3. INTRODUCTION
• Centrifugation is a process which involves the
use of the centrifugal force for the
sedimentation of heterogeneous mixtures with
a centrifuge, used in industry and laboratory
settings.
• This process is used to separate two
immiscible liquids.
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5. DEFINITION
• A centrifugation is a
technique for
separating particles
from a solution
according to their
size, shape, density,
viscosity of the
medium and rotor
speed.
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6. CENTRIFUGE
• A centrifuge is a part
of equipment that puts
an object in rotation
around a fixed axis
(spin in a circle),
applying a potentially
strong force
perpendicular to the
axis of spin.
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7. PRINCIPLE
• In a solution, particles whose density is higher than
that of the solvent sink (sediment), and particles that
are lighter than it float to the top.
• The greater the difference in density, the faster they
move. If there is no difference in density (isopycnic
conditions), the particles stay steady.
• To take advantage of even tiny differences in density
to separate various particles in a solution, gravity can
be replaced with the much more powerful
“centrifugal force” provided by a centrifuge.
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8. COMPONENTS OF CENTRIFUGE
• Motor- which give rotator motion.
• Drive shaft- attached to motor.
• Rotor- placed on drive shaft having space to
place tubes.
• Centrifuge rotor: a rotor is the rotating unit of
the centrifuge, which has fixed holes drilled at
an angle. Test tubes are placed inside these
holes and the rotor spins to aid in the
separation of the materials.
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12. TYPES OF CENTRIFUGATION
Preparative centrifugation:
• it is a preliminary step to separate component for
further separation and analysis. It can handle large
amount of samples. Its divide 2 types:
• Density gradient centrifugation
• Differential velocity centrifugation
Analytical centrifugation:
• we analyze the sample so small amount is used
few micro-gram/ L to 1 mL
• Mostly ultracentrifuge is used
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13. DENSITY GRADIENT CENTRIFUGATION
• Under centrifugal force, the particles will
begin sedimenting through the density
gradient.
• Two type of this-
1. Rate zonal centrifugation
2. Isopycnic centrifugation
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20. ULTRACENTRIFUGATION
• The ultracentrifuge is a centrifuge optimized
for spinning a rotor at very high speeds,
capable of generating acceleration as high as
19600 km/s² (around 50000 rpm).
• Example: Red cells may be separated from
plasma of blood, nuclei from mitochondria in
cell homogenates, and one protein from
another in complex mixtures.
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29. CONCLUSION
• The centrifugation is a modern and easy
technique of separation.
• Due to centrifugation it is easy to separate
cellular and sub cellular components.
• It is used to study the effects of centrifugal
forces on cells.
• But it is costly and problem to maintenance.
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