Centrifugation Faculty

Zaki Farhad HabibLecturer, Department of

Pharmaceutical Sciences, NSU

Group members

Md Samrul IslamSabbir Ahmed

Mimma Sultana ChandniReeti Sushan Roy

Faria Iqbal Mosharaf Hossain

Definition Principle of Centrifugation Classification of Centrifugation CONSTRUCTION ADVANTAGES AND DISADVANTAGES Application in industry Application in Water Treatment References

Contents

Centrifugation is a process used to separate or concentrate materials suspended in a liquid medium. The theoretical basis of this technique is the effect of gravity on particles (including macromolecules) in suspension. Two particles of different masses will settle in a tube at different rates in response to gravity. 

Centrifugation

A particle,whether it is precipitate,a macromolucle or cell organelle when rotated at high speed is subjected to a centrifugal force. Centrifugal force is defined as F=mw2r Where F=intensity of centrifugal force m= effective mass of sedimenting particle w= angular velocity of rotation r = distance of migrating particles from central axis of rotation

CENTRIFUGATION:

Principle of Centrifugation

Principles of Centrifuges

Basis of Separation : Size Shape Density

Methodology:

Utilizes density difference between the particles and the medium in which these are dispersed

Dispersed systems are subjected to artificially induced gravitational fields.

The centrifugal force causes the sedimentation of heavier solid particles.

Centrifugal Force :Consider a body of mass m rotating in a circular path of radius r at a velocity v. The force acting on the body in a radial direction is given by:

F =

Here, F = centrifugal force m = mass of the body v = velocity of body r = radius of circle of rotation

mv 2r

The same body will be acted upon by a gravitational force. It can be expressed as: G = mgwhere, G = gravitational force , and g = gravitational constant

The centrifugal effect is the ratio of the two forces, so that: C = F / G = mv2 / mgr = v2 / grBut, v = 2πrn Where, n = speed of rotation.

So, F / G = (2πrn)2 / gr = 4π2r2n2 / gr = 2 π2n2d / g ……………(1)Where, d = diameter of rotation.

Continued…..

The gravitational constant has a value of 9.807 m/s2, so that equation (1) may be

simplified to:

Centrifugal effect = 2.013 n2d

Provided that , n is expressed in s-1 and d is in meter.

From the equation, it can be drawn that the centrifugal effect is proportional

directly to the diameter, but is proportional to the square of the speed of the

rotation. Thus, if it is necessary to increase the centrifugal effect, it is of greater

advantages to use a centrifuge of the same size at a higher speed, rather than use

a larger centrifuge at the same speed of rotation.

Continued…..

Classification of Centrifugation

Types of Centrifuges Centrifuges can be classified on the basis of :• speed• temperature • use

On the basis of speed:

The "speed" of a centrifuge is measured in rotation per minute, or rpm. Centrifuges are generally divided into 3 categories based on their maximum attainable speed:

Low-speed : to maximum of 5 x 103 rpm.High-speed : to maximum of 2 x 104 rpm. Ultracentrifuges : to maximum of 105 rpm. 

On the basis of temperature :

Refrigerated centrifuges have a built-in refrigeration unit surrounding the rotor, with a temperature sensor and thermostat permitting selection of a particular temperature or a permissible temperature range that is maintained during centrifugation. Many biological samples are temperature sensitive, and centrifugation in the cold (1-4oC) is frequently required. 

Centrifuges that are not refrigerated are normally used at whatever temperature the room they are in happens to be. This is typically described in research reports as "room temperature" or “ambient temperature”.

On the basis of use :

Centrifuges

Laboratory equipment

1. Swing-out arm type

2. Angle type3. Ultracentrifuge

Commercial equipment

Perforated bowl types

Sedimentation centrifuges

Batch1. Top driven2. Under

driven

Semi continuous

Continuous or Super centrifuge

Vertical1. Simple bowl2. Bowl with

plates

Horizontal continuous decanters

Types of Centrifugation Techniques

Density gradient centrifugation

Differential centrifugation

Ultra centrifugation

It allow separation of many or all components in a mixture and allows for measurement to be made

There are two forms of Density gradient centrifugation :

Density gradient centrifugation

Rate zonal centrifugation

Isopycnic or sedimentation equilibrium centrifugation

In Rate zonal centrifugation the solution have a density gradient. The sample has a density i.e. greater than all the layers in the solution.

