H&E / Coverslipping

Question 1

T or F:
H&E is performed on all tissues?

Answer 1

True

wide variety of tissue features/components

Question 2

How many shades of pink should there be?

Answer 2

3:
light - connective tissue
med pink - muscle
dark pink/red - RBC

Question 3

Too much hematoxylin

Answer 3

Dark purple cast over cytoplam
lack of chromatin pattern

Question 4

Eosin Assessment

Answer 4

connective tissue - pink
muscle - med pink
RBC - dark pink/red

contrast between 2 stains

Question 5

Hematoxylin Assessment

Answer 5

Chromatin patterns present
pink cytoplasm
dark staining lymphocyte

contrast between 2 stains

Question 6

Hematoxyline must be: (2) prior to use

Answer 6

Oxidized into hematein to be functional
Mordanted - ferric iron or aluminum

Question 7

purpose of a “bluing” agent

Answer 7

Alkaline solution that changes Hematoxylin from pale red to blue-black

Question 8

Hematoxylin is a CATIONIC/ANIONIC dye

Answer 8

CATIONIC
stains negatively charged groups

phosphates - nuclear stain

Question 9

Where do we find hematoxylin in nature

Answer 9

Logwood tree

Question 10

eosin Y vs eosin B

Answer 10

Y - yellow
B - blue
ACIDOPHILIC dye

Question 11

preferred pH of Eosin

Answer 11

4.0-5.9
4.5

Question 12

Which hematoxylin demonstrates mucin

Answer 12

Gill’s

Question 13

what is responsible for the three shades of pink?

Answer 13

Eosin being solutble (but not cleared) in water and alcohol

Question 14

H&E maintenance

Answer 14

• filter daily
• rotate/replace dehydrating alcohol
• replace stains based on SLIDE VOLUME
• use of a control slide daily - any tissue will work

Question 15

Poorly stained hematoxylin

poorly defined nucleus/chromatin

Answer 15

• insufficient staining time
• over-differeniated with acid-alcohol
• old/expired stain
• insufficient bluing

Question 16

Hematoxylin stained too dark

little chromatin detail, purple cytoplasm

Answer 16

• prolonged staining time
• under-differentiated with acid alcohol

Question 17

Blue-purple precipitate on tissue

Answer 17

• failure to filter hematoxylin

Question 18

Eosin pale staining

Answer 18

• contam. with blue reagent (pH too high/alk)
• extended dehydration
• insufficient staining time
• old/expired stain

Question 19

Eosin staining too intense

Answer 19

• prolonged staining time
• insufficient time in dehydating alcohols
• pH too low (tech error)

Question 20

Less than 3 shades of eosin staining

Answer 20

• insufficient time in dehydating alcohol
• incorrect pH

Question 21

Purpose of coverslipping

Answer 21

protection from damage
focus under high magnification

Question 22

Mounting media

Answer 22

Resinous - polymers in organic solvent
Aqueous - for tissues that are soluble in organic solvents - simple syrups and preservatives

Question 23

T/F: tissue can dry before coverslipping?

Answer 23

FALSE
Drying artifact may occur