GOOD SLIDE FOR ELECTROPHORESIS

1. Presented By-
MD GHAZI MOAZZAM
M.Pharm-I sem.
BIRLA INSTITUTE OF TECHNOLOGY, MESRA-835215
GEL ELECTROPHORESIS

2.  Electrophoresis is a separation technique that is based on the
movement of charged particles in an electric field.
 The term electrophoresis was coined from a Greek word
“Phoresis” which means “Being Carried Away”.
 Hence literal meaning of the word electrophoresis means “to
carry with electricity.”

3. PRINCIPLE
• Any charged ion or molecule migrates when placed in an electric
field, the rate of migration depend upon its net charge, size, shape
and the applied electric current.
• Can be represented by following eq.
E*q
V
f
Whereby,
 v = velocity of migration of the
molecule.
 E = electric field in volts per cm
 q = net electric charge on the
molecule
 f = frictional coefficient

4. TYPES OF ELECTROPHORESIS
ELECTROPHORESIS
FREE
ELECTROPHO
RESIS
MICRO
ELECTROPHO
RESIS
MOVING
BOUNDARY
ZONE
ELECTROPHO
RESIS
PAPER
ELECTROPHO
RESIS
CELLULOSE
ACTTATE
ELECTROPHO
RESIS
GEL
OELECTROPH
RESIS

5. Introduction
Separation is brought about through molecular sieving technique, based
on the molecular size of the substances. Gel material acts as a
"molecular sieve”.
Gel is a colloid in a solid form (99% is water).
It is important that the support media is electrically neutral.
Different types of gels which can be used are; Agar and Agarose gel,
Starch, Sephadex, Polyacrylamide gels.

6. Contd..
A porous gel acts as a sieve by retarding or, in some cases, by
completely obstructing the movement of macromolecules while
allowing smaller molecules to migrate freely.
Agar gel is used for separation of different types of protein
mixtures as well as nucleic acids
Polyacrylamide is most suitable for separation of nucleic acids.
It is also frequently used in separating proteins, peptides and
amino acids from microgram quantities of mixed samples

7. Gel Electrophoresis
Agarose Gel
electrophoresis
Strach Gel
Electrophoresis
Poly acrylamide
Gel
Electrophoresis

8.  Agarose
 Polysaccharide
extracted from sea
weed.
 Gel casted horizontally
 Non-toxic.
 Separate large
molecules
 Commonly used for
DNA separations.
 Staining can be done
before or pouring the
gel.
PolyacrylamideGel
Cross-linked polymer
of acrylamide.
Gel casted vertically.
Potent neuro-toxic.
Separate small molecules.
Used for DNA or protein
separations.
Staining can be done
after pouring the gel.
Gel Types
Agarose Gel

9. Agarose gel electrophoresis
Commonly used support medium
Less expensive than cellulose acetate
Equally good separation
Agar is a complex acidic polysaccharide containing monomers of sulfated
galactose
Agarose is a sulfate free fraction of Agar
Gel is prepared in buffer and spread over a microscopic slide
A small sample of serum or biological fluid is applied by cutting in to the gel
with a sharp edge
The electrophoretic rum takes about 90 minutes
8

10. ADVANTAGES:
Easy to prepare and small concentration of agar is required.
Resolution is superior to that of filter paper.
Large quantities of proteins can be separated and recovered.
Adsorption of negatively charged protein
molecule is negligible.
It adsorbs proteins relativelyless when compared
to other medium.
Sharp zones are obtained due to less adsorption.
Recovery of protein is good, good method for
preparative purpose.
11

11. DISADVANTAGES:
Electro osmosis is high.
Resolution is less compared to polyacrylamide gels.
Differentsources and batches of agartend to give
different results and purification is often necessary.
APPLICATION:
Widely used in Immuno electrophoresis.
To separate different types of protein mixtures
as well as nucleic acids.

