UNIT 2 ACID FAST STAINING Flashcards
Kinyoun mordant
TERGITOL
is used as the primary stain
Carbol fuchsin
kinyoun acid alcohol NAF
colorless
ACID FAST STAINING Principle:
Mycolic acid, once stained by the primary stain, is able to resist the decolorization of acid-alcohol rendering them as “ACID FAST”
ZIEHL-NEELSEN ACID-FAST STAINING PROCEDURE
- Cover smear with
carbolfuchsin. Steam over
boiling water for 8 minutes.
Add additional stain if the
stain boils off. - After the slide has cooled,
decolorize with acid-alcohol
for 15-20 seconds. - Stop decolorization action of
acid-rinsing briefly with
water. - Counterstain with methylene
blue for 30 seconds. - Rinse briefly with water to
remove excess methylene
blue. - Blot dry with bibulous paper.
Examine directly under oil
immersion.
Acid fast stain secondary stain
METHYLENE BLUE/
MALACHITE GREEN
Staining method for bacteria that possess ________ in their
cell walls (i.e. Mycobacterium tuberculosis and other species,
and Nocardia)
mycolic acid
is used as a decolorizer, and methylene
blue is the counterstain
Acidified alcoho
Bacteria that are not acid-fast are color what
blue
ZIEHL-NEELSEN mordant
STEAM
used to stain bacteria that have a high lipid and wax content in their cell walls and do not stain well
with traditional bacterial stains.
ACID FAST STAINING
Acid-fast bacteria retain the primary
stain and are color what
red
kinyoun METHYLENE BLUE/
MALACHITE GREEN NAF
blue