The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdf
lec4- Micropipette- biotechnology استاذ حيدر.pptx
1. Micropipette
It is one of the laboratory tools used to deal with small volumes of liquids
(microliters. (
There are several types of micropipette :-
1- Fixed pipette mL 500
2- -The moving pipette has several sizes, including (0.5-100), (20-200) ml, and
1000 ml.
2.
3. Parts -: Micropipette
-
• The metal part
• The plastic part
• -The button to remove the confusion
• and the drive zeroes
• The method of work :
-
• Micro pipettes should be sterilized with alcohol and wiped clean before use. The volume required to be
withdrawn from the sample must be set by the drive zeroes located | at the top of it. Tabs must be
installed in the correct place. The bag must be pressed to empty the air. The lower part of the tapes must
be immersed in the sample, and the required amount must be withdrawn. The tapes should be placed in
an inclined position in the event that the sample is emptied. Previously used samples should be discarded
to be replaced in a new sample .
4. Centrifuge :-
•
Centrifuge: It is a device that separates solids
from liquids or separates liquids according to
their different densities by means of rotational
movement at a high speed to create a
centrifugal force where the heavier particles
are directed.
5. Types of centrifuges
• 1- high speed centrifuge.
• 2- laboratory centrifuges.
• 3- standard centrifuges.
• 4- High speed and refrigerated centrifuges.
• 5- Manual centrifuges.
6. working principle of the centrifuge:
• The device begins with a rapid rotation, while the movement of the particles inside the
mixture remains straight, which causes the particles to rush outward, so the larger the
particles are, the faster they rush out, and thus the components of the mixture are separated
from each other, as the large particles are placed in specific and different places within the
device. In laboratories can be installed on in a certain place. It contains holes made at a
certain angle to carry samples. Because the tubes are installed at a certain angle and the
effect of the centrifugal force is horizontal. Where the particles move before they the wall of
the tube, allowing the dense material to leak out at the bottom. There is a type of fixed-angle
or oscillating rotary device that can be used to separate blood components.
8. The main factors that cause unbalanced rotor during centrifugation:
• The centrifuge is a relatively complex machine. The centrifuge contains a
cylinder that rotates around its axis at a high speed and is used to separate
particles of different nature from each other. Ejector failure occurs due to
excessive rotor imbalance. And an error in weighing the sample, making
sure the sample cover is well.
9. How to operate the Centrifuge
• 1- The device must be placed on a stable and solid base to avoid vibration.
• 2- Turn on the power key.
• 3- Place the required sample in the designated place in a balanced manner.
• 4- Press the function selection button to set the temperature, speed and time.
• 5- The top cover of the device must be covered.
• 6- Press the Start button.
• 7- After the device has completely stopped rotating open the cover.
• note :- If the device vibrates during operation, the electric current must be cut off
•
immediately
10. Chemistry Lab Basics :- Some basics of chemistry Lab
•
1- Protective glasses must be worn.
•
2- Wearing a bra while working inside the laboratory.
•
3- Wearing gloves every time you use chemicals because they cause irritation.
4- It is forbidden to put contact lenses in the laboratory because they absorb fumes
and are difficult to remove in emergency cases.
11. The most important tools and glassware used in :
• 1- The electronic balanceof the balance of chemical.
• 2 - centrifuge.
• 3 - pipette.
• 4- Standard beaker.
• 5- Burette.
• 6- Conical flask.
• 7- A glass cup.
• 8- Cylinder included.
• 9- Test tube.
