Tetrabromphenol blue

The dipstick test for total protein includes a cellulose test pad impregnated with tetrabromphenol blue and a citrate pH 3 buffer. The reaction is based on the protein error of indicators phenomenon in which certain chemical indicators demonstrate one color in the presence of protein and another in its absence. Thus tetrabromphenol blue is green in the presence of protem at pH 3 but yellow in its absence. The color is read after exactly 60s and the test has a lower detection limit of 150 to 300mg/L, depending on the type and proportions of protein present. The reagent is most sensitive to albumin and less sensitive to globulins, Bence Jones protein, mucoproteins, and hemoglobin. 

Tetrabromphenol blue Tetrabromophenoltetrabromo- sulfonephthalein 3.0-4.6 yellow - blue Harden and Drake... 

It has already been stated that tetrabromophenoltetrabromo-sulfonephthalein (tetrabromphenol blue) is a good substitute for bromphenol blue because it changes from yellow to pure blue and exhibits no dichromatism. 

Methyl orange, Bromphenol blue, and Tetrabromphenol blue. Acid solution in about 0.01 N hydrochloric acid alkaline solution in a liquid with pH > 5. 

Tetrabromphenol blue, sodium salt 3.0. 6 Aqueous Yellow Blue... 

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