FIXATIVES

Jenivie Morillo JoseUniversity of Santo Tomas

National Children’s Hospital

FIXATIVES

SIMPLE COMPOUND

Metallic

Picric Acid

Aldehyde

Acetic Acid

Acetone

Alcohol

Osmium Tetraoxide

Micro-Anatomical

Cytological

SIMPLE FIXATIVES

I.ALDEHYDE FIXATIVES

-for ROUTINE PARAFFIN SECTIONS, FROZEN SECTIONS, ELECTRON MICROSCOPY

SIMPLE FIXATIVES

A.FORMALDEHYDE

-produced by the OXIDATION of METHYL ALCOHOL

-soluble in WATER to extent of 40% by weight

-powerful REDUCING AGENT

FIXATION TIME: 12-24 hrs.

SIMPLE FIXATIVES

ADVANTAGES: CHEAP, readily available, easy to

prepare, relatively stable PENETRATE tissue well Doesn’t OVERHARDEN tissues Preserves FAT and MUCIN BEST FIXATIVE for NERVOUS TISSUE

SIMPLE FIXATIVES

DISADVANTAGES: Causes ALLERGIC DERMATITIS,

ALLERGIC RHINITIS and SINUSITIS SHRINKAGE of tissues REDUCES BASOPHILIC, EOSINOPHILIC

staining of cells Forms abundant BROWN ARTIFACTS,

PIGMENTS and GRANULES

SIMPLE FIXATIVES

REMOVAL OF FORMALIN PIGMENTS:

KARDASEWITSCH’S METHOD

LILIE’S METHOD

PICRIC ACID METHOD

SIMPLE FIXATIVES

B. GLUTARALDEHYDE

-aldehyde M.W. 100

-2 FORMALDEHYDE residues linked by straight 3 CARBON CHAINS

SIMPLE FIXATIVES

ADVANTAGES:

Stable nature, effect on tissues, giving firmer texture and color

Preserves CELLULAR and PLASMA PROTEIN better

SIMPLE FIXATIVES

DISADVANTAGES:

MORE expensive

LESS stable

SIMPLE FIXATIVES

C.PARAFORMALDEHYDE

-polymer of formaldehyde

-white powder

SIMPLE FIXATIVES

ADVANTAGES:

EXCELLENT FIXATIVE for ROUTINE PARAFFIN SECTIONS

For THIN and ULTRATHIN sections for PLASTIC EMBEDDING

SIMPLE FIXATIVES

DISADVANTAGES:

Expensive

UNSTABLE

SIMPLE FIXATIVES

II. METALLIC FIXATIVES

SIMPLE FIXATIVES

A.MERCURIC CHLORIDE

-frequently used in SATURATED SOLUTION

SIMPLE FIXATIVES

ADVANTAGES:

PENETRATES and HARDENS tissue rapidly

Gives BETTER STAINING of NUCLEI and CONNECTIVE TISSUE

recommended for RENAL, FIBRIN and CONNECTIVE TISSUE

SIMPLE FIXATIVES

DISADVANTAGES:

SHRINKAGE of cells LESS stable Corrodes metals except NICKEL

SIMPLE FIXATIVES

B.CHROMATE FIXATIVES

-STRONG OXIDIZING AGENT -shouldn’t combine with REDUCING

AGENTS like ALCOHOL and FORMALIN

SIMPLE FIXATIVES

ADVANTAGES:

Strong PROTEIN PRECIPITANT

Preserves CARBOHYDRATES

SIMPLE FIXATIVES

DISADVANTAGES:

Forms a PRECIPITATE of INSOLUBLE suboxide

POOR for GLYCOGEN FIXATION

SIMPLE FIXATIVES

Potassium Dichromate -STRONG FIXATIVE for LIPIDS

ADVANTAGES: Fixes but DOES NOT PRECIPITATE CYTOPLASMIC

CONTENTS Preserves MITOCHONDRIA

DISADVANTAGE:

Penetrates tissue SLOWLY

SIMPLE FIXATIVES

C.LEAD FIXATIVES

-ADVANTAGES:

mainly for MUCOPOLYSACCHARIDES

precipitates PROTEIN

SIMPLE FIXATIVES

DISADVANTAGES:

