Congo Red Stain Set, Bennhold, Amyloid

Newcomer Supply Beaker

Solution A: Congo Red Stain 1%, Aqueous   500 ml
Solution B: Alkaline Alcohol   500 ml

Product Options:

Part # 1038A 500 ml set $88.50 H

SET INCLUDES:

Part 1038A
Solution A: Congo Red Stain 1%, Aqueous 500 ml
Solution B: Alkaline Alcohol 500 ml

 

Additionally Needed:

Amyloid, Animal Control Slides
              OR
Amyloid Control Slides
Part 4031
    OR
Part 4030
Xylene, ACS Part 1445
Alcohol, Ethyl Denatured, 100% Part 10841
Alcohol, Ethyl Denatured, 95% Part 10842
Hematoxylin Stain, Mayer Modified Part 1202
Coplin Jar, Plastic Part 5184 (for microwave modification)

 

For storage requirements and expiration date refer to individual product labels.

 

APPLICATION:

Newcomer Supply Congo Red Stain Set, Bennhold, Amyloid, with included microwave modification, is used for identifying extraneous protein deposits in amyloidosis.  The use of polarizing lenses is essential for visualizing amyloid positive areas or confirm negativity.

 

METHOD:

Fixation: Formalin 10%, Phosphate Buffered (Part 1090)
Technique:  Paraffin sections cut at 8 microns
Solutions:  All solutions are manufactured by Newcomer Supply, Inc.

All Newcomer Supply Stain Sets are designed to be used with Coplin jars filled to 40 ml following the provided staining procedure. Some solutions in the set may contain extra volumes.

 

STAINING PROCEDURE:

    1. If necessary, heat dry tissue sections/slides in oven.
    2. Deparaffinize sections thoroughly in three changes of xylene, 3 minutes each. Hydrate through two changes each of 100% and 95% ethyl alcohols, 10 dips each.  Wash well with distilled water.
        1. See Procedure Notes #1 and #2.
    3. Place slides in Solution A: Congo Red Stain 1%, Aqueous; 1 hour.

        Microwave Modification: See Procedure Note #3.

        1. Place slides in a plastic Coplin jar (Part 5184) containing Solution A: Congo Red Stain 1%, Aqueous. Microwave for 3 minutes at 70°C.
    1. Rinse in two to three changes of tap water; rinse in distilled water.
    2. Differentiate in Solution B: Alkaline Alcohol, 5 to 30 seconds, agitating constantly until slide background is cleared of Solution A: Congo Red Stain 1%, Aqueous.
    3. Rinse in two to three changes of tap water; rinse in distilled water.
    4. Counterstain with Hematoxylin Stain, Mayer Modified (Part 1202), 3-5 minutes.
    5. Wash in running tap water for 5 to 10 minutes.
    6. Dehydrate in two changes each of 95% and 100% ethyl alcohol. Clear in three changes of xylene, 10 dips each; coverslip with compatible mounting medium.

 

RESULTS:

Light Field Microscopy:
Amyloid Pink to red
Nuclei Blue
Polarized Light:
Amyloid fluorescence Apple green

 

PROCEDURE NOTES:

    1. Drain slides after each step to prevent solution carry over.
    2. Do not allow sections to dry out at any point during procedure.
    3. The microwave procedure was tested using a laboratory-grade microwave oven. This procedure is a guideline and techniques should be developed for use in your laboratory.
    4. For optimal results sections should be cut at 8 microns to provide more intense staining and allow smaller amyloid deposits to be identified.
    5. If using a xylene substitute, follow manufacturer’s recommendation for deparaffinization and clearing steps.

 

REFERENCES:

    1. Luna, Lee G. Histopathologic Methods and Color Atlas of Special Stains and Tissue Artifacts. Gaitheresburg, MD: American Histolabs, 1992. 366-367.
    2. Sheehan, Dezna C. and Barbara B. Hrapchak. Theory and Practice of Histotechnology. 2nd ed. St. Louis: Mosby, 1980. 177-178.
    3. Modifications developed by Newcomer Supply Laboratory.