ACID FAST STAINING

Question 1

what materials are needed for acid fast staining procedure

Answer 1

1. Microscope slide
2. Bacterial sample (usually sputum or tissue)
3. Bunsen burner (or other heat source)
4. Forceps
5. Staining tray or staining coplin
6. Carbol fuchsin stain (phenol-based)**
7. Acid-alcohol (usually 3% 8.hydrochloric acid in 95% ethanol)
8. Methylene blue counterstain
   Water
9. Bibulous paper (or blotting paper)

Question 2

what is the first step in acid fast staining

Answer 2

smear preparation

Question 3

what happens in smear preparation

Answer 3

1. Add a loopful of sterile water to a clean slide.
2. Transfer a small amount of your sample to the water on the slide and mix gently with the loop.
3. Spread the mixture to create a thin smear across the slide surface.
4. Allow the smear to air dry completely

Question 4

what step follows after smear preparation and what is its significance

Answer 4

Heat fixation.

Question 5

what is the first solution used in acid fast staining

Answer 5

Carbol fuchsin stain (slide is flooded with this stain)

Question 6

what follows after carbol fuchsin staining

Answer 6

heating (5 to 10 minutes) either by steam method or hot plate method

Question 7

what follows after heating

Answer 7

rinse with water

Question 8

after heating and rinsing with water what follows next

Answer 8

Decolorization for 15 to 30 seconds. this removes carbol fuchsin from non-acid fast bacteria
(rinse to stop decolorization)

Question 9

what is the counterstain used in acid fast

Answer 9

methylene blue for 1-2 minutes.

Question 10

what is the significance of methylene blue

Answer 10

This stains non-acid-fast bacteria blue for better contrast.

Question 11

what follows after counterstaining

Answer 11

rinse with water and then drying and observe

Question 12

mention two acid fast bacteria

Answer 12

mycobacterium tuberculosis (TB)
Mycobacterium leprae