Decalcifying Solution, Formic Acid/Formalin

Product Options:

Part # 10493B 1 L $25.20
Part # 10493C 1 gal $68.90

 

SOLUTION:                                                                                                       

Part 10493B Part 10493C
Decalcifying Solution, Formic Acid/Formalin 1 liter 1 Gallon

 

Additionally Needed:

Decalcification End Point Set  Part 1051

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

 

APPLICATION:

Newcomer Supply Decalcifying Solution, Formic Acid/Formalin combines bone decalcification and fixation into a one-step time saving process.  This solution provides good cellular morphology preservation with a moderate rate of decalcification that is designed for light bone specimens such as sinus contents and disc material.  It is not recommended for femoral head and long bone sections.

 

DECALCIFYING SOLUTION FORMIC ACID/FORMALIN METHOD:

Fixation:  Separate fixation is not required.

Technique:  Paraffin sections cut at 5 microns on adhesive slides

Solutions:  All solutions are manufactured by Newcomer Supply, Inc.

 

PROCEDURE:

  1. Submerge bone segment(s) in container of Decalcifying Solution, Formic Acid/Formalin that adequately covers the specimen. A 20:1 ratio is recommended.
  1. See Procedure Notes #1 and #2.
  1. Check the specimen regularly for adequate solution coverage at routine intervals during the fixation/decalcification process for optimal reaction.  Decalcification time will vary and is dependent on size and weight of bone.
  1. Check light bone samples every 1 to 2 hours.
  2. Light bone specimens, on the average, will fix and decalcify in 4 to 6 hours.
  1. Check completion of decalcification with Decalcification End Point Set (Part 1051) regularly to deter over-decalcification and loss of cellular morphology.
  1. See Procedure Note #3.
  1. Wash the specimen in running tap water when decalcification is judged to be complete.  Suggested time for small samples is 30-60 minutes; larger bones 1-4 hours or according to laboratory protocol established times.
  1. Additional trimming of decalcified bone can occur at this stage to a size and thickness suitable for tissue processing.
  1. Proceed with laboratory tissue processing procedure for bone specimens.
  2. Trim block(s) and section the processed, paraffin embedded bone; if block trimming or sectioning is impaired due to bone hardness, surface decalcification is recommended.
  1. See Procedure Note #4.
  1. Perform surface decalcification by soaking the paraffin block with exposed tissue surface side down in recommended decalcifying solution for 15-60 minutes. Rinse block thoroughly with distilled water to remove corrosive acids and re-section.
  1. See Procedure Note #5.


PROCEDURE NOTES:

  1. Decalcification/fixative solution should be in contact with all specimen surfaces.  If multiple pieces are in one container, ensure that pieces are separated and/or suspended and not in direct contact or stacked on top of each other.  Change the solution at least daily and never add to or mix fresh solution with old.
  2. Fixation/decalcification can be enhanced with the use of low speed agitation with either a stir bar/stir plate or rotator/shaker.
  3. Decalcification end-point testing can also be accomplished through specimen radiography. Physical testing (probing or bending) of the bone is not recommended.
  4. Decalcifying Solution, Formic Acid/Formalin is not a preferred product for surface decalcification.  Decalcifying Solution, Formic Acid 5%, Aqueous (Part 1049) and Decalcifying Solution, Formic/Citrate (Part 10492) are the recommended products for optimal surface decalcification.
  5. Surface decalcification removes only a thin layer of residual calcium from the tissue block surface.  This will allow only a few calcium-free sections to be obtained. Repeating the surface decalcification process for additional sections may be required.

 

REFERENCES:

  1. Bancroft, John D., and Marilyn Gamble. Theory and Practice of Histological Techniques. 6th ed. Oxford: Churchill Livingstone Elsevier, 2008. 338-343.
  2. Luna, Lee G. Manual of Histologic Staining Methods of the Armed Forces Institute of Pathology. 3rd ed. New York: Blakiston Division, McGraw-Hill, 1968. 6-11.
  3. Urban, Ken. “Routine Decalcification of Bone.” Laboratory Medicine 12.4 (1981): 207-212.
  4. Villanueva, Anthony. “Experimental Studies in Demineralization and Its Effects on Cytology and Staining of Bone Marrow Cells.” The Journal of Histotechnology 9.3 (1986): 155-161.
  5. Modifications developed by Newcomer Supply Laboratory.