Papanicolaous hematoxylin according to Gill (PAP 1b) is a modified hematoxylin staining method used in Papanicolaou staining (PAP staining). PAP staining is a multistage staining technique mainly used for cytological examination of cells in body fluids, especially in the field of gynecological cytology for cervical smears.
In PAP staining, Gill's Papanicolaous Hematoxylin (PAP 1b) serves as the core stain that stains cell nuclei and basophilic structures. It is a modified version of Gill hematoxylin solution optimized for Papanicolaou staining. PAP staining involves several steps, including the application of orangephilic and eosinophilic dyes to visualize various cell structures and cytoplasmic components for detailed examination and diagnosis.