BioGnost’s Hematoxylin HP, Pap 1A is one of formulations of hematoxylin used in cytology for a more precise nuclear cell staining. Unlike Hematoxylin H which is used in histology, Hematoxylin HP, Pap 1A is ideal for intensive staining cytology smears using progressive and regressive methods. Hematoxylin is extracted from logwood (Haematoxylon campechianum L.). Hematoxylin oxidates to hematein and binds with metal ions (mordants), hematein turns into irreplaceable nuclear dye. Positively charged hematein-mordant complex then binds with negatively charged phosphate ions of the DNA’s nucleus, creating characteristic blue coloration. BioGnost’s Hematoxylin HP, Pap 1A is a specific hematoxylin solution used for staining chromatins of both normal and abnormal cytology smears. They stain nuclear membrane, nucleoplasm and nucleolus exceptionally well. Test samples can be gynecological and non-gynecological, such as sputum, urine, and cytological puncture samples. In order to obtain optimal staining results, BioGnost’s Hematoxylin HP, Pap 1A properties are completely in accordance with other BioGnost’s reagents used for cytological staining acc. to Papanicolaou – OG-6, Pap 2A reagent, EA 31, Pap 3A reagent, as well as alternative counterstain polychromatic stains, such as EA 50, Pap 3B reagent, EA 65, Pap 3C reagent, and EA 65, Pap 3D reagent.