This presentation discusses paper chromatography, including its principle, types, advantages, and calculation of Rf values. Paper chromatography separates compounds based on their differential partitioning between a stationary phase (paper) and mobile phase (solvent). It has advantages like simple equipment and ability to separate closely related compounds. The distance migrated by a compound divided by the distance traveled by the solvent front gives the retention factor (Rf value), which is useful for identification. Factors like solvent composition, temperature, paper quality can influence Rf values.

1. Presentation on
Paper Chromatography
Principle and Rf Value
Presented to:-
Dr. B.M.Gurupadayya,
Dept.of Pharmaceutical Chemistry,
JSSCP, Mysore.
Presented by:-
Tekuri Manoj Kumar,
1st M.Pharm(IP).

2. Overview:-
• Introduction.
• Definition of paper chromatography.
• Principle involved in paper chromatography.
• Types of paper chromatography.
• Advantages of paper chromatography.
• Rf value.
• Factors which affect Rf value.
• References.

3. Introduction:-
• All the credit for the present status of paper
chromatography goes to Martin and his co-
workers viz. Consden, Gorden and Synge.
• Martin and Synge (1941) developed forty-
plate complicated apparatus for the
separation of acetylated amino acids.
• Consden, Gorden and Martin (1944) replaced
silica gel with a filter paper by using n-butanol
as a mobile phase.
• It was originally used to separate organic

4. Definition:-
 Paper chromatography is the
technique in which the separation of an
unknown substance is mainly carried out
by the flow of solvents on the specially
designed chromatographic paper.
 In this case the solvent goes up by
capillary action.
 The separation is effected by differential
migration of the substance due to

5. Theoretical principle:-
 largely by partition coefficient
phenomenon.
• separation is accomplished by successive
equilibrations of sample between two phases;
one of which moves over the other.
• The stationary phase is made up of the
solvent held by the paper and mobile phase
is the irrigating eluent.
• Both these phases are in contact over a very
large interface on filter paper.
• The water absorbed in amorphous regions of

7. Types of paper chromatography:-
 Depending upon the migration
forces that are involved in
separation, paper chromatography is
classified into two types.
They are:-
i. Paper partition chromatography.
ii. Paper adsorption chromatography.

8. Paper partition chromatography:-
In standard method of analysis where the
paper is utilized as a support with one solvent
as mobile phase and other as a stationary
phase. The migration of substances is due to
differences in partition coefficients.
Paper adsorption chromatography:-
In some cases the paper to be used is
coated or impregnated with adsorbents like
silica gel or aluminia, is used as an adsorbent
and the solvent is allowed to flow over the
unknown components. Thus, migration of
substances is due to the difference in
adsorptive powers of substances to be
separated.

9. Advantages over other methods:-
i. The equipment is very simple and is
easily available.
ii. It has high efficiency of separation.
iii. Separation can be effected on macro,
micro and semi-micro scale.
iv. Closely related homologues, isotopes,
isomers and very labile and reactive
substances can be separated readily and
satisfactorily.

10. Rf VALUE:-
• In paper chromatography the results are
represented by Rf value which represent
the movement or migration of solute
relative to the solvent front. This is
indicating position of migrated spots on
chromatogram.
• The Rf value is calculated as:-

11. • Rf is a function of partition coefficients and
is a constant for a given
substance, provided the conditions of
chromatographic system are kept
constant.
• For greater reliability, reference standards
are used in parallel runs or as internal
standards.
• Sometimes the solvent front runs off the
paper. Then the position of individual spot
is measured relative to position of
standard substances.
 Rf value is always less than unity but Rx

12. factors which affect Rf value are:-
• The solvent system and its
composition.
• Temperature.
• The quality of the paper.
• Distance through which the solvent
runs.
• The quality and nature of solvents
used.

13. References:-
A text book of Pharmaceutical
analysis by Dr. A.V.Kasture.
Volume – II, page no-31.

14. ….Thank