A cytologic smear or cell block should be fixed using a fixative that is optimum for the type of cells, the preparation and the intended use.
Types of fixative:
(1) acetone
(2) mixture of acetone and ethanol
(3) mixture of acetone and formalin
(4) 95% ethanol
(5) formalin
(6) B5 (or a non-mercury containing substitute)
|
Type of Tissue |
Preparation |
Use |
Fixative |
|
hematopoietic |
smear |
immunoperoxidase |
acetone |
|
hematopoietic |
smear |
other |
acetone |
|
hematopoietic |
cell block |
immunoperoxidase |
B5 |
|
hematopoietic |
cell block |
other |
B5 |
|
nonhematopoietic |
smear |
immunoperoxidase |
ethanol |
|
nonhematopoietic |
smear |
other |
ethanol |
|
nonhematopoietic |
cell block |
immunoperoxidase |
ethanol |
|
nonhematopoietic |
cell block |
other |
formalin |
|
mixture |
smear |
immunoperoxidase |
acetone mixture |
|
mixture |
smear |
other |
acetone mixture |
|
mixture |
cell block |
immunoperoxidase |
ethanol |
|
mixture |
cell block |
other |
ethanol |
Smears can be fixed:
(1) Immediately, without air drying.
(2) After air drying completely for 30 minutes.
If a smear cannot be stained immediately after fixation:
(1) Completely fix the smear.
(2) Let the slide completely air dry.
(3) Wrap the slide in plastic wrap.
(4) Store in a -70°C freezer until needed.
(5) Remove from freezer and allow to warm to room temperature before removing plastic wrap.
(6) Stain.
Specialty: Clinical Laboratory
