Routine Fixatives Flashcards
1
Q
Gas by weight of commercial formaldehyde
A
35-40%
2
Q
10mL formalin, 90mL saline; most widely used fixative
A
10% formol-saline/formalin
3
Q
pH of formalin
A
7.0
4
Q
Phosphate buffer
A
Calcium acetate buffer
5
Q
Inhibit formation of paraformaldehyde (white ppt)
A
10% methanol
6
Q
What to do when white ppt forms
A
Filtration
7
Q
Best fixative for nervous tissue
A
Formalin
8
Q
Brownish black crystalline ppt; doubly recractile; consist of acid formaldehyde
A
Hematin
9
Q
Remedy to fat dispersal
A
Cobalt/Cadmium salts
10
Q
Prevent pigmentation
A
Calcium/Magnesium carbonate added to 10-15% formalin
11
Q
Placing formaldehyde fixed specimens in acetone, 28% ammonia water, H202; uses 70 % alcohol as ronsing agent
A
Lillie’s method
12
Q
Formaldehyde clearance involving 70% rthanol and 28% ammonia water
A
Kardasewitch’s method
