This document describes various basic laboratory equipment and their uses. It discusses the microscope in detail, including its parts, principles of magnification and resolution, and types. It also describes other common equipment like the centrifuge, glassware, incubator, autoclave, ovens, water bath, and biosafety cabinet. Finally, it covers specimen collection, transportation, storage, and rejection criteria.

1. 2
BASIC LABORATORY
EQUIPMENTS

2. BASIC LABORATORY EQUIPMENTS
Learning Objective:
At the end of the lessen the student should be able to:
 Identify the different component and uses of the
microscope .
 Manipulate the different parts of the microscope .
 Identify the different types of laboratory equipment.

3. Basic laboratory equipments
1. Microscope
2. Centrifuge
3. Glass wares
4. Other equipements

4. 1. The Microscope

6. The Microscope….
It is an instrument that enables us to visualize minute objects that cannot be
seen by our naked eyes.
Working principle of a microscope
1. Magnification- enlarging size .
 It uses lenses to enlarge size.
Objective x Eye piece = Total
Magnification Magnification magnification
10x 10x 100 times diameter
40x 10x 400 times diameter
100x 10x 1000 times diameter

7. Cont….
2. Resolution-
 It is the ability of a microscope to produce distinct images of two adjacent points
 It is ability to show details
• Measured by µm, mm, nm…
Resolving power:
• Human eye-------------------- 0.25 mm
• Light Microscope------------- 0.25µm
• Electron Microscope--------- 0.5 nm
• Note :In general, the greater the magnification, the greater
the resolution, but this is not always true.

8. Cont…
• The resolution of a lens depends on its:
1. Physical properties
– summed up in a value known as numerical aperture of a lens
2. The wavelength of the light
 depends on the color of light
The shorter the wave length the higher is resolution power
– The numerical aperture of a lens is depending up on two parameters:
the angle of the incidence of the light on to the lens
the refractive index of the glass of which the lens is composed

9. Cont…
 resolution can be increased in three ways.
1. The easiest method is to increase the angle of light incidence,
by altering the position of the sub stage condenser.
2. The refractive index can be maximized by using specially
manufactured lenses, and by controlling the medium through
which the light travels, i.e using oil with lenses designed for
this purpose.
3. By decreasing the wave length of light used.

10. Classification of microscope
 microscopes differing on the principle on which magnification is based.
I. Light microscopes;
 Use optical lenses
 use light waves to produce the magnified image.
 the limit of magnification 1,500 x - 2,000 x
Include:
1. Bright field microscope
2. Dark field microscope
3. Fluoresce Microscope
4. Phase contrast microscope
II. Electron microscopes
 Use magnetic lens
 employ a beam of electrons

11. 1.The frame work
 Base(Foot)- - is the rectangular part up on
which the whole instruments rest.
 Arm(stand) -- to which the base, body and
stage are attached.
 Stage - where the slide or specimen is placed.
2. The illumination system
Components of the illumination system:
 Light source & intensity control
 Iris diaphragm
 Condenser
Parts of the microscope

12. Source of Illumination
• 1. Day light: microscope must not be used in
direct sunlight.but Ordinary daylight may be
sufficient for some work.
• 2. Electric Light: Ordinarly 60 watt electric
bulb placed about 18 inches from the
microscope is sufficient for most routine work.
• Quartz halogen is very good light source

13. Cont…
3. Magnification system
 Ocular (eyepiece)
–Based on the number of oculars:
oMonocular Microscope - only one ocular
oBinocular Microscope – two oculars
oTrinocular Microscope – three oculars

14. Cont…
Objectives
i. Low power (10x) objective
 Used for the initial scanning and observation in most
microscopic work.
 When using the 10x objective
– Close iris diaphragm completely .
– Lower the condenser .
ii. High-dry power (40x) objective
 Is used to study unstained specimens such as stool and urine
sediment for more detailed examination.
 When using 40x objective:
- Open iris diaphragm half way
- Raise condenser half way

15. Cont…
iii. Oil immersion (100x) objective
 Routinely used for morphologic examination of blood films
and microbes.
 Oil is used to increase the intensity of light.
 Increase refractive index
 When using the 100x objective:
• Raise the condenser completely .
• Open the iris diaphragm completely.

