Coverslipping

Question 1

T/F hematoxylin is a dye

Answer 1

F - it must be oxidized to form hematein which is the dye

Question 2

how does chemical oxidation work

Answer 2

using sodium iodate to convert hematoxylin to hematein

Question 3

does natural or chemical oxidation have a longer shelf life

Answer 3

natural

Question 4

why are all hematoxylin used at low pH

Answer 4

suppress non nuclear staining

Question 5

what pH is hematoxylin

Answer 5

pH ~ 2.5

Question 6

what color does alum hematoxylin stain nucleus

Answer 6

brick red to purple when washed in alkaline solution (bluing)

Question 7

what are good bluing agents

Answer 7

lithium carbonate, dilute ammonia, Scott’s tap watear

Question 8

what is a disadvantage of alum hematoxylin

Answer 8

decolorize by acidic soultions = cannot do masson trichrome

Question 9

special ingredients in Gill hematoxylin

Answer 9

aluminum sulfate mordant
ethylene glycol solvent

Question 10

what is significant about Gill hematoxylin

Answer 10

alcohol free and stains goblet cells

progressive stain

Question 11

special ingredients in Harris hematoxylin

Answer 11

absolute ethyl alcohol solvent

Question 12

what is significant about Harris hematoxylin

Answer 12

used to be used with mercury

regressive stain

Question 13

special ingredients in Mayers hematoxylin

Answer 13

citric acid
chloral hydrate preservative

Question 14

what is significant about Mayers hematoxylin

Answer 14

alcohol free

progressive OR regressive

Question 15

special ingretiants in Erlich hematoxylin

Answer 15

glycerol preservative
acetic acid

Question 16

what is significant about Erlich hematoxylin

Answer 16

naturally oxidized

regressively

Question 17

special ingredients in Delafield hematoxylin

Answer 17

glycerol presrvative

Question 18

what is significant about Delafield hematoxylin

Answer 18

naturally oxidized

regressively

Question 19

what is iron used as in iron hematoxylin

Answer 19

mordant and oxidizer

Question 20

what is the most common iron hematoxylin

Answer 20

weigerts hematoxylin

Question 21

how is weigerts hematoxylin prepared

Answer 21

fresh using solution A and B

A- hematoxylin
B - iron with HCL

Question 22

difference in staining between iron and alum hematoxylin

Answer 22

iron can only be use PROgressivly

alum is for both

Question 23

disadvantage of iron hematoxylin

Answer 23

time consuming set up and prolonged staining

Question 24

What is thymol used for

Answer 24

control microbes in Eosin

Question 25

what is used to adjust pH of eosin

Answer 25

acetic acid

Question 26

what pH should eosin be at for best staining

Answer 26

4.5- 5

Question 27

what does phloxine B and eosin do

Answer 27

more vivid shades of red

Question 28

what does an HPS (hematoxylin, phloxine, saffron) stain do

Answer 28

differentiating yellow collagen from muscle and cytoplasm (red)

Question 29

where can sections be lost during staining

Answer 29

bluing if agitated

Question 30

cause for pale hematoxylin

Answer 30

less time old stain over differentiated

Question 31

cause of dark hematoxylin

Answer 31

too long under diff

Question 32

cause for pale eosin

Answer 32

pH too high from bluing agent - add acetic acid less time prolonged dehydration

Question 33

cause for dark eosin

Answer 33

pH too low - add NaOH too long too low time in dehydration

Question 34

less than 3 shades of red

Answer 34

too low time in dehydration

Question 35

artifact

Answer 35

did not filter hematoxylin

Question 36

purpose of coverslip

Answer 36

presrve stained tissue, protect, focus at high powers

Question 37

what is the refractive index of resinous mounting media

Answer 37

1.5

Question 38

when is aqueous mounting media used

Answer 38

when fat in tissue will be dissolved in xylene

Question 39

disadvantage of aqueous mounting media

Answer 39

low refractive index = less focus on high power not permanant bleeding of stains

Question 40

what helps aqueous mounting media from bleeding

Answer 40

adding sugars

Question 41

what happens when a slide dries before coverslipping

Answer 41

corn flaking = forms brown articfact

Question 42

cause of water droplet on stained s ection

Answer 42

low time dehydrating clearing agent (xylene) contaminated w water

Question 43

cause of unfocussed parts of slide

Answer 43

mounting media on top