salts such as Fast Red Salt RL, Fast Blue Salt BB, the Brentamine Fast Salts, etc. The earliest of these were the so-called anti-diazotates. 

Note The detection is not afTected if the dipping solution exhibits a slight opal-escent turbidity. Fast blue salt BB [1R] or fast hlim salt R R [1R 1Q] ran tv pmplnypH... 

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