Stain reagent kit

for histopathologyCryptococcus neoformans

Alcian blue (pH 2.5) stain is intended for the staining of acid mucous substances, identification of mucous epithelioma and mucous substances in tumor as well as staining of Cryptococcus neoformans capsules. Principle: Alcian blue is the most specific stain to detect acid mucous substances. This anion dye forms an electrovalent bond with acid group. Alcian blue can be used to separate and identify different mucous substances at various pHs. At pH 1, sulfonic group (OSO3H) is stained; and at pH 2.5, carboxyl group is well stained. The capsule of Cryptococcus neoformans consists of mucous substance and can be stained blue with Alcian blue. Other mildews and their capsules cannot be stained. Methods: 1. Fix tissues in 10% formaldehyde. Dehydrate in typical manner and embed. 2. Deparaffinize sections to deionized water. 3. Place in Alcian blue solution for 10~20 minutes and rinse briefly with water. 4. Counterstain in Nuclear Fast Red solution for 5~10 minutes and rinse briefly with water. 5. Dehydrate in typical manner and clear. Mount with mounting media. Precaution: 1. Alcian blue solution contains 3% acetic acid to maintain pH at 2.5. Thymol is used as a preservative for mildew prevention. Alcian blue solution and Nuclear Fast Red solution should be stored at 4℃ after constitution. 2. The Alcian blue solution is a strong stain with stable color. Overstaining is not a concern even after long staining.