Educational Outline

Mucicarmine

A stain that highlights acidic mucins in pink-red, useful for mucinous tumors and Cryptococcus detection.

Author: Kelsey Goldman, HTL (ASCP)

Last Update: 7 March 2025

Copyright: 2025, HistologyOutlines.com

Cite this Page! -> Goldman, Kelsey. “Alcian Blue.” HistologyOutlines.Com, 6 March 2025. Accessed (today).

Purpose

  • Mucicarmine is a stain used to demonstrate epithelial mucins in tissue (Carson, 2001).

Control Tissues

  • Provide examples of control samples for validation.
  • Include criteria for selecting appropriate controls.

Staining Pattern

  • Mucin- Rose to Red
  • Nuclei- Black
  • Other- Yellow or Blue

Biochemistry Theory

  • The mucicarine solution is composed of several agents, including aluminum and carmine. When combined in the stock solution these two compounds form a chelation complex. This complex has a net positive charge and therefore is attracted to the negatively charged acid groups found in the mucins of the epithelia (Carson, 2001).
    • There are 4 very important points to remember about mucins:
      Mucins are stained with basic dyes.
      Mucin staining is metachromatic.
      Mucins are precipitated by acetic acid (except gastric mucins).
      Mucins are soluble in alkaline solutions. (Carson, 2001)
    .

Troubleshooting

  • It is important to follow the instruction of the metanil yellow and weigerts iron hematoxylin. The staining of the mucins will not be visible if these tow elements are overstained (Carson, 2001).

Additional References

  • Carson, F. L. (2001). Histotechnology: a self-instructional text (2. ed., [Reprint]). ASCP Press. .

Sample Protocol

    Protocol Adapted from Carson’s

    Reagents:

    • Mucicarmine Solution (diluted as prescribed on the bottle)
    • Weigert Iron Hematoxylin
    • Metanil Yellow Solution 0.25%

    Method:

    1. Deparaffinize and rehydrate.
    2. Place in Weigert’s Iron Hematoxylin for 7 minutes.
    3. Wash in running tap water for 10 minutes.
    4. Place in the working mucicarmine solution for 1 hour.
    5. Rinse quickly in DIH2O, shake off excess water.
    6. Counterstain in Metanil Yellow for 30 seconds to 1 minute.
    7. Run through graded alcohols to xylene and coverslip with a xylene-based mounting media.