HP Yellow - 1 Quart

Hp Yellow is a Schiff-type reagent and is used to demonstrate aldehydes. Exposure to periodic acid prior to Hp Yellow stain oxidizes the hydroxyls in carbohydrates (mucin) to aldehydes. Hp Yellow combines directly with the aldehydes to form a stable covalent complex. Hp Yellow also bears a positive charge and stains everything in the tissue that is negatively charged. Acetic acid rinse in the procedure destains all ionically bound Hp Yellow, leaving the covalently bound mucus staining yellow. When used in combination with Hp Blue it produces results equivalent to the Alcian Yellow-toluidine blue procedure to demonstrate Helicobacter pylori. Negatively charged bacteria, nuclei and cytoplasm stain with the basic Hp Blue.