2. How Are Stains Classified?
Stains are classified based on the pH of their chromophore (color bearing ion) into acidic, basic and neutral. Acidic dyes have anionic chromophore eg.. sodium+ eosinate-. Basic dyes have cationic chromophore eg.. metFiylene blue+ chloride-. Acidic dyes combine more strongly with cytoplasmic components of bacteria, especially the nucleus that is basic in nature. Neutral dyes have both acidic and basic component that nullity each other.
