Which reagent is used to stain CSF for protein analysis in electrophoresis?

• A. Silver nitrate
• B. Coomassie Brilliant Blue
• C. Amido Black
• D. Lissamine Green

Answer: (A)

Staining after electrophoresis needs a reagent that can reveal very small amounts of protein, since CSF has low protein content. Silver nitrate–based silver staining provides high sensitivity, depositing metallic silver at protein sites and making even faint bands visible. This level of sensitivity is crucial for CSF analyses, where detecting subtle patterns can be clinically important (for example, oligoclonal bands). In contrast, Coomassie Brilliant Blue is less sensitive and may miss low-abundance CSF proteins; Amido Black is typically used in other contexts like membranes or blotting; and Lissamine Green isn’t used for visualizing proteins in electrophoresis. So the reagent used to stain CSF for protein analysis in electrophoresis is silver nitrate.