16. Cont…
4. Focusing system
• Coarse and fine focusing adjustments
– Course adjustment: - The course focusing
adjustment is controlled by a pair of large knobs
positioned one on each side of the body. Give
rough image.
– Fine adjustment: - it moves the stage so slowly.
Give clear image.

17. Cont…
• Condenser adjustments: - The condenser is focused usually
by rotating a knob to one side of it.
– This Moves the condenser up or down.
– The condenser aperture is adjusted by the iris
diaphragm, which is found just below the condenser.

18. 2.Centrifuge
• It is an apparatus that is used to separate solid materials
from a liquid suspension by means of centrifugal force.
• The sediment particles (cells ,bacteria, casts, parasites
etc) suspended in fluid by exerting a force greater than
that of gravity deposited in the order of their weight.
• A body is rotated in a circular movement at speed. This
creates a force that drives the body away from the
center of circular movement.

19. Types of centrifuge
A. Micro centrifuge - used for spinning small tube as in blood
bank laboratories. E.g. micro hematocrit centrifuge.
B. Medium size centrifuge – used to centrifuging urine specimen.
C. Large centrifuge – widely used in bacteriology & clinical
chemistry laboratories which are designed to centrifuge volumes
up to 200ml at maximum speed of 3000-4000rpm.
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20. Cont…
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21. Hematocrit centrifuge
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22. 3.Glass wares
 are apparatus used for the measurement and transfer of
liquids.
 Should be made of borosilicate glass, which is resistant to
heat.
 Common glass wares used in clinical laboratory include:-
-Test tubes
- Graduated measuring cylinders.
- Volumetric flasks.
- Beakers
- Petri dishes
- Pipettes
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23. 4.Other Equipments
INCUBATOR
• Incubation at controlled temperature is required for
bacteriological cultures, blood transfusion, Serology,
Hematology and clinical Chemistry tests.
• For bacteriological cultures, an incubator is required
whereas for other tests a dry heat block or a water bath
may be used
• For the incubator, the air inside is kept at a specific
temperature (usually at 370c). When tubes are kept
inside the incubator, they take the temperature of the
incubator.

24. Autoclave
– Autoclave is an instrument that
operates by creating high
temperature under steam
pressure.
– Autoclaving is the most
common, effective, reliable and
practical method of sterilizing
laboratory materials.
– Temperature of 1210c, which
will kill spores with in 15
minutes and at 15 psi /pound/.
– At this particular temperature,
pressure and time, all forms of
lives are destroyed.
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25. OVENS
– Hot - air ovens are instruments that are used for drying
of chemicals and glass wares.
– They are also used for the sterilization of various glass
wares and metal instruments.
– They consist of double walls that are made of copper
or steel.
– They are heated by circulation of hot air from gas
burners between the metal walls or by electrical mains.
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26. WATER BATH
• The water bath, like the incubator, is required for controlled
temperature (from 20o
C to 100o
C) incubation of culture and
liquids, and many other laboratory tests.

27. Colorimeter/ (Photometer)
• is an instrument used to measure the
concentration of a substance in a sample by
comparing the amount of light it absorbs with
that absorbed by a standard preparation
containing a known amount of the substance
being tested.

28. Mixers
• are instruments used for preparation of reagents for mixing
or dissolving purpose.
• Also used for homogenization.

29. Refrigerators
– Refrigerators are physical means of preserving various
laboratory specimens.
– They suppress the growth of bacteria and maintain the
specimens with little alteration.
– In addition to this, they are also used in the medical
laboratory to preserve some reagents such as:
– tests kits,
– Culture media are also preserved
– Blood grouping anti sera and others which
are kept in the refrigerators to prevent their
deterioration.

30. Biological safety cabinets/BSC
– Are the principal equipment used to provide physical
containment.
– Are used as primary barriers to prevent the escape of
aerosols into the laboratory environment.

