Paraformaldehyde-Glutaldehyde Fixative (after Karnovsky, 1967)

2% PARAFORMALDEHYDE - 2.5% GLUTARALDEHYDE FIXATIVE
(after Karnovsky, 1967)

Components:

Paraformaldehyde, 8% aq.
Glutaraldehyde, 25% aq.
Cacodylate - Sucrose buffer, pH 7.4, 2X stock solution
Distilled H₂O

Formula:

	for 10 ml	for 50 ml
8% paraformaldehyde	2.5 ml	12.5 ml
25% glutaraldehyde	1.0	5.0
0.2 M cacodylate - 0.2 M sucrose	5.0	25.0
distilled H₂O	1.5	7.5

Method:

Mix first three ingredients.
Adjust pH to 7.4 with NaOH.
Bring to final volume with distilled H₂O.
Use immediately.

CAUTION: First three components are toxic. Contains arsenic. Use fume hood. Exercise caution in handling. DO NOT PIPET BY MOUTH.