Pauly reagent

The Pauly reagent will react with histidine, tyrosine, thyroxine, and dihydroxyphenylalanine to give a bright yellow and red color. Diiodotyrosine and creatinine give much weaker reactions. 

In order to prepare the Pauly reagent two solutions, solution I (0.4 M sodium sulfanilate in water) and solution II (0.4 M sodium nitrite in water) are made separately. Just before use, solution I with solution II, 0.25 M HC1, and 2 M NaOH (1 1 8 10) are mixed successively. This solution, which is not stable, should be applied as a spray within minutes and discarded. The ninhydrin test will not interfere with the Pauly reagent. 

In contrast to the dimer, the subunit is denatured by periodate, Pauly reagent, and ionic detergents, and is readily digested by proteolytic enzymes. 

Papain 40,42 paper chromatography procedures 181, 182 Pauly reagent... 

Preparation of the Pauly reagent 0.5 g of diazobenzenesulphonic acid are dissolved in 50 ml of 10% sodium carbonate solution. After complete dissolution (careful stirring or shaking) 50 ml of distilled water cooled to 4 °C or 50 g of crushed ice are added. The solution is filled into a brown bottle and kept cooled in an ice bath during use. 

Purified TRH is partially sol in chloroform, highly sol in absolute methanol. Completely insol in pyridine. Inactivated by diazoiized sulfanilic acid (Pauly reagent) and by plasma, serum, or whole blood in vitro. Resists inactivation by proteolytic enzymes. 

Histidine 238 Diazotised sulphanilic acid or ( sulfanJlamide ( Pauly reagent ) ... 

Bromophenol blue-methyl red-Pauly reagent for phenols. 

SulphanUic acid, diazotised (Pauly reagent) for phenols, amines and heterocyclic compounds which can couple. 

Tyrosine reacts, like histidine, with diazotized sulfanilic acid Pauly reagent). The coupled-... 

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