1. Dr. P. Suganya
Assistant Professor
Department Of Biotechnology
Sri Kaliswari College, (Autonomous)
Sivakasi
SUB CELLULAR
FRACTIONATION
2. Cell fractionation is the process used to
separate cellular components while preserving individual functions
of each component.
This is a method that was originally used to demonstrate
the cellular location of various biochemical processes.
7. Centriguge ia an apparatus- used to –separate
particles –suspended in a solution- by
centrifugal force
Its works on – principle- centrifugation-
operates- molecules based on their size &
mass
Centrifugation-Is a process- separation of
particles- suspended in a solution- by
centrifugal force
CENTRIFUGE
8. The process of centrifugation relies on
the perpendicular force created when a
sample is rotated about a fixed point.
The rate of centrifugation is dependent
on the size and density of the particles
present in the solution.
DEFINITION
11. The spinning produces a force called centrifugal force
The centrifugal force causes the substances to move
away from the axis more rapidly
The movement of particles is called sedimentation.
The particles settle because of gravity.
The rate of movement of particles is called
sedimentation rate.
The sedimentation rate depends on the size& density
of the particles. The larger and denser particles settle
first. This is followed by smaller and less denser
particles.
PRINCIPLE
12. The sedimented particle is called pellet. The solution
above the pellet is called supernatant.
The particles settle down because of gravitational
pull. The spinning increase the gravitational pull.
The speed of centrifuge is expressed as rpm
(resolutions per minutes or seconds)
The greater the rpm, the greater will be the
centrifugal force.
The longer the radius of rotation, the greater will be
the centrifugal force.
13. The rate of sedimentation depends on
1. The density of the particles
2. The size of the particles
3. The viscosity of the medium
4. The gravitational pull
The gravitational field is generally denoted as RCF (Relative Centrifugal
force) expressed in g units. The RCF depends on-
1. Number of revolutions per minute- rpm2
2. Radius of rotation-r
3. Gravitational Pull-g
RCF (g Force)= 1.118 × 10-5 × r × (RPM)2
where r is the radius of the rotor (in centimeters), and RPM is the speed of the
rotor in rotation per minute.
14.
15. o Centrifuge is an apparatus used to separate particles by
centrifugal force
o The centrifuge consist of a motor and rotor. The motor makes
the rotor to spin
o The motor is fitted with horizontal rod or a disc containing
holders for placing the tubes
o The entire set up is kept in a container
o The rotors are of two types namely angle type and swinging
bucket type.
o In angle type, the holders and sample tubes swing up and run
horizontally while spinning
STRUCTURE OF
CENTRIFUGE
20. o 1. Benchtop centrifuge
o 2. Continuous flow centrifuge
o 3. Gas centrifuge
o 4. Hematocrit centrifuge
o 5. High-speed centrifuge
o 6. Low-speed centrifuge
o 7. Microcentrifuge
o 8. Refrigerated centrifuges
o 9. Ultracentrifuges
o 10. Vacuum centrifuge/ Concentrators
TYPES OF CENTRIFUGE
