Coverslipping Flashcards
T/F hematoxylin is a dye
F - it must be oxidized to form hematein which is the dye
how does chemical oxidation work
using sodium iodate to convert hematoxylin to hematein
does natural or chemical oxidation have a longer shelf life
natural
why are all hematoxylin used at low pH
suppress non nuclear staining
what pH is hematoxylin
pH ~ 2.5
what color does alum hematoxylin stain nucleus
brick red to purple when washed in alkaline solution (bluing)
what are good bluing agents
lithium carbonate, dilute ammonia, Scott’s tap watear
what is a disadvantage of alum hematoxylin
decolorize by acidic soultions = cannot do masson trichrome
special ingredients in Gill hematoxylin
aluminum sulfate mordant
ethylene glycol solvent
what is significant about Gill hematoxylin
alcohol free and stains goblet cells
progressive stain
special ingredients in Harris hematoxylin
absolute ethyl alcohol solvent
what is significant about Harris hematoxylin
used to be used with mercury
regressive stain
special ingredients in Mayers hematoxylin
citric acid
chloral hydrate preservative
what is significant about Mayers hematoxylin
alcohol free
progressive OR regressive
special ingretiants in Erlich hematoxylin
glycerol preservative
acetic acid
what is significant about Erlich hematoxylin
naturally oxidized
regressively
special ingredients in Delafield hematoxylin
glycerol presrvative
what is significant about Delafield hematoxylin
naturally oxidized
regressively
what is iron used as in iron hematoxylin
mordant and oxidizer
what is the most common iron hematoxylin
weigerts hematoxylin
how is weigerts hematoxylin prepared
fresh using solution A and B
A- hematoxylin
B - iron with HCL
difference in staining between iron and alum hematoxylin
iron can only be use PROgressivly
alum is for both
disadvantage of iron hematoxylin
time consuming set up and prolonged staining
What is thymol used for
control microbes in Eosin
what is used to adjust pH of eosin
acetic acid
what pH should eosin be at for best staining
4.5- 5
what does phloxine B and eosin do
more vivid shades of red
what does an HPS (hematoxylin, phloxine, saffron) stain do
differentiating yellow collagen from muscle and cytoplasm (red)
where can sections be lost during staining
bluing if agitated
cause for pale hematoxylin
less time
old stain
over differentiated
cause of dark hematoxylin
too long
under diff
cause for pale eosin
pH too high from bluing agent - add acetic acid
less time
prolonged dehydration
cause for dark eosin
pH too low - add NaOH
too long
too low time in dehydration
less than 3 shades of red
too low time in dehydration
artifact
did not filter hematoxylin
purpose of coverslip
presrve stained tissue, protect, focus at high powers
what is the refractive index of resinous mounting media
1.5
when is aqueous mounting media used
when fat in tissue will be dissolved in xylene
disadvantage of aqueous mounting media
low refractive index = less focus on high power
not permanant
bleeding of stains
what helps aqueous mounting media from bleeding
adding sugars
what happens when a slide dries before coverslipping
corn flaking = forms brown articfact
cause of water droplet on stained s ection
low time dehydrating
clearing agent (xylene) contaminated w water
cause of unfocussed parts of slide
mounting media on top