The sample is applied in a thin zone at the top of the centrifuge tube on a density gradient. Under centrifugal force, the particles will begin sedimenting through the gradient

Rate zonal centrifugation

The particles will begin sedimenting in separate zones according to their size shape and density.

In this type of centrifugation ,the solution contains a greater range of densities.

The density gradient contains the whole range of densities of the particles in the sample.

Each particle will sediment only to the position in the centrifuge tube at which the gradient density is equal to its own density.

In Isopycnic centrifugation separation of particles occurs into zones on the basis of their density differences, independent of time.

Isopycnic Centrifugation:

Differential centrifugation is a common procedure in microbiology and cytology used to separate certain organelles from whole cells for further analysis of specific parts of cells.

 In the process, a tissue sample is first homogenized to break the cell membranes and mix up the cell contents.

The homogenate is then subjected to repeated centrifugations, each time removing the pellet and increasing the centrifugal force.

Differential centrifugation

Ultracentrifuge The ultracentrifuge is a centrifuge optimized for spinning a rotor at very high speeds, capable of generating acceleration as high as 2 000 000 g (approx. 19 600 km/s²). There are two kinds of ultracentrifuges, the preparative and the analytical ultracentrifuge. Both classes of instruments find important uses in molecular biology , biochemistry, and polymer science.

There are different types of laboratory centrifuges:

Micro Centrifuges:Devices for small tubes from 0.2 ml to 2.0 ml (micro tubes), up to 96 well-plates, compact design, small footprint; up to 30,000 g

Clinical Centrifuges:Moderate-speed devices used for clinical applications like blood collection tubes

Multipurpose High-Speed Centrifuges:Devices for a broad range of tube sizes, high variability, big footprint

INDUSTRIAL CENTRIFUGEDefinition:

An industrial centrifuge is a machine used for fluid/particle separation.

Types:

Industrial centrifuges can be classified into two main types:

1.sedimentation centrifuge and

2. filtering centrifuges.

Sedimentation centrifuge:Sedimentation centrifuges use centrifugal force to separate solids from liquids as well as two liquids with different specific gravities.

Sedimentation centrifuges include decanter, disk-stack, solid-bowl basket and tubular bowl centrifuges.

Filtering Centrifuges:Filtering centrifuges use centrifugal force to pass a liquid through a filtration media, such as a screen or cloth while solids are captured by the filtering media. Filtering centrifuges primarily deal with perforate basket, pusher and peeler centrifuges.

TYPES:

The main parts of the Centrifuge are Bearing and Shaft, Basket, Drive and Brake BEARING AND SHAFT:The Heavy duty bearing is chosen to withstand vibratory load and centrifugal force and the shaft is made up of suitable material and duly balanced independently without the basket for higher accuracy. BASKET: The basket is made up of adequate thickness so as to withstand the loads caused by the centrifugal forces . DRIVE: The drive consists of Motor mounted at the basket casing driven through V belt with provision of the tensioning the belts. BRAKE: The Centrifuge are fitted with external shoe brakes with brake liners.

CONSTRUCTION:

Centrifuges can be used in variety of applications within the manufacturing and chemical industry.

Workshop liquids can be cleaned and be efficiently re-used by using Separator centrifuges, Examples: honing oil, quench oil, compressor oil, lube oil, hydraulic oil, wash liquids and coolants.

astewater contamination can be reduced by removal of solids (decanter) or by removing oily residues (Separator).

Sludge dewatering in a pulp and paper mill can be done more efficiently with a decanter centrifuge.

 

Industrial and Chemical

Advantages:• Centrifuges have a clean appearance and have little to no odour problems.• Not only is the device easy to install and fast at starting up and shutting down, but

also only requires a small area for operation. They can be selected for different applications. The machine can operate with a higher capacity than smaller machines. The device is simple to operate . Centrifuge has more process flexibility and higher levels of performance.

