DEHYDRATION Flashcards
the process of removing intercellular and extracellular water from the tissue
dehydration
ratio of dehydrating agent to tissue
10:1
dehydration is done at what temp?
room temp
routine tissue alcohol grades:
70 - 95 - 100
delicate tissue alcohol grades:
30 onwards
alcohol conc above 80% will make tissues:
hard, brittle, and difficult to cut
alcohol conc below 70% will make tissues:
wither or macerated
this reagent ensures complete dehydration and removes water from the dehydrating fluid
anhydrous copper sulfate
what does blue discoloration of copper sulfate means?
there is still presence of water
BEST dehydrating agent
ethanol
dehydrating agent for blood and tissue films
methanol
dehydrating agent for plant and animal micro-techs
sweet and rancid odor
butanol
universal solvent
tertiary butanol
best clearing agent for microwave tech
isopropanol
dehydrating agent used for most urgent biopsies; also a fixative
acetones
the excellent universal solvent
dioxane
method that uses pure dioxane and paraffin wax
graupners
method that uses dioxane quicklime
weisebergers
dehydrating agent that can be stored for months with no hardening or distortion
combustible at 110-120 F
highly toxic
cellosolve
dehydrating agent that removes water very readily
triethyl phosphate
dehydrating agent that does not dissolve aniline dyes
have ether like odor
tetrahydrofuran
3 universal solvents
tertiary butanol
dioxane
tetrahydrofuran
typical dehydration sequence for <4mm thick sections
70% ethanol - 15 min 90% ethanol - 15 min 100% ethanol - 15 min 100% ethanol - 15 min 100% ethanol - 30 min 100% ethanol - 45 min
additives:
acts as tissue softeners
4% phenol + each 95% ethanol baths
