Compound fixative - association

fast-acting

Formal Acetic Acid

diagnostic cryostat sections.

Formal Acetic Acid

Morphologic preservation by ___ is probably the most life-like.

formaldehyde

Leaves tissue soft

picric acid

Swells collagen (protein) and lyse red blood cells

acetic acid

dual-purpose fixative.

FA-GA

keeps the specimen suitable for EM after prolonged storage.

FA-GA

Stable for at least 3 months if stored at 4C.

FA-GA

hematopoietic and lymphoreticular tissue

B-5 Solution

bone marrow and lymphomas

B-5 Solution

mercuric chloride, sodium acetate, and FA.

B-5 Solution

sodium acetate

B-5 Solution

differentiate blood cell types, visualize parasites, and analyze bone marrow.

Wright stain

leukemia, infections, and identifying eosinophils.

Wright stain

Excellent for biopsy specimens of the gastrointestinal

Bouin Solution

Useful for preserving glycogen, animal embryos, endocrine gland tissue, and many antibodies react well

Bouin Solution

preserving structure with soft and delicate textures.

Bouin Solution

fat fixative, especially lymph nodes, fatty breast tissue, and lipomas.

Bouin Solution

tissue will easily section with this fixative.

Bouin Solution

gastrointestinal tract, fatty breast tissue, lipomas, animal embryos, endocrine gland tissue

Bouin solution

dissolves iron and small calcium deposits

Bouin Solution

must be washed from the tissue prior to staining with 50% - 70% alcohol or 70% alcohol saturated with lithium carbonate.

Bouin Solution

If excess picric acid is left in embedded tissues, the staining will deteriorate over time.

Bouin Solution

The retina of the eye also does not tend to detach as it does with formalin fixation.

Davidson Solution

Smaller samples, gynecologic specimens, fatty breast specimens, lymph nodes, and bone marrow have good nuclear staining

Davidson Solution

improves upon aging.

Gendre Solution

Alcoholic Bouin solution

Gendre Solution

95% alcohol with picric acid and glacial acetic acid.

Gendre Solution

glycogen and carbohydrate

Gendre Solution

It's one of the oldest fixatives.

Clarke Solution

It’s a rapid fixative and a 1 – 2 mm piece of tissue will usually be fixed within an hour or two

Clarke Solution

Carnoy without chloroform

Clarke Solution

frozen sections, blood and chromosome smears.

Clarke Solution

absolute ethanol and glacial acetic acid.

Clarke Solution

Carnoy has ___, Clarke does not

chloroform

gastrointestinal tract and prostate biopsies.

Hollande Solution

contains copper acetate which stabilizes red blood cell membranes and the granules of eosinophils and endocrine cells

Hollande Solution

To prepare the solution, dissolve copper acetate in water without heat, add picric acid slowly, stir until dissolved.

Hollande Solution

copper acetate, picric acid, 40% FA, and acetic acid.

Hollande Solution

Small bone specimens, GI tract, prostate biopsies

Hollande solution

Mercuric chloride fixatives include Zenker’s fixative, which adds ___, and Helly’s fixative, which adds ___.

acetic acid, formaldehyde

___ has largely come to replace mercury as its use in fixatives gives great nuclear detail and no antigen retrieval is necessary in IHC.

Zinc sulfate

___ is stable and may be prepared in large quantities.

Zenker

Solutions that use acetic acid (7)

Davidson, Zenker, Bouin, Hollande, Gendre, Carnoy, Clarke

It can fix and decalcify needle biopsy specimens of bone marrow but will dissolve iron.

Zenker

animal or vegetable prep for microscopic study.

Zenker

exceptionally bloody specimens such as infarcts and congested spleens.

Zenker

for unusual tumors, such as rhabdomyosarcoma and malignant teratomas.

Zenker

preservation of tissue which Feulgen plasma reaction.

Zenker

It is excellent for trichrome staining, PTAH muscle staining, unusual tumors, and viral inclusions such as Negri bodies.

Zenker

Never use metallic forceps or metal containers when handling any tissue fixed in mercurial fixatives.

Zenker, Helly, B-5

mercuric chloride, potassium dichromate, sodium sulfate, and glacial acetic acid.

Zenker

Mercury and chrome pigments may form

Zenker, Helly

intercalated discs of cardiac muscles, bone marrow

Helly

The FA must be added immediately before use, or the solution will darken and have a precipitate upon standing.

Helly

FA causes reduction of some chemicals in the solutions and is not stable.

Helly

mercuric chloride, potassium dichromate, sodium sulfate, and FA.

Helly

demonstrate chromaffin granules in the cytoplasm of the adrenal medulla (pheochromocytoma).

Orth

It is not a good general purpose fixative.

Orth

The reaction is most intense at a pH of 5 – 6.

Orth

The chromaffin granules are colored orange to brown by chromate.

Orth

potassium dichromate, sodium sulfate, and FA.

Orth

Modification of Bouin solution; PFA instead of formalin and additional buffering with phosphate and caustic soda.

Zamboni

Instead of the very acidic Bouin solution, a fixative with a pH value in the range of 7 results

Zamboni

Allows specimens to be kept at room temperature indefinitely and be sent through the mail.

Zamboni

Allows secondary fixation with osmium because it is easy to use and preserve morphology.

Zamboni

PFA, picric acid, and sodium hydroxide.

Zamboni

Modified Bouin solutions (3)

Gendre, Hollande, Zamboni

Alternatives to mercuric chloride formulations, is compatible with histochemical, immunochemical and special stains.

Zinc Formalin

4 to 6 hours for biopsy tissue and 6 to 8 hours for most other tissue.

Zinc Formalin

Nissl granules

Carnoy

RNA stains

Carnoy

Besides acetic acid, it is another preferred fixative for nucleic acids.

Carnoy

sometimes used in cytology because it lyses RBCs

Carnoy

It is also a very fast fixative (put in the fridge to slow down fixation time)

Carnoy

surgical removal of keratocysts; type of chemical cauterization

Carnoy

not good to stain acid-fast bacilli (AFB) \

Carnoy

dissolves acid soluble cell granules and pigments

Carnoy

absolute ethanol, chloroform, and glacial acetic acid with the fixation time between 1 and 4 hours.

Carnoy

Substitutes methyl alcohol for the ethyl alcohol in Carnoy solution and it hardens and shrinks tissue less than Carnoy.

Methacarn solution

absolute methanol, chloroform, and glacial acetic alcohol with a fixation time of 1 to 4 hours.

Methacarn solution

Used to transport specimens such as renal biopsies and lymph nodes for IF studies but not muscle biopsies.

Michel Transport Medium

citric acid, ammonium sulfate, N-ethylmaleimide, and magnesium sulfate and must maintain a pH of 7.0 -7.2.

Michel Transport Medium