To cytochemically demonstrate the total proteins in the ciliates using Mercuric Bromophenol Blue (MBB).
Carnoy's fixed ciliates on slides
All glassware and plastic ware used should be sterilized:
Solutions of short chain alcohols and acetic acid have been commonly used for fixing proteins as insoluble aggregates within gel matrix. The combination of low pH and high organic solvent content disrupts the hydrogen bonding which holds protein structures together, and exposes hydrophobic portions of the protein core. Bromophenol Blue is used as an acid-base indicator, a color marker and a dye within the range between pH 3.0 and 4.6. It changes from yellow at pH 3.0 to blue or purple after pH 4.6; this reaction is reversible. Bromophenol Blue acts as an acidic dye in aqueous medium and is capable of reacting with the basic reactive groups. The acidic groups of the dye react with basic groups of the protein to give blue colour.
Solutions of short chain alcohols and acetic acid have been commonly used for fixing proteins as insoluble aggregates within gel matrix. The combination of low pH and high organic solvent content disrupts the hydrogen bonding which holds protein structures together, and exposes hydrophobic portions of the protein core. Bromophenol Blue is used as an acid-base indicator, a color marker and a dye within the range between pH 3.0 and 4.6. It changes from yellow at pH 3.0 to blue or purple after pH 4.6; this reaction is reversible. Bromophenol Blue acts as an acidic dye in aqueous medium and is capable of reacting with the basic reactive groups. The acidic groups of the dye react with basic groups of the protein to give blue colour.
Animation of the experiment:--
Click here to perform the simulation
The cells stain blue, showing the presence of protein.