Product Description: Fast blue bb salt (hemi(zinc chloride) salt is a water-soluble dye commonly used as a histological stain in various biological applications such as staining cellular components or detecting enzyme activity. Fast blue BB salt has a unique Chemical properties that allow it to bind to specific proteins to form a blue product that can be detected by microscopy or spectrophotometry. This makes it a useful tool for visualizing and quantifying target proteins in tissue samples or cell cultures.