1. CENTRIFUGE WITH ADJUSTABLE SPEED AND DIRECTION OF ROTATION
BY:
AARTI SHINDE
JYOTI SHUKLA
MANISH PILLAI
SARANYA NAIR

2. INTRODUCTION
A centrifuge is a piece of equipment, generally driven by a motor, that puts an object in rotation around a fixed axis, applying force perpendicular to the axis.

3. PHYSIOLOGICAL BACKGROUND
Early instruments were hand powered, but in 1912, with the introduction of electric centrifuges, that changed. The early centrifuges were mostly used for non-biological applications, such as separating milk and collecting precipitates.

4. PRINCIPLES OF CENTRIFUGE
The centrifuge works using the sedimentation principle, where the centrifugal force is used to separate substances of greater and less density.
Basis of separation:
Size
Shape
Density

5. CENTRIFUGAL FORCE
Let us 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 =
The same body experiencing
gravitational force.
This can be expressed as,
G = mg

6. CONTINUED...
The centrifugal effect is the ratio of the two forces, so that:
C = F / G
= mv2 / mgr
= v2 / gr
But v = 2πrn
So, F / G = (2πrn)2 / gr
= 4π2r2n2 / gr
= 2 π2n2d / g (1)
g = 9.807
Centrifugal effect = n2d
Provided that n is expressed in s-1 and d is in meter.

7. METHODOLOGY In process Suspension Separation complete
Induced gravitational field
Supernatant
Precipitate
In process
Suspension
Separation complete
Pellet
Supernatant
Relative centrifugal force or Centrifugal effect

8. TYPES OF ROTORS
Fixed Angle Rotor

9. Swinging Bucket Rotor

10. BLOCK DIAGRAM LCD DISPLAY ATMEGA 8 KEYPAD POWER SUPPLY MOTOR DRIVER
TEST TUBES

11. ATmega8-Microcontroller

12. MEMBRANE KEYPAD

13. VOLTAGE REGULATOR

14. L293D

15. DC MOTOR

16. DC MOTOR

17. LCD

18. CRYSTAL

19. 10 K RESISTOR

20. 100 microfarad CAPACITOR

21. Bug strip Male
Bug strip Female

22. CIRCUIT DIAGRAM

23. APPLICATIONS OF CENTRIFUGE
Production of bulk drugs
Production of biological products
Biopharmaceutical analysis of drugs
Evaluation of suspension and emulsion
Blood plasma is separated from whole blood
Different particle size fractions are separated by using control of speed of rotation and rate of flow

24. ADVANTAGES Faster and reliable
Several specimens can be centrifuged at ago e.g. blood &urine
Not tiresome as compared to manual centrifuge machine
Safe once the specimen are enclosed into the machine

25. DISADVANTAGES Time wasting to the patient
Exhausting of the laboratory technician
Specimens may spill out of the test tubes
The capacity is limited.

26. CONCLUSION
Thus, we can see that the centrifuge machine is an essential medical device for every biological and clinical laboratory as well as medical practice.
The centrifuge may seem a rather common machine, but newer models have become more complex, as higher speeds have become necessary for certain processes and applications and as more precise controls are needed.

27. BIBLIOGRAPHY Basic medical laboratory techniques - Page 69
by Barbara H. Estridge, Anna P. Reynolds, Norma J. Walters
Fundamentals Of Bioanalytical Techniques And Instrumentation - Page 118
by Ghosal & Srivastava
Basic Clinical Laboratory Techniques - Page 85
by Barbara H. Estridge, Anna P. Reynolds

29. Thank You…