Бромфеноловый синий химические свойства, назначение, производство
Химические свойства
Bromophenol Blue is pink or red powder, soluble in ethanol, benzene, ether and other organic solvents, slightly soluble in water, the aqueous solution is yellow, and blue-purple in alkaline solution. It is mainly used as an acid-base indicator, the pH discoloration range is 3.0 to 4.6, and the color changes from yellow to green to blue-violet.
Подготовка
Bromophenol Blue is prepared by slow addition of excess bromine to a hot solution of phenolsulfonphthalein in glacial acetic acid.
Synthesis steps: Dissolve phenol red in glacial acetic acid, add a solution of bromine in glacial acetic acid with stirring, pour into 60°C hot water after stirring for a few minutes, cool to room temperature, and place overnight. Filter, wash the filter cake with glacial acetic acid and benzene in turn, and air dry to obtain bromophenol blue.
Определение
ChEBI: Bromophenol blue is 3H-2,1-Benzoxathiole 1,1-dioxide in which both of the hydrogens at position 3 have been substituted by 3,5-dibromo-4-hydroxyphenyl groups. It is used as a laboratory indicator, changing from yellow below pH 3 to purple at pH 4.6, and as a size marker for monitoring the progress of agarose gel and polyacrylamide gel electrophoresis. It has also been used as an industrial dye. It has a role as a two-colour indicator, an acid-base indicator and a dye. It is a sultone, an arenesulfonate ester, a 2,1-benzoxathiole, a member of phenols and an organobromine compound.
Методы очистки
Crystallise the dye from *C6H6 or Me2CO/AcOH, and dry it in air. It is an indicator: at pH 3.0 it is yellow and it is purple at pH 4.6. [Beilstein 19/3 V 458.]
Бромфеноловый синий препаратная продукция и сырье
сырьё
препарат