Decalcification Flashcards
widely used agents for routine decalcification
acid decalcifying agents
most common and fastest decalcifying agent?
recommended concn? range
nitric acid
5-10%
hastens decalcification by removing Ca ions from formic acid-containing decalcifying solns?
not recommended for fluids containing mineral acids such as? (2)
ion exchange resins
nitric acid and HCl
___ will serve to hasten decalcification
heat
Ca may bre removed by (4)
acid
chelating agents
ion exchange resins
electrophoresis
recommended for routine purposes to detect the presence of Ca in the decalcifying soln
chemical method/ Ca oxalate test
produre which Ca and lime salts are removed from tissue
decalcification
process which (+) charged Ca ions are attracted to a (-) electrode a d subsequently removed from the decalcifying soln
electrophoresis
recommended ratio of fluid to tissue vol for decalcification
20:1
very expensive but most ideal and reliable method of det the extent of decalcification?
NOT recommended for ___-fixed tissue?
x-ray or radiological method
hgcl
post decalcification for frozen section? temp?
wash in water or store in formol saline w/ 15% sucrose at 4 C
recommended temp for decalcification?
range?
room temp (18-30 C)
ideal time required for decalcifying tissue?
for dense bone tissue?
24-48 hrs
14 days
test done by touching or bending the tissue with fingers to det the consistency of tissue?
alternate method?
physical/mechanical test
pricking the tissue with fine needle or a probe
recommended for teeth and small pieces of bone (any of the 2)
von ebner’s fluid
formic acid
chemical test is performed on? vol? added to neutralize the fluid? color of litmus paper? this indicates that there is still Ca?
discarded fluid 5 mL strong ammonia red to blue cloudy
recommended for routine decalcification of post mortem research studies?
addition of ___ will accelerate decalcification?
formic acid
citrate
this is added after neutralization when the soln is still clear?
how long?
tap water may result into false +/- ?
0.5 mL of saturated aqueos soln of ammonium oxalate
30 mins
false postive
after decalcification, tissue is immersed in? any of the 2
other method for post decalcification?
how long for small specimens?
larger specimens?
saturated lithium carbonate soln/5-10% aqueos Na bicarbonate soln for several hrs
water rinsing/runningwater
30 mins
1-4 hrs
can be used both fixative and decalcifying agent? (2)
formic acid
chromic acid/flemmings fluid
what to do when the tissue is decalcified in EDTA?
whatll form if directly placed to dehydrating agent?
store in formol saline overnight
residual EDTA to presipitate
thickness of ion exchange resin spread over the bottom of container?
1/2 inch
tissue will undergo complete digestion within 24-48 hrs at wgat temp
55 C
most common chelating agent?
comercial name?
recommended pH?
EDTA
versene
7-7.4
procedure should be done after fixation and before impregantion
decalcification
very weak decalcifying soln suitable only for minute pieces of bone
sulfurous acid
most rapid decalcifying agent and is recommended for urgent works
phloroglucin-nitric acid
