Bromocresol green reagent

Heat reagent-grade material for 1 hr at 255-265°C. Cool in an efficient desiccator. Titrate sample with acid to pH 4-5 (first green tint of bromocresol green), boil the solution to eliminate the carbon dioxide, cool, and again titrate to pH 4-5. Equivalent weight is one-half the formula weight. 

Bromocresol Green — Bromophenol Blue — Potassium Permanganate Reagent... 

Bromocresol Green—Bromophenol Blue—Potassium Permanganate Reagent 229... 

Buffered Indicator Solution Prepare a mixture consisting of 700 mL of 0.1 M citric acid (anhydrous, reagent grade), 200 mL of 0.2 M disodium phosphate, and 50 mL each of 0.2% bromophenol blue and of 0.2% bromocresol green in spectrograde methanol. 

Bromocresol Green—Bromophenol Blue—Potassium Pemumganate Reagent... 

The indicators were obtained from Kodak Laboratory Chemicals, Aldrich Chemical Company, and J.T. Baker and were used without further purification. The indicators employed in the majority of the titrations were bromocresol green and bromothymol blue each of which exhibits two acid-base transitions at Pka = -3.7, +4.6, and -1.5, +6.8, respectively(20, 22, 26) The medium for the titration and electrophoretic mobility experiments was benzene (Burdick and Jackson Laboratories) having a water content of less than 0.03 percent. The base used as titrant was n-butylamine, Baker analyzed reagent grade. 

Visualization Technique A Ultraviolet Light B Potassium lodoplatinate Reagent C Bromocresol Green Spray... 

Colored reagents (methyl orange, phenolphthalein and bromocresol green) mixed with CDs would result in an increase or decrease of maximum absorbency, and there is a linearity relation between absorbency and concentration of CDs in the certain range. Thus, UV-spectrophotometry method is widely used for quantitative analysis of CDs. 

The contents of a-, fS- and y-CDs are measured by UV-spectrophotometry using methyl orange, phenolphthalein and bromocresol green as color reagents, respectively. The detection conditions are as follows ... 

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