PROPER PIPETTING TECHNIQUE

Question 1

are instruments used to measure
liquid ranging between volumes
of 0.2-10000ul and transfer it
from one sample container to
another.

Answer 1

Micropipettes or pipettes

Question 2

Micropipettes or pipettes are
instruments used to measure
liquid ranging between volumes
of______ and transfer it
from one sample container to
another.

Answer 2

0.2-10000ul

Question 3

• This is a basic liquid-handling
instrument for almost all
scientific laboratories.

Answer 3

Micropipette

Question 4

• Mastery of their principles is key
to effective scientific research
and analysis.

Answer 4

MICROPIPETTES

Question 5

• They are crucial in lab settings
like molecular biology and
diagnostics, precisely transferring
tiny liquid volumes.

Answer 5

MICROPIPETTES

Question 6

Types of Micropipettes:

Micropipettes can be categorized based on their design and functionality:

Answer 6

Number of Channels
Volume Adjustment
Operating Mechanism

Question 7

2 types of number of channels

Answer 7

Single-channel

Multi-channel

Question 8

Has 1 channel to aspirate and dispense
liquid, allowing handling of one sample at a time.

Answer 8

Single-channel

Question 9

Can handle 8, 12, or 16 samples
simultaneously by attaching multiple tips.

Ideal for high-throughput labs.

Answer 9

Multi-channel

Question 10

Multi-channel

Can handle_______ samples
simultaneously by attaching multiple tips.
Ideal for high-throughput labs.

Answer 10

8, 12, or 16

Question 11

2 types of volume adjustment Micropipette

Answer 11

Fixed volume
Variable volume

Question 12

Aspirates and dispenses a fixed volume
without adjustment;

Answer 12

Fixed Volume

Question 13

provides consistent and accurate results for repetitive pipetting.

Answer 13

Fixed volume

Question 14

often includes a volume lock feature for
enhanced accuracy and safety.

Answer 14

Variable Volume

Question 15

Allows users to manually adjust the
volume within a given range;

Answer 15

Variable Volume

Question 16

2 types of operation mechanisms

Answer 16

Mechanical
Electronic or digital

Question 17

Standard piston-driven pipettes where users manually set the volume and apply thumb pressure to operate.

Answer 17

Mechanical

Question 18

Features digital controls and programmability to reduce human error,
with an electronic display;

Answer 18

Electronic

Question 19

ideal for high-throughput labs requiring reproducibility.

Answer 19

Electronic

Question 20

Components of MICROPIPPETE

Answer 20

Plunger
Tip ejector
Volume adjustment dial
Volume display
Shaft
Disposable tip
Piston
Friction ring
Springs
O-ring

Question 21

: autoclavable attachments for
the uptake and dispensing of liquids using a pipette.

Answer 21

• Disposable Pipette Tip

Question 22

: Holds the pipette tip in place.

Answer 22

• Shaft

Question 23

: Shows the set volume.

Answer 23

• Volume Display

Question 24

: Sets the desired volume.

Answer 24

• Volume Adjustment Dial

Question 25

: Removes the disposable pipette tip.

Answer 25

• Tip Ejector

Question 26

: Controls liquid aspiration and dispensing.

Answer 26

• Plunger

Question 27

• are a consumable product that are purchased separately from a pipette. It is important to use the proper type of tip as your pipette may not work correctly without it.

Answer 27

Disposable Pipette Tip:

Question 28

The internal parts of a micropipette:

Answer 28

Piston Friction ring O-ring Springs

Question 29

Ensures a tight seal to prevent air or liquid leakage, crucial for precision.

Answer 29

• O-ring:

Question 30

Provide the necessary tension for the piston to return to its original position after dispensing.

Answer 30

• Springs:

Question 31

Helps regulate the smooth motion of the piston.

Answer 31

• Friction Ring:

Question 32

Drives the liquid aspiration and dispensing process.

Answer 32

• Piston:

Question 33

Common pipette sizes

Answer 33

P2 P10 P20 P100 P200 P1000

Question 34

Common Micropipette Sizes Volume Range??? P2 P10 P20

Answer 34

0.2-2 uL 1-10 uL 2-20 uL

Question 35

P100 P200 P1000

Answer 35

20-100 uL 20-200 uL 100-1000 uL

Question 36

How does a Micropipette work? Micropipettes operate on the principle of_______

Answer 36

air displacement

Question 37

The volume of air displaced corresponds to the selected aspiration volume.

Answer 37

Air Displacement Pipette

Question 38

Plastic tip contains an integrated piston.

Answer 38

Positive Displacement Pipette

Question 39

Micropipettes operate on the principle of ***air displacement.*** They consist of a plunger connected to an internal piston, which moves to two distinct positions:

Answer 39

• Filling position • Dispensing position

Question 40

______ position • When the plunger is depressed to the first stop, ***the internal piston displaces a volume of air (air displacement) equal to the desired volume shown on the volume indicator dial.*** • This air displacement creates a vacuum inside the pipette tip, allowing liquid to be drawn up when the plunger is slowly released while the tip is submerged in the liquid.

Answer 40

Filling position

Question 41

________ position • The second stop on the plunger is used solely for ______ the contents of the tip. • Pushing the plunger to the second stop forces a burst of air through the tip, ensuring that all liquid, including any residue, is fully expelled.

Answer 41

Dispensing position

Question 42

First stop - Second stop -

Answer 42

Air displacement Dispensing

Question 43

5 Steps of Micropippeting:

Answer 43

Set the volume Attach pipette tip Aspirate the liquid Dispense the liquid Eject the tip

Question 44

Errors to avoid

Answer 44

Misaligned or improperly secured pipette tips Inconsistent plunger pressure during operation Submerging the tip too deeply or not deep enough in the liquid Holding the pipette at an incorrect angle

Question 45

Misaligned or improperly secured pipette tips

Answer 45

Ensure tips are properly attached to avoid leaks or inaccuracies.

Question 46

Inconsistent plunger pressure during operation

Answer 46

Apply consistent pressure to prevent uneven aspiration or dispensing.

Question 47

Submerging the tip too deeply or not deep enough in the liquid

Answer 47

Submerge the tip just ***2–3 mm*** below the liquid surface to avoid air intake or excess uptake.

Question 48

Holding the pipette at an incorrect angle

Answer 48

Keep the pipette vertical to maintain accuracy

Question 49

Best practices in micropipetting

Answer 49

Pre-wet the pipette tip before use Pipette slowly to avoid bubbles and ensure consistent aspiration Always use the correct pipette and tip size for the volume being handled

Question 50

Improves accuracy by equilibrating the pipette tip with the sample liquid.

Answer 50

Pre-wet the pipette tip before use

Question 51

Prevents errors caused by trapped air or uneven liquid handling.

Answer 51

Pipette slowly to avoid bubbles and ensure consistent aspiration

Question 52

Ensures precision and avoids overloading the pipette.

Answer 52

Always use the correct pipette and tip size for the volume being handled

Question 53

Proper Micropipette Handling and Care

Answer 53

1. Never force the volume adjustment dial beyond its range. 2. Before storing, set the dial to the highest setting to release spring tension. 3. Always store the pipette properly: • Keep it vertically in a stand to prevent internal damage. • Avoid horizontal storage to prevent liquid entry. 4. Clean the exterior with a lint-free cloth and mild detergent or 70% ethanol. 5. Handle with care; accidental drops may require recalibration. 6. Prevent liquid from entering the pipette body to avoid buildup and inaccuracies. 7. Regular calibration is essential for accuracy.