31. 3.Specimen collection, transportation and
storage
• Definition of specimen
• Specimen is a part taken to determine the character of the
whole.
Safety materials during collection, processing & transportation
• Masks (e.g. sputum)
• Gloves
• Protective eye ware (goggles)
• Protective clothing (gown)

32. Cont…
• Several different kinds of specimens are used
routinely in the clinical laboratory.
These are:
• Blood
• Urine
• Stool
• Sputum
• Pus (discharge)

33. Cont…
• Throat, eye, ear, vaginal swabs
• Skin snips
• Body fluids (pleural, pericardial, peritoneal,
synovial, and cerebro spinal)
• Hair, nail, coetaneous tissue
• Biopsy tissue from an organ.

34. Cont…
• Correct treatment depend on accurate result.
• Accurate result depend on quality specimen.
• Quality specimen depend on proper :
 Collection .
 Transportation.
 Processing of specimens .

35. Basic Concept in Specimen Collection
1. Site selection
a. Clinician
• Should locate right anatomic site & select appropriate tests &
specimens based on:
 - Physical examination (sign & symptoms)
 History of patient.
 - Radiological examination.
b. Laboratory personnel
• Should collect specimens from actual infection site with little
external contamination by using :
Aseptic technique
• To prevent contamination of specimen &
• To protect the patient from infection.
Sterile container
• . Should collect specimens from right site

36. 2. Volume of specimens
• Collecting & processing too little specimen will give us lower
sensitivity.
• Collecting adequate volume:
o enhance recovery of the pathogen.
o enable to perform all procedures required or to
permit complete examination.
 For example;
o Sputum: 5 -10 ml for mycobacterium examination.
o Blood:
 Serology: minimum 2 - 3 ml.
 Culture: 10 – 20 ml (adult) & 1-5ml (infant).
o CSF: 5 – 10 ml.

37. 3. Time of collection
• Provide best chance of recovery of the
causative agent .
• Sputum & urine - early in the morning soon
after the patient awaken.
• Blood - when the patients temperature begins
to rise.

38. Cont…
4. Collect specimens before the administration of antimicrobial
Because antimicrobials limits recovery of pathogens.
5. Age of specimens
Age of the specimen directly influences the recovery of
protozoan organism.
6. Stage of the disease at which the specimen is collected
 Enteric pathogens are present in great numbers during the
acute or diarrheal stage of intestinal infection.

39. 7. Labeling
Make sure that you are collecting/drawing the sample
from right person first.
Then label with:
 Patient name.
 Unique identification number.
 Patient demographic information.
 Specimen collection date.
 Specimen collection location.

40. General Specimen Rejection Criteria
• Un-labelled Specimens.
• Incorrectly labeled (mislabeled) specimens.
• Incorrect container or Preservative.
• Insufficient specimen for procedure.
• Unsuitable Specimen for Procedures.

41. Specimen Transportation
 Required when:
Specimens are to be sent to referral laboratory.
 For teaching purpose.
 For Quality assurance.
 Unavailability of trained personnel around the
collection site.
 Specimens are collected in the field.
 Lack of time to examine within the recommended
time due to laboratory workload.

42. Cont…
This transportation is made by using different preservation
methods:
– Physical
– chemical.
chemical method of preservation is most common.
 Purpose of preservation :
o Maintain protozoan morphology
o Prevent development of helminthes eggs & larvae
o Maintain viability of microorganisms
o Prevent overgrowth of normal flora
o Prevent instability of solutes & degeneration of
sediments (e.g. urine)

43. Cont…
 Specimen packaging
o Screw container tops on firmly
o Wrap in absorbent wadding to absorb any fluid
leakage
o Place in a self-sealing plastic bag
o Place the request form into the secondary pocket of
the specimen bag.
o Hazard labels with internationally accepted biohazard
label (HIGH RISK).
o Pack specimens in strong cardboard box or a grooved
polystyrene box.
o Seal with self-adhesive tape.

44. Specimen Storage
o Urine can be stored at either freezer or refrigerator at +4
oc.
o Blood samples should be kept at +4 oc.
o Serum & plasma can be stored either frozen or at +4oc.
Note: They should not be unfrozen until dispatch to the
laboratory.