Decalcification - MIDTERM Flashcards
Recommended fixative prior to decalcification is _______
buffered formalin
WHAT SPECIMEN?
Use Zinc formalin, Lilies B5, Formol-acetic alcohol (Davidson Fixative) or Bouin’s
bone marrow specimen
What fixative should never be used prior to decalcification?
Carnoy’s – may cause extreme chemical toxicity
DECALCIFICATION
Ideal thickness must be ______
1-3 mm
Ratio of fluid to tissue is _____, the volume of the decalcifying agent must be 10-20x of the specimen
20:1
Optimal Temperature for decalcification is _______
Room Temperature (RT)
Auto Technicon can only perform the first four steps of tissue processing such as _____, _____, _____, and ______
fixation, dehydration, clearing and infiltration
Auto Technicon cannot do decalcification, we do decalcification _______
manually
The positively charged calcium ions are attached to negative electrodes from the decalcifying solution – facilitating calcium removal
electrolytic method
The most rapid because by electricity, calcium is removed
electrolytic method
Calcium is rapidly removed by the decalcifying solution containing formic acid, thereby increasingly solubility from tissues
ion exchange resin
the process is longer than Electrolytic Method
ion exchange resin
duration for ion exchange resin
1-14 days
chelating agent
EDTA
very good anticoagulant, a potent anticoagulant
EDTA
As a potent agent, it is considered “weak”
EDTA
It is considered as the best decalcifier in electron microscopy, enzyme and immunohistochemistry (histochemical staining)
EDTA
remedy for EDTA
magnesium chloride
For small specimens- decalcification may be carried out for ______
1-3 weeks
For dense tissues- decalcification may be carried out for ______
6-8 weeks
EDTA must be changed every _______
3 days
nitric containing acids
5-10% Nitric Acid, Formol Nitric, Perenyi’s, Phloroglucin
most commonly used acid
nitric acid
For routine decalcification, most commonly used
10% aqueous nitric acid
duration of 10% AQUEOUS NITRIC ACID
24 hours
nitric acid + formaldehyde = ________
formol nitric acid
Double purpose
Requires fume hood if used
Duration is 1-3 days
formol nitric acid
Double purpose, can be used as decalcifying agent and tissue softener
Perenyi’s nitric, chromic acid and ethyl alcohol
duration time for Perenyi’s nitric, chromic acid and ethyl alcohol
2-7 days
Combining nitric acid + chromic acid +
ethyl alcohol = _______
Perenyi’s fluid
Phloroglucin + Nitric acid = _______
phloroglucin nitric
