Chapter 1&2 Introduction & Centrifugation

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ASSESSMENTS :

5 QUIZZES 10%

2 ASSIGNMENTS 20%

MID SEM EXAM 30%

FINAL EXAM 40%


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CHAPTER 1 INTRODUCTION

CHAPTER 2 CENTRIFUGATION

CHAPTER 3 CHROMATOGRAPHY

CHAPTER 4 ELECTROCHEMISTRY

CHAPTER 5 MICROSCOPE

CHAPTER 6 SPECTROMETRYCHAPTER 7 ELECTROPHORESIS

CHAPTER 8 HEMATOLOGY ANALYSIS

CHAPTER 9 IMMUNOCHEMISTRY ANALYSIS

CHAPTER 10 FORENSIC ANALYSIS


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CHAPTER 1 : INTRODUCTION

BIOMEDICAL INSTRUMENTATION

Devices that can be used to make measurements of biologic or

medical quantities and give quantitative results

BASIC BIOMEDICAL INSTRUMENT

PHYSIOLOGIC SENSOR PROCESSOR DISPLAY OBSERVER

SYSTEM STORAGE


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FUNDAMENTAL RULES OF BIOMEDICALINSTRUMENTATION

Minimum disturbance to physiologic

Sensor must be at physiologic variable value

Maintain simplicity


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IMPORTANT INSTRUMENTATION TERMS

SENSITIVITY - Change in output as a function of achange in input

STABILITY

Consistency in output for a constantinput

SPECIFICITY Ability to distinguish desired variable

from other competing variables

ACCURACY the closeness of the instrumentoutput to the true value of the measured quantity


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PRECISION The smallest change in a variables thatcan be correctly measured

RESOLUTION The degree of fineness with which ameasurement can be made

REPRODUCIBILITY Same output for the same input


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TRANSFER CHARACTERISTIC

SENSITIVITY- change in output as a function of a changein input

Instrument

Output

Variable Measured


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STABILITY Consistency in output for a constantinput

Variable

Time


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SPECIFICITY Ability to distinguish desired variablefrom other competing variables

Instrument

Output

Variable Measured


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ACCURACY the closeness of the instrument output tothe true value of the measured quantity

Instrument

Output

Variable Measured


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ACCURACY

The accuracy of the instruments can be measured by usingthis calculation:

Percentage of true value = measured value true value x 100true value


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ACCURACY vs PRECISION


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POSSIBLE TYPES OF TRANSDUCERS

To convert the input signal to a form which can beconveniently processed

Mechanical Thermal

Electrical Acoustic

Mechanical Hydraulic


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TYPES OF SENSOR

PHYSICAL-THERMOMETER

BIOANALYTICAL

-GLUCOSE SENSOR

CHEMICAL-OXYGEN

ELECTRODE


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SINGLE CONVERSION SENSOR

PHYSIOLOGIC SENSOR ELECTRICAL

VARIABLE SIGNAL

PARTIAL CLARK ELECTRICAL

PRESSURE ELECTRODE CURRENT

OF OXYGEN

BODY THERMISTOR ELECTRICAL TEMPERATURERESISTANCE


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MULTIPLE CONVERSION SENSOR

PHYSIOLOGIC INTERMEDIATE SENSOR ELECTRICAL

SENSOR VARIABLE SIGNAL

BLOOD DIAPHRAGM DISPLACEMENT ELECTRICAL

PRESSURE DISPLACEMENT SENSOR SIGNAL

SERUM HYDROGEN H2O2 SENSOR ELECTRICAL

GLUCOSE PEROXIDE SIGNAL


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EXAMPLES OF FAMILIAR BIOMEDICALINSTRUMENTATION
http://rds.yahoo.com/_ylt=A0S020oJhERK.8UAFwWjzbkF/SIG=127iohu06/EXP=1246090633/**http:/www.valuemed.co.uk/acatalog/on-call_plus.gifhttp://rds.yahoo.com/_ylt=A0S020ykgkRKlX4AtyyjzbkF/SIG=127h98g72/EXP=1246090276/**http:/www.flickr.com/photos/tessawatson/383858436/http://rds.yahoo.com/_ylt=A0S020ykgkRKlX4ApiyjzbkF/SIG=12qa8o9sv/EXP=1246090276/**http:/img.alibaba.com/photo/50071008/Digital_Clinical_Thermometer.jpghttp://rds.yahoo.com/_ylt=A0S020xCgkRK.4YAdaCjzbkF/SIG=126a5o8s0/EXP=1246090178/**http:/www.flickr.com/photos/jessmercer/358719372/


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STANDARDS OF MEASUREMENTS

-Defined as the physical representation of the unit ofmeasurement (S.I. unit)

