GENERAL INFORMATION
Basic rules for laboratory
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In laboratory, rules for classrooom hours are also valid. A quiet and careful working
duration should be provided.
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It is forbidden to have food and beverages in the laboratory.
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Laboratory coat is mandatory. Students without the coat will not be allowed to
participate in the experiment. In accordance with safety and hygiene rules, hair must be
tied up in the laboratory. While working with biological samples, gloves should be used
and care should be taken to use protective glasses and masks when necessary.
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The prepared laboratory handbooks should be carefully read before the experiments. A
quiz that tests the theoretical and practical knowledge about the subject is applied to the
students before the experiment.
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Solutions and laboratory equipment necessary for the experiments are ready to use on
the benches.
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Cleaning of used glassware and tools is done with tap water and detergent, rinsed with
pure water. Specialized cleaning methods are used for biological samples. Used pipette
tips are collected in a separate container and discarded into appropriate garbage bins.
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After the experiment, students are obliged to deliver a laboratory report as an
individual / group to the instructor.
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When leaving the laboratory , glassware and tools should cleaned, solutions should
carried to the bench shown by the instructor.
Laboratory safety
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The warnings of the instructors should be followed carefully before starting the
experiments.
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The storage conditions of the solutions should be taken into account when using these
material (Light sensitivity,screwed cap…)
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Care should be taken to use a separate and clean pipetting tool for the transfer of each
solution.
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All materials to be used in the experimental process, especially the test tubes, should be
marked and organized properly.
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Pipetting should be carried out sequentially by instructors directions.
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Do not pipet by mouth use a pipet bulb.Do not pipet directly from reagent bottles and
do not return unused reagents to stock solutions.
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Do not smell, inhale and taste any of solutions
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Notify the instructor if any accident occurs. In case of contact / injury with chemical
material, the area should immediately be washed with water.
BASIC LABORATORY EQUIPMENT
Analysis are classified as:
1. Qualitative analysis: These give the result of the experiment based on the physical
properties (non-numerical) such as the presence of a precipitate or a color change.
2. Quantitative analysis : Gives the result of the experiment in numerical values (volume
change, concentration…)
Some abundantly used basic materials and devices are given below.
A. DEVICES
• Vortex: Used especially for homogeneous mixing in the tube. An electric motor
provides the mixing of the material by running the upper material in circular motions.
• Magnetic stirrer : Magnetic stirrers allow liquids to be mixed with the effect of a
magnetic force and also heat the solution .
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• Centifuge: Separates the mixtures by precipitation with centrifugal force . Heavy
particles are collected at the bottom of the tube at the rotational speed. The lower parts
are called "precipitate" and the upper liquid part is called "supernatant".It is widely used
in laboratories and for example centrifugation of blood is a common used preparation
method in biochemical studies.
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B. PLASTICS/GLASSWARE
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Beaker : These are cylindrical glass containers with wide mouths suitable for
transferring liquids. Although there are various volumes / sizes, scales are not sensitive
enough to be used for concentration and volume measurements.
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Erlenmeyer flask : They are narrow necked, cone shaped glass containers especially
used in titration. Similar to the beakers, these materials are not accurate to scale
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Test tubes : There are test tubes in various volumes, shapes and features (plastic, glass,
heat resistant, with / without lid…). Volume scales are not accurate.
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Volumetric flask: Glass materials used for preparation of standard solutions and
certain concentrations. There are different volumes. The ones with lid are also suitable
for storage
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Volumetric cylinder: Materials made of plastic or glass material for volumetric
measurement. They have different types with measurement sensitivity / accuracy.
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Pipette: These are laboratory tools to draw very precise volumes of liquid and transfer
it to another container. It is important to choose proper pipet for the study in terms of
correct volume .Pipettes can be classified according to these characteristics as follows:
➢ Glass pipettes: They are graduated pipettes made of glass, produced in variable
(a) or fixed volumes (b). They are not suitable to be used use in volume transfers
below 1ml in terms. They can be washed and used again.
a) Variable
b) Fixed
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➢ Pasteur Pipette: They absorb the liquid with the pumping unit located at the
head. Whole plastic pipettes are disposable, while two-piece pasteur pipettes
with a plastic pumping tip and a glass draw tip can be washed and reused
a)
Plastic
b) Glass
➢ Automatic Pipettes: These pipettes allow working in very low volumes (l-ml
range). They have adjustable and fixed types and with disposable pipette tips.
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Piston: Performs drawing the sample of the adjusted volume to the pipette tip and
emptying it.
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Tip dispenser : Untouched removal of used tips
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Volume adjustment knob: Adjustment of the volume of liquid to be withdrawn.
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Volume display screen: Screen showing the adjusted volume.
In these pipettes, the adjusted volume is taken to the pipette tip with the a partial vacuum
by pressing the piston. Then the liquid is transferred to another place by pressing the piston.
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Pipet bulb : They are plastic / polypropylene laboratory tools used for pipetting with the
help of vacuum in glass pipettes.
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