Penetrates tissue SLOWLY

Expensive

SIMPLE FIXATIVES

III. PICRIC ACID FIXATIVES

STRONG or SATURATED SOLUTION

-2,4,6-trinitrophenol

SIMPLE FIXATIVES

ADVANTAGES:

Best fixative for GLYCOGEN

Penetrates tissue RAPIDLY

SIMPLE FIXATIVES

DISADVANTAGES:

LYSES red blood cells

SHRINKAGE of tissues

SIMPLE FIXATIVES

IV. ACETIC ACID FIXATIVEADVANTAGES:

Fixes and precipitates NUCLEOPROTEIN

Precipitates CHROMOSOMES, CHROMATIN MATERIALS

SIMPLE FIXATIVES

DISADVANTAGES:

SWELLING of tissues

DESTROYS MITOCHONDRIA and GOLGI ELEMENTS

SIMPLE FIXATIVES

V. ACETONE

-used only in ENZYME STUDIES

SIMPLE FIXATIVES

ADVANTAGES:

Recommended for PHOSPHATASES and LIPASES studies

For fixing BRAIN TISSUES for RABIES

SIMPLE FIXATIVES

DISADVANTAGES:

EVAPORATES rapidly

DISSOLVES fats

SIMPLE FIXATIVES

VI. ALCOHOL FIXATIVES

for RAPID DENATURING and PRECIPITATION of PROTEINS by destroying HYDROGEN and other BOND

SIMPLE FIXATIVES

ADVANTAGES:

IDEAL for SMALLER tissue FRAGMENTS

EXCELLENT for GLYCOGEN preservation

SIMPLE FIXATIVES

DISADVANTAGES:

LYSES red blood cells

DISSOLVES LIPIDS and FATS

POLARIZATION of GLYCOGEN

SIMPLE FIXATIVES

VII. OSMIUM TETROXIDE FIXATIVES

-osmic acid

-pale yellow

-dissolves in water

-STRONG OXIDIZING AGENT

SIMPLE FIXATIVES

ADVANTAGES:

Fixes CONJUGATE FATS and LIPIDS permanently

EXCELLENT NUCLEAR staining

SIMPLE FIXATIVES

DISADVANTAGES:

VERY expensive

SLOW fixing agent

COMPOUND FIXATIVES

I. MICRO-ANATOMICAL FIXATIVES

COMPOUND FIXATIVES

10 % FORMOL SALINE -for NERVOUS system and GENERAL

post mortem materials

10% BUFFERED FORMALIN -for post mortem SURGICAL

RESEARCH

COMPOUND FIXATIVES

HEIDENHAIN’S SUSA SOLUTION -for biopsies of the SKIN

FORMOL SUBLIMATE -for ROUTINE post mortem materials

COMPOUND FIXATIVES

FORMOL SALINE SUBLIMATE -for post mortem materials

ZENKER’S SOLUTION -for post mortem materials

COMPOUND FIXATIVES

ZENKER’S FORMOL (HELLY’S FLUID) -for PITUITARY TISSUES and BONES

BOUIN’S SOLUTION -for EMBROYS

COMPOUND FIXATIVES

II. CYTOLOGICAL FIXATIVE

A. NUCLEAR FIXATIVE

COMPOUND FIXATIVES

FLEMMING’S FLUID -for nuclear structures

CARNOY’S FLUID -for CHROMOSOMES STUDY, LYMPH

NODES, GLYCOGEN

COMPOUND FIXATIVES

BOUIN’S FLUID -for EMBRYOS and GLYCOGEN

NEWCOMER’S FLUID -for MUCOPOLYSACCHARIDES,

NUCLEAR PROTEIN and CHROMOSOMES

COMPOUND FIXATIVES

B. CYTOPLASMIC FIXATIVE

FLEMMING’S FLUID(minus ACETIC ACID)

-for CYTOPLASMIC STRUCTURES

CHAMPY’S FLUID -for MITOCHONDRIA, GOLGI

ELEMENTS and FATS

COMPOUND FIXATIVES

REGAUD’S FLUID(MOLLER) - for MITOCHONDRIA and YOLK

ORTH’S FLUID -for EARLY DEGENERATIVE PROCESS

and TISSUE NECROSIS

Thank you