12. POLYACRYLAMIDE GEL ELECTROPHORESIS (PAGE)
It is prepared by polymerizing acryl amide monomers in
the presence of methylene-bis- acrylamide to cross link
the monomers.
•Structure of acrylamide (CH2=CH-CO-NH2)
•Polyacrylamide gel structure held together by covalent
cross-links.
•Polyacrylamide gels are tougher than agarose gels.
•It is thermostable, transparent, strong and relatively
chemically inert.
•Gels are uncharged and are prepared in a variety of pore
sizes.
•Proteins are separated on the basis of charge to mass
ratio and molecular size, a phenomenon c1a4 lled
Molecular sieving.

13. Types of PAGE
PAGE can be classified according the separation
conditions into:
NATIVE-PAGE:
Native gels are run in non-denaturing conditions, so that the analyte's natural
structure is maintained.
Separation is based upon charge, size, and shape of macromolecules.
Useful for separation or purification of mixture of proteins.
This was the original mode of electrophoresis.
DENATURED-PAGE OR SDS-PAGE:
Separation is based upon the molecular weight of proteins.
The common method for determining MW of proteins.
Very useful for checking purity of protein samples.

14. PAGE
PROCEDURE

15. Visualizati
onAfter the electrophoresis is complete, the molecules in the gel
can be stained to make them visible.
Ethidium bromide, silver, or coomassie blue dye may be used
for this process.
Other methods may also be used to visualize the separation of the
mixture's components on the gel.
If the analyte molecules fluoresce under ultraviolet light, a
photograph can be taken of the gel under ultraviolet lighting
conditions. If the molecules to be separated contain radioactivity
added for visibility, an autoradiogram can be recorded of the gel.

16. Differences
 SDS PAGE
• Separation is based upon
the molecular weight of
proteins.
• The most common
method for determining
MW of proteins
• Very useful for checking
purity of protein samples
Native PAGE
• Separation is based upon
charge, size, and shape
of macromolecules.
• Useful for separation
and/or purification of
mixture of proteins
• This was the original
mode of
electrophoresis.
SDS

17. ADVANTAGES:
Chemically inert.
Never bind to proteins.
Transparent to light.
Hydrophilic and electrically neutral.
Available in wide range of pore sizes.
Stable over a wide range of PH.

18. Applicatio
nsUsed for estimation of molecular weight of proteins
and nucleic acids.
Determination of subunit structure of proteins.
Purification of isolated proteins.
Monitoring changes of protein content in body
fluids.
Identifying disulfide bonds between protein
Quantifying proteins
Blotting applications

19. STARCH GEL ELECTROPHORESIS
A suspension of granular starch should be boiled in a buffer to give a clear colloidal
suspension.
The suspension on cooling sets as a semisolid gel due to intertwining of the
branched chains of amylopectin.
In order to avoid swelling and shrinking petroleum jelly is used.
ADVANTAGES:
oHigh resolving power and sharp zones are obtained.
oThe components resolved can be recovered in reasonable yield especially
proteins.
oCan be used for analytical as well as preparative electrophoresis.
DISADVANTAGES:
oElectro osmotic effect.
oVariation in pore size from batch to batch.

20. •Adamson, N. J. & Reynolds, E. C. (1997) Rules relating electrophoretic mobility, charge and molecular size of
peptides and proteins Journal of Chromatography B, Vol. 699, No. 1+2 (1997) pp.133-147, ISSN: 0378-4347.
•http://ocw.mit.edu/courses/biological-engineering/20-109-laboratory-fundamentals-in-biological-engineering-
fall-2007/labs/mod1_2/
•https://www.slideshare.net/MuhammadAsif564/electrophoresis-gel-and-cellulose-electrophoresis-
protocol?qid=f81f4a36-bd4a-4578-a26f-6b378ff0f019&v=&b=&from_search=4
•https://www.slideshare.net/harshit172/agarose-gel-electrophoresis-25523393?qid=d2084041-0d03-4a10-
836f-8913da4f1d3a&v=&b=&from_search=5
REFERENCES