• Disadvantages: The machine can be very noisy and can cause vibration. The device has a high-energy consumption due to high G-forces. The decanter centrifuge has high equipment capital costs.

ADVANTAGES AND DISADVANTAGES:

Applications in Industry

Production of bulk drugs: aspirin is separated from its mother liquor by centrifugation.

Production of biological products:a) Separation of blood cells.b) Purification of insulin by selectively

precipitating other fraction of proteins.c) Separation of most of the proteinaceous drugs

and macromolecules.

Biopharmaceutical analysis of drugs:Centrifugation is used for separating the drugs which is essential for the evaluation of pharmacokinetic parameters and bioequivalence studies.

Application of Centrifuges

Evaluation of suspension and emulsion:

Centrifugation method is used as a rapid empirical test parameter for the evaluation of suspension and emulsion.

Ultracentrifugation are used for determination of molecular weight of serum albumin, insulin etc.

Isolation of bacterial cells, fungal and actinomycete mycelium and fermentation media is facilitated by laboratory centrifuge.

Removal of finely suspended solid matter (clarification) from aqueous or oily materials.

Ultracentrifuge can be used for separation of virus particles which has potential industrial applications.

IDENTIFICATION

2 mg halcinonide cream in a 50 mL centrifuge tube 15 ml water added and shaked to disperse 20 mL of chloroform added and shake for 5 minutes Cooling & Centrifugation Transfer the chloroform layer in a conical flask Repeat the process

ASSAY: Chromtography is used .

HALCINONIDE CREAM

IDENTIFICATION

centrifuge a portion of it and separate the solid by several portion of water

re crystalized from hot alcohol and crystals are used for identification

ASSAY Measured volume of oral suspension equivalent to 1 gram

sulfixazole Mixed with 40 mL of HCl and 25 mL glacial acetic acid swirl to dissolve and add 100 mL water Nitrite titration 0.1 M sodium nitrite equivalent to 26.73mg sulfisoxazole

SULFISOXAZOLE ACETYL ORAL SUSPENSION

References: 1.USP & 2. Centrifugation in biology and medical sciences by Philip Sheeler

Centrifugation

Application in Water Treatment

Separating chalk powder from water Removing fat from milk to produce skimmed

milk Separating textiles Removing water from lettuce after washing

it in a salad spinner Separating particles from an air-flow

using cyclonic separation

Other applications

The clarification and stabilization of wine Separation of water particles from clothes

while spin-drying in washing machines Separation of urine components and blood

components in forensic and research laboratory

http://trishul.sci.gu.edu.au/courses/7204BPS/Centrifugation_Lecture_2008.pdf

http://edusanjalbiochemist.blogspot.com/2012/11/principle-of-centrifugation.html

http://www.ruf.rice.edu/~bioslabs/methods/fractionation/centrifugation.html

http://en.wikipedia.org/wiki/Centrifugation http://www.biotecharticles.com/Biology-Arti

cle/Types-of-Centrifugation-1112.html http://s3.amazonaws.com/ppt-download/cnt

-140202014427-phpapp02.ppt?response-content-disposition=attachment&Signature=GFQHFjv656kEwTCW49YvlKTVLI0%3D&Expires=1432267338&AWSAccessKeyId=AKIAIA7QTBOH2LDUZRTQ

References

http://s3.amazonaws.com/ppt-download/b-150317231121-conversion gate01.ppt?response-content-disposition=attachment & Signature=jJDYNt%2F%2FdVE6sNv25yb2V0lsSxk%3D&Expires=1432267127&AWSAccessKeyId=AKIAIA7QTBOH2LDUZRTQ

http://s3.amazonaws.com/ppt-download/principlesandapplicationsofcentrifugation-140221075923-phpapp01.pptx?response-content-disposition=attachment&Signature=W%2B2TwJ7BZ7j%2B2zIC4zyW6Nh68YE%3D&Expires=1432267185&AWSAccessKeyId=AKIAIA7QTBOH2LDUZRTQ

http://www.ehow.com/list_5912175_types-rotor-centrifuges.html

References

Thank You