INTRODUCTION HISTORY PRINCIPLE What is SDS PAGE ? PROCEDURE sample preparation preparing acrylamide gels electrophoresis APPLICATION OF SDS PAGE CONCLUSION REFERENCE

1. By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. SYNOPSIS
 INTRODUCTION
 HISTORY
 PRINCIPLE
 What is SDS PAGE ?
 PROCEDURE
 sample preparation
 preparing acrylamide gels
 electrophoresis
 APPLICATION OF SDS PAGE
 CONCLUSION
 REFERENCE

3. INTRODUCTION
The separation of macromolecules in an electric field is called electrophoresis.
A very common method for separating proteins by electrophoresis uses a
discontinuous polyacrylamide gel as a support medium and sodium dodecyl sulfate
(SDS) to denature the proteins.
The method is called sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-
PAGE).
HISTORY
The most commonly used system is also called the Laemmli method after U.K.
Laemmli,
who was the first to publish a paper employing SDS-PAGE in a scientific study.

4. PRINCIPLE
• Electrophoresis is the study of the movement of the
charge molecules in an electric field.
• Two medium generally used-
• 1.cellulose
• 2.polyacrylamide gel or agarose
• SDS disrupts the secondary,tertiary,& quaternary
stru.of the protein to produce a linear poly peptide chain
coated with negatively charged SDS molecules

5. WHAT IS SDS PAGE ?
• The purpose of SDS-PAGE is to separate proteins according to their
size.
• We have two word 1.SDS, 2.PAGE
• SDS
• SDS {sodium dodecyl sulfate} is a detergent or soap that
can dissolve hydrophobic molecules but also has a negative charge
attached to it.
•

6. PAGE
• If the proteins are denatured and put into an electric
field, they will all move towards the positive pole at the
same rate, with no separation by size.
• So we need to put the proteins into an environment that
will allow different sized proteins to move at different
rates.
• The environment of choice is polyacrylamide, which is a
polymer of acrylamide monomers.
• When this polymer is formed, it turns into a gel and we
will use electricity to pull the proteins through the gel
• so the entire process is called polyacrylamide gel
electrophoresis.

7. Now ready to apply the mixture of denatured
proteins to the gel and apply the current.
Small molecule size run faster than large
molecule.
Since all the protein have strong negative
charge they will all move in the direction arrow
is pointing.

8. The gel has five number lanes where five different samples of proteins were
applied to the gel.
Lane 1, molecular weight standards of known sizes;
Lane 2, a mixture of three proteins of different sizes with a being the largest
and c being the smallest protein;
Lane 3, protein a by itself;
Lane 4, protein b by itself;
Lane 5 protein c by itself.

9. Procedure
1.sample preparation

10. Preparing acrylamide gels

11. ELECTROPHORESIS
Various buffer systems are used in PAGE depending on the nature of the
sample and the experimental objective. The buffers used at the anode and
cathode may be the same or different.

12. APPLICATION OF SDS-PAGE
• This technique mostly used in, forensic
genetics, biochemistry,molecular biology
and biotechnology to separate biological
macromolecules, usually proteins or nucleic
acids, according to their electrophoretic
mobility.
• Mobility is a function of the length,
conformation and charge of the molecule

13. Conclusion
• We can separate various type of protein
on the basis of molecular weight .
• we use SDS to denature all protein to the
same linear shape & Page separate it on
the basis of different size of protein.
• This support medium is more sufficient
than other medium such as cellulose
medium.

14. Reference
• AN INTRODUCTION OF PRACTICAL
BIOCHEMISTRY 3RD EDITION 2006.
• WIKIPIDIA.COM