Decalcification Flashcards
What is removed during decalcification?
Calcium salts
4 types of decalcification
Acids
Chelating agents
Ion-exchange resins
Electrolytic method
Recommended for urgent biopsies; develops a yellow discoloration
Nitric acid (5-10%)
Recommended for post-mortem and research tissues
Formic acid (5%)
Recommended for research purpose, bone marrow, and autopsy tissues
Formic acid-Sodium citrate solution
Recommended for urgent biopsies
Hydrochloric acid (1%)
Recommended for small spicule of delicate tissues
Trichloroacetic acid (5%)
Does not require washing out because excess acid may be removed by several changes of 90% OH thus improving tissue dehydration
Trichloroacetic acid (5%)
A weak decalcifying agent not used for dense tissue
Trichloroacetic acid (5%)
Recommended for routin purpose; for minute bones
Chromic acid (Flemming’s fluid)
Used as both decalcifying and fixing agent
Chromic acid (Flemming’s fluid)
Inhibits nuclear staining with hematoxylin
Chromic acid (Flemming’s fluid)
Undergoes reduction and forms precipitate at the bottom of the container thus requiring frequent changes of the solution
Chromic acid (Flemming acid)
Recommended for routine work; decalcifies and softens bones at the same time
Perenyi’s fluid
Substances that combine with calcium ions and other salts to form weakly dissociated complexes and facilitate removal of calcium salts
Chelating agents
Recommended for detailed microscopic studies
Chelating agents
Decal agent consisting of a solution of a chelating agent in dilute HCl
Cal-Ex
Combines with calcium and forms non-ionized complexes
Versene (EDTA)
An ammonium form of polystyrene resin added to the decalcifying solution that speeds up decal process
Ion-exchange resin
Common choice of decal agent that ion-exchange resin is added to
Formic acid
Process where insoluble calcium salts in bone are changed to an ionizable salt and acid
Electrolytic method
In the electrolytic method for decal, calcium ions migrate to the _________
Cathode
Recommended for small fragments of bones
Electrolytic method
Most ideal and most reliable method for determining complete decal
X-ray/radiological test
3 tests for complete decal
Physical/Mechanical test
X-ray/radiological test
Chemical test
Complete removal of calcium salts from tissues following fixation
Decalcification
