Aluminum Hematoxylin Solutions

Question 1

recommended for progressive staining of tissues

Answer 1

Aluminum (alum) hematoxylin stains

Question 2

adequately stain the nuclei but leave the background tissue relatively unstained, to be later counterstained with

Answer 2

eosin
Congo red
safranin

Question 3

section overstained -> differentiated in acid alcohol -> “blueing”

Answer 3

regressive staining

Question 4

Aluminum salts give a _____ & ↑ selectivity for nuclei

Answer 4

blue lake

Question 5

Two main alum hematoxylin solutions

Answer 5

Ehrlich’s hematoxylin
Harris hematoxylin

Question 6

Rapid ripening of Ehrlich’s reagent

Answer 6

sodium iodate

Question 7

Ripening of Harris solution

Answer 7

mercuric chloride

Question 8

Excess acid: aluminum hydroxide cannot be formed -> with ultimate failure of aluminum hematoxylin dye-lake to form, due to lack of -OH ions. Acid solutions of alum hematoxylin become

Answer 8

red

Question 9

During staining, alum hematoxylin-stained sections are usually passed on to an alkaline solution (e.g. 1% hydroxide) in order to neutralize the acid and free the OH group, to form an insoluble blue aluminum hematin-tissue-lake -> termed as

Answer 9

blueing

Question 10

commonly used for sufficiently alkalike

Answer 10

warm (40° to 50°C) tap water

Question 11

When tap water is not sufficiently alkaline, or is even acid, and is unsatisfactory for blueing hematoxylin -> use

Answer 11

lithium carbonate
bicarbonate
potassium/sodium acetate

Question 12

accelerates blueing of thin paraffin sections

Answer 12

Scott’s Tap Water Substitute

Question 13

used to blue stains

Answer 13

Ammonia water

Question 14

tendency to form crystalline deposits unless the slides are agitated in it and washed well afterwards

Answer 14

Lithium carbonate

Question 15

very cold water

Answer 15

slows down the process

Question 16

warming

Answer 16

accelerates

Question 17

Use of very cold water (below 10°C) for blueing sections:

Answer 17

pink artifact discolorations