Transcript Acid

Practical seminar 4
• Acid fast staining - Mycobacterium
tuberculosis
• Corynebacteriuôm diphtheriae – Albert´s
staining of metachromatic granules
Acid fast staining
• Bacterial cell resistant to colorisation with some staining
(Gram)
• Their cell wall is relatively not permeable, containig lipids,
fatty acids...(ex. Mycobacterium tbc, Corynebacteria...)
• If stained (with strong basic stains (basic fuchsin in 5%
fenole –
they resist to decolorisation
with strong acids
(20% H2SO4)
Ziehl Neelsen staining
• Heat fixed smear
• Apply carbol fuchsin
(basic fuchsin + phenol)
• Warm untill evaporation
• Rinse with water
• Apply 3% HCl (or 95% alcohol
• Counterstain with malachit green
Mycobacterium tbc – farbenie podľa Ziehl Neelsena
Metachromatic granules staining
•
•
•
•
•
Volutin storage granules in cytoplasma
Stained with basic stain
Toluidin blue, methylen blue
They are acidoresistent
Differentiation of C. difteriae from
saprophytic corynebacteria
• Albert´s staining
Metachromatic staining principals
• Stain aplied on fixed cell or tissue is of
different color as is the result color
• Ernst Babes inclusions – metachromatic
granuls – volutine granuls – phosphate
molecules - Corynebacterium diphteriae
• Volutin – nucleoprotein complex – in
cytoplasm of some bacteria, molds and
parasits in the forme of storage granules
Albert´s staining
•
•
•
•
Fix smear
Apply Albert´s solution
Add Lugol solution
Bacteria are green or blue, (malachit green
or methylen blue), granuls are red