1. Pharmaceutical Engineering
S. Y. B.Pharmacy (Semester-3)
(Strictly Based as per PCI )
Presented by;-
Tejas Mahendra Bhatia
(Second Year Student)
Appasaheb Birnale College Of Pharmacy,
Sangli
Centrifugation
3. Centrifugation is the process in which
centrifugal force is used as a driving force for
phase separation.
Separation between the liquid & solid phases
are on basis of particle size and density
difference.
The equipment used for centrifugation is known
as centrifuge.
Centrifuges are used for separation of
macromolecules (Proteins & nucleic acid),
separation of two immiscible liquids, separation
of living components such as cells, viruses, sub-
cellular organelles.
Centrifugation is widely employed when
filtration process is not applicable
4. Sedimentation(Particles sediment after
separation)
This sedimentation of particles, including cells, can
be explained by the Stokes equation, which
describes the movement of a sphere in a
gravitational field.
V = Sedimentation rate or velocity of settling the
sphere
d = Diameter of the sphere
p = Particle density
Po = Medium density
n = Viscosity of medium
5. Centrifugation is one of the most important and
widely applied research techniques in biochemistry,
cellular and molecular biology and in evaluation of
suspensions and emulsions in pharmacy and
medicine.
Centrifugation, clearly, plays an important role in the
pharmaceutical industry in the production of bulk
drugs, biological products, and determination of
molecular weight of colloids and in the evaluation of
Importance of Centrifugation in
Pharmaceutical Industry….?
6.
7. Selected definitions;-
Centrifugation:- It is process in which
centrifugal force is used as driving force
for phase separation.
Centrifuge:- The equipment used for
centrifugation is called centrifuge.
Centrifugal Effect (C) or Relative Centrifugal
Force:- It is ratio of centrifugal force (F) and
gravitational Force (G)
9. Objectives…..?
Centrifugation is a technique of separating
substances which involves the application of
centrifugal force.
The particles are separated from a solution
according to their size, shape, density, viscosity
of the medium and rotor speed.
Separation is achieved by spinning a vessel
containing material at high speed; the centrifugal
force pushes heavier materials to the outside of
the vessel.
A centrifuge is a laboratory device used for the
separation of immiscible fluids, gas or liquid.
10. Principle…..?
Centrifugation is used to separate all types of particle
based upon their sedimentation properties. The
sedimentation properties of particles depend on a
number of different factors including size, density and
shape. However, both density and shape vary
significantly depending on the composition of the
solution in which the particles are suspended.
Particles are separated primarily on the basis of
either their density (isopycnic separations) or size
(differential pelleting and rate-zonal separations). The
density affect sedimentation to a much lesser extent
than size.
In centrifugation it is important to differentiate
11. Centrifuge involves principle of sedimentation
where acceleration at centripetal force causes
denser substances, to separate along radial
direction at bottom of tube, and lighter objects will
tend up the tube.
Particles having size more than 5um are
separated by simple filtration method, while
particles having size 5um or less do not sediment
under gravity. Centrifugal Force is used to
separate them.
12.
13.
14.
15. High centrifugal force is required if the particles in
suspensions are very small. To separate such small
particles from suspensions the centrifuge is designed to
be small in size that can operate at very high speed of
rotation.
If a large amount of material is to be separated and a
low centrifugal effect is sufficient to separate the
suspension then the diameter of the centrifuge is
Application of This Principle
16. Applications….
Production of bulk drugs:- Centrifugation
technique is used to separate crystalline drugs like
aspirin from mother liquor.
Production of biological products:- Most of
proteinaceous drugs and macromolecules are
present as colloidal dispersion in water.
Centrifugation is used to separate them. Insulin can
be obtained by process of ultracentrifugation.
Biopharmaceutical Analysis of drugs:-Drugs
present in blood tissue fluid and urine are normally
present in form of colloidal dispersion.
Centrifugation is used for separation of drugs and
calculating pharmacokinetic calculations.
17. Evaluation of suspensions and
emulsions:- Centrifugation process is
carried out for evaluation by rapid
empirical test parameters. A stable
emulsion should not show any signs of
separation even after centrifugating at
2000-3000 RPM at room temperature.
Determination of Molecular Weight of
colloids:- Determination of molecular
weight of polymer is not possible by
general methods. Centrifugation
methods are used for determination of
serum albumin, insulin & methyl
cellulose.