-For example : kilogram was originally defined as the

mass of a cubic decimetre of water at its temperature ofmaximum density at 4 C


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CALIBRATION

-Is the act or result of quantitative comparison between

a known standard and the output of the measuring

system measuring the same quantity

-Calibration curve is a references standards withknown values to cover the range of interest


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ERROR

-Defined as the differences between the measured and thetrue value

ERROR

systematic/cumulative Random error

error - arises from our

- can in principle be ability to makediscovered and corrected physical measurement

- always present and

cannot be corrected


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Systematic/cumulative Error

Instrument Environmental Zero error

Error Error

Loading

Error


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Instrument error

-Poor design of instrument-Can be avoided by selecting a suitable instrument

for a given application and calibrating instrument

using a suitable standard

Environmental error

-The condition of environment such as windy, rainy,hot .

-Can be avoided by doing the measurement in close

room.


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CHAPTER 2 : CENTRIFUGATION


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CENTRIFUGATION

-Device for separating particles from a solutionaccording to their size, shape, density,viscosity ofthe medium and rotor speed-Centrifuge have been used since middle 1800-Hand-driven (only after 1912, it is electricallydriven)

THEORY OF CENTRIFUGATION

-Sedimentation of a molecule is influenced by :a) properties of the molecule (size,shape,density)b) properties of the solvent (density, temperature)c) interactions between solute molecules & solvent

material


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FORCES IN CENTRIFUGATION

As the rotor spins in a centrifuge, centrifugal force isapplied to each molecule in the sample :

CF = Mw2r

M = mass (particle weight/molecular weight)

w = angular velocity

r = distance from the axis of rotation


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-The larger the molecule or the faster thecentrifugation or the longer the axis of rotation,

the greater the centrifugal force and the rate ofsedimentation

-Two forces act to counteract the centrifugal force are

bouyant force and frictional force

-A sedimenting molecule moves faster and faster in a

centrifugal field until :

Centrifugal force = bouyant force + frictional force


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TYPES OF CENTRIFUGES

Desktop clinical centrifuges

-Simplest & least expensive

-Max speed of most desktop centrifuges is below 3000 rpm

-Most operate at all temperature-Typical application : rapid sedimentation of blood samples

Highspeed centrifuges

-Operating up to speeds of 20,000 to

25,000 rpm

-Typical application : collect larger organelles


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Ultracentrifuges

-Typical application : separation of the major

lipoprotein fractions from plasma

-4 principles :

a)Drive and speed control : flexible drive shaft system,an overspeed system

b)Temperature control : infrared temp. sensor

c)Vacuum system

d)Rotor : swinging bucket rotor & fixed

angle rotor


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TYPES OF CENTRIFUGATION

-Analytical-Preparative

ANALYTICAL

-measuring physical properties of sedimenting particlesuch as molecular weight

PREPARATIVE-To isolate specific particles which can be reused

-Three types : rate zonal, differential, isopycnic


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Analytical

Uses small sample (less than 1 ml)

Built in optical system to analyze progress of molecules during

centrifugation Uses relatively pure sample

Used to precisely determine sedimentation coefficient and MWof molecules

Preparative

Larger sample size can be used

No optical read out collect fractions and analyze them after therun

Less pure sample can be used Can be used to estimate sedimentation coefficient and MW

Generally used to separate organelles and molecules. Mostcentrifugation work done using preparative ultracentrifuge


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Density gradient centrifugation

1) Rate zonal centrifugation

-Separates molecules based on molecular weight-Used to separate various types of macromolecules suchas different types of RNA, DNA

2) Isopycnic centrifugation-separate molecules based on density

-used to separate cell organelles


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Differential centrifugation

-Start with a uniform mixture of sample

-Centrifuge to obtain pellet of heavier molecules andsupernatant

-Take supernatant & recentrifuge to pellet the next

largest particle-Commonly used for separation of organelles


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CLASSIFICATION OF CENTRIFUGATION BASED ONRATE/SPEED

Ultracentrifugation - x> 20,000 rpm

Super speed ultracentrifugation 10,000


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ROTOR

-Two types of rotor : swinging-bucket rotor andfixed-angle rotor

SWINGING-BUCKET ROTOR

Consist of a rotor from which

hang three to six free moving

bucket that hang vertically when

the rotor is at rest


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ASSIGNMENT 1

TITLE : INTRODUCTION TO LABORATORY

INSTRUMENTS

Font : 11, Arial, 1.5 spacing

Pages : Maximum 10

Cover : Green (Name, ID Num., Lecturers name,Group, Dateline)

Dateline : 06 JULY 2011


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SAMPLE

INSTRUMENTATIONSGS 1102

ASSIGNMENT 1

INTRODUCTION TO LABORATORY INSTRUMENTS

NAME :MATRIC NO :LECTURER :GROUP :SUBMISSION DATE :

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Chapter 1&2 Introduction & Centrifugation