A micropipette is a common and a very essential chemical laboratory instrument used to precisely and accurately transfer liquid volumes in the microliter range. Micropipettes are available in single and multichannel configurations. Multichannel micropipettes are ideal for ELISA (diagnostic testing) as well as molecular screening studies of kinetics and DNA amplification. Single channel micropipettes are used in chemical laboratories that conduct a thorough research in microbiology, molecular biology, cell culture, immunology, biochemistry, analytical chemistry, genome study and genetics.
Components of a micropipette
Micropipettes come in a variety of shapes and sizes. A few characteristics