Road to RMT: Fixative Solution

Formaldehyde

Most commonly used fixatives and it is a tolerant fixative

Every 3 months

Bleaching may be prevented by changing the solution every?

10% NBF

For preservation and storage of Surgical, Post Martem research specimens

10% NBF

Best fixative for iron containing tissues

10% NBF

Posivity of Mucin to Periodic Acid Schiff is reduced

Gendre’s Fluid

Good preservation of glycogen and for microincineration technique

Gendre’s Fluid

Used to fix sputum, since it coagulates mucus

10% Formol Saline

For fixation of CNS tissue and general posy-martem tissues

10% Formol Saline

Ideal for most staining technique, including silver impregnation

10% Formol Saline

It preserves enzyme and demonstrates fats and mucin

Formol Corrosive

No need for washing out

Formol Corrosive

Recommended for routine postmortem tissues

Zinc Formalin

Alternative for mercuric chloride formulations

Paraformaldehyde

It is usually obtained as a fine white powder which depolymerizes back to formalin when heated

Karnovsky’s Fixative

For light microscopy, resin embedding and sectioning and for electron microscopy

Glutataldehyde

It is made up of 2 formaldehyde residues that is linked by a three carbon chain

Lead Oxaloacetate

It is a primary reaction product precipitate for the visualization of the activity of glutamic oxaloacetic transminase in the tissue sections

Lead Fixatives

Recommended for Acid Mucopolysaccharides

Chromate Fixatives

It is highly corrosive to the skin and mucous membranes

Chromic Acid

1 to 2% aqeous solution, usually as a constituent of compound fixatives

Chromic Acid

Precipitates all proteins and adequately preserves carbohydrates

Potassium Dichromate

Preserved mitochondria

Regaud’s Muller’s

Recommended for demonstration of chromatin, mitochondria, mitotic figures and carbohydrates

Orth’s

It demonstrate ricketssis and other bacteria

Orth’s

It is the study of early degenerative processes and tissue necrosis

Mercuric Chloride Fixatives

It is recommended for renal tissues, fibrin, connective tissue and muscles

Mercuric Chloride Fixatives

It causes mark shrinkage of cells and formation of black granular deposits

Mercuric Chloride Fixative

The most common metallic fixative frequently used at a concentration of 5 to 7%

Zenker’s Fluid

It may act as a mordant for certain special staining reactions

Zenker’s Fluid

It is for fixing small pieces of liver, spleen, CT fibers and nuclei

Zenker’s Formol

It is an excellent microanatomic fixative for pituitary gland, bone marrow and blood containing organs

Heidenhain’s SuSa

It is recommended mainly for tumor biopsies of the skin

Heidenhain’s SuSa

It produce minimum shrinkage and hardening of tissues

B-5 Fixative

Used for cytology of bone marrow biopsies

100% Methanol

Excellent fixative for dry and wet smears, blood smears and bone marrow tissues

95% Ethanol

Use for exfoliative cytology

95% ethanol

It gives the most usable DNA fragments for PCR

95% Isopropanol

Used for fixing touch preparations

Carnoy’s

The most rapid fixative

Carnoy’s

Used to fix brain tissue for diagnosis of rabies

Newcomer’s

It is both a nuclear and histochemical fixative

Newcomer’s

Recommended for fixing mucopolysaccharides and nuclear proteins

Clarke’s

Recommended for frozen sections and smears

Bouin’s Fluid

For fixation of embryo’s and pituitary biopsies

Bouin’s Fluid

Preferred for tissues to be stained by Masson’s Trichome stain

Masson’s Trichrome stain

It is a stained preferre to be stained by?

Bouin’s Fluid

Not suitable for fixing kidney structures, lilid and mucus

Brasil’s Alcoholic Picroformol

It is best for glycogen demonstration

Brasil’s Alcoholic picroformol

It is better and less messy than Bouin’s fixative

Flemming’s soluition

Most common chrome-osmium acetic acid fixative

Flemming’s solution

It is recommended for nuclear preparation and permanently fixes fats

Flemming’s w/o HAc

It is recommended for cytoplasmic structures and permanently fixes fats

Acetone

Not recommended as a morphological fixative

Acetone

It acts both as a fixative and dehydrating agent

Glacial Acetic Acid

It solidifies at ____________

Glacial Acetic Acid

The most compound nuclear fixatives

Trichloroacetic Acid

The week decalcifying agent

Heat Fixation

Simplest form of fixation

Microwave Fixation

It works as a physical agent similar in mechanism to vacuum, oven and agitation to increase the movement of molecules and accelarate fixation

Microwave Stabilization

No chemical fixative is used at this stage

Microwave- assisted fixation

Carried out while tissues is in fixative

Microwave assisted fixation

It is used to assist the action of the fixing agent

Post Chromatization

It is form of secondary fixation whereby a primarily fixed tissue is placed in a 2.5 to 3% potassium dichromate solution for 24 hours

Lilie’s Method

Acetone + 28% ammonia

Tap Water

Remove excess chromates in tissues fixed in Helly’s, Zenker’s and Flemming’s fluid

50-70% Alcohol

Removes excess picric acid

Alcohol iodine

Removes excess mercurial fixatives

Kardasewitsch’s method

Ethanol + 28% ammonia

Heat fixation and microwave fixation

2 Physical Methods of Fixation