Which dye stains proteins present in blood to produce a blue-black product?

The dye that stains proteins present in blood to produce a blue-black product is Amido Black. This particular dye is known for its ability to interact specifically with protein materials, binding to the amino acid residues and resulting in a distinctive coloring that aids in the visualization of latent prints at crime scenes or during forensic investigations. Its effectiveness at providing a clear contrast makes it valuable for detecting proteinaceous substances.

Amido Black is frequently utilized in forensic science because it offers a straightforward method for identifying and documenting fingerprints, especially when other methods may not be applicable. The blue-black product formed due to the dye’s reaction with proteins allows for easier analysis and enhances the ability to capture latent prints for further examination.