GPHT LAB - Clearing Flashcards
in dealcoholization, tissue section is immersed in __
ante-medium
raises the refractive index of the tissue
ante-medium
clearing agents must be miscible with both __
alcohol and paraffin wax
does not cause to much brittleness
benzene
best routine clearing agent
benzene
can cause aplastic anemia
benzene
used for large, thick, hard tissues
chloroform
slow acting
toxic to liver
does not make tissues translucent
tissues tend to float
chloroform
used for cleaning knives
xylene
diluent in mounting medium
xylene
most common clearing agent
xylene
for tissues less than 5 mm
xylene
useful for paraffin embedding
xylene
becomes milky/turbid if water is still present (incomplete dehydration)
xylene
overclearing causes tissue to become
hard and brittle
sub for xylene
toluene
subs for xylene/benzene
toluene
for CNS, skin, smooth muscle, cytological work
cedar oil/cedar wood oil
can leave tissue for a very long time w/o dehydration
cedar oil/cedar wood oil
penetrates well = best clearing agent
cedar oil/cedar wood oil
expensive and turbid
cedar oil/cedar wood oil
SLOW
Makes tissue brittle
can be faked
clove oil
prevents clove oil from becoming brittle
oil of bergamot
does not extract aniline dyes
oil of bergamot
can be used with celloidin prep
oil of bergamot
spanish hop oil or thyme oil or mix
oil of origanum
dissolves out aniline dyes
oil of origanum
does not dissolve celloidin
oil of origanum
other names of oil of wintergreen
methyl salicylate, artificial oil
for delicate tissues bc hardening effect of alcohol can be avoided
oil of wintergreen
clearing time is indefinite
cedar oil/cedar wood oil
oil of wintergreen
must be soaked out by __ when oil of wintergreen is used for celloidin sections
chloroform/xylene
poor dehydrant, split by small amts of water
oil of wintergreen
oxidizes easily on standing
oil of wintergreen
must be soaked out by xylene or chloroform when used for celloidin sections
oil of wintergreen
for smooth muscles (2)
carbon disulfide
phenol
very inflammable with foul odor
carbon disulfide
subs of chloroform
carbon tetrachloride
adv of carbon tetrachloride
cheaper
for friable tissues
carbol-xylene
made by adding anhydrous crystals of phenol to xylene until no more dissolves
carbol-xylene
for moist and humid climates
carbol-xylene
corrosive
carbol-xylene
for cellular organs, friable tissues, skin, athermatous arteries, hard collagenous specimens
tetrahydrofuran
how many baths for THF
3
3 baths required
THF
colorless agents
xylene
THF
BP of THF
65C
FP of THF
-108.5C
Density of THF
0.8894
Wide-range solvent
Soluble in most solvents
THF
THF Forms __ with water
azeotrope
forms azeotrope with water
THF
Constant bp mixture (64C) consisting of 9% THF and 6% water
azeotrope
melted paraffin wax mixes with __ in all proportions
THF
superior to ordinary dehydrating agent
THF
shortens total prcessing time
THF
fumes may cause conjunctival irritation after about 6 mos
with offensive odor
THF
recommended for the eyes
terpineol
excellent clearing agent
High Test Aviation Lead-Free Gasoline
for double embedding techniques
methyl salicylate and methyl benzoate
cause the least hardening of tissues (3)
cedar oil, gasoline, petroleum ether
Suitable for large tissue specimens, tough tissues (e.g. Skin, fibroid, decalcified tissues), nervous tissues, lymph nodes, embryos
Chloroform
Does not extract aniline dyes
Can be used with celloidin
Oil of Bergamot
Dissolves aniline
Does not dissolve celloidin
Oil of Origanum
Possible Components of Oil of Origanum (3)
Spanish Hop Oil
Thyme Oil
Turpentine
How to make carbol-xylene
Add anhydrous crystals of phenol to xylene until no more dissolves
Composition of azeotrope
9% THF
6% water
THF may cause conjunctival irritation after how many months
6
Clears from 95% alcohol
Terpineol
Good for paraffin and celloidin work
But volatile
Phenol
