Aurine tricarboxylic acid

VII,10. AMMONIUM SALT OF AURIN TRICARBOXYLIC ACID ( ALUMINON )... 

Alnminon (qualitative test for aluminum). The reagent consists of 0.1% solution of the ammonium salt of aurin tricarboxylic acid. A bright red precipitate, persisting in alkaline solution, indicates aluminum. 

Aurin tricarboxylic acid [4431-00-9] M 422.4, m 300". The acid is dissolved in aqueous NaOH, NaHS03 solution is added until the colour is discharged and then the tricarboxylic acid is ppted with HCI [Org Synth Coll Vol I 54 1947]. Do not extract the acid with hot water because it softens forming a viscous mass. Make a solution by dissolving in aqueous NH3. See Aluminon for the ammonium salt. 

Formaldehyde condenses with salicylic acid in the presence of nitrite-containing sulphuric acid to give aurin tricarboxylic acid this is converted by ammonia solution into the ammonium salt, which is employed as a reagent for aluminium ( aluminon ) ... 

Aluminum in solution of its salts is detected by the reaction (1) with ammonium salt of aurin tricarboxylic acid ( aluminon ), which yields a red precipitate persisting in NH4OH solution, (2) with alizarin red S. which yields a bright red precipitate persisting in acetic acid solution. 

Aluminon (a solution of the ammonium salt of aurine tricarboxylic acid) Quinalizarin, alizarin-S, alizarin Chromium (III), Cr3 Ammonia solution... 

Aurin tricarboxylic acid is of interest as a reagent for detecting aluminium.5... 

The purification of the crude aurin tricarboxylic acid by extracting with hot water1 is undesirable, for the hot water causes the acid to soften, and results in the formation of large viscous semi-liquid masses which cannot be filtered readily. 

Treatment of the acute disease includes bed rest, oxygen therapy, mechanical ventilation when needed, and corticosteroids. Chelation has been used to treat beryllium toxicity however, no one agent is recommended over another. Aurin tricarboxylic acid has been used to protect primates from beryllium overdose, but human trials have not been conducted. 

Oxidative condensation with a phenol. In a procedure for the preparation of aurin tricarboxylic acid, the first step is addition of solid sodium nitrite in small portions with stirring and ice cooling to coned, sulfuric acid to produce a solution of oxidant... 

The method suggested by Caro 2 for the purification of aurin tricarboxylic acid seems to be unnec sary when the dye is to be used as a test for aluminium. In this /nethod the crude product is dissolved in sodium hydroxide, sodium bisulphite is added until the solution is decolorized, and the addition compound of the free acid is precipitated by adding hydrochloric acid. 

The preparation of aurin tricarboxylic acid was first described in a patent3 granted to Geigy, in which the foregoing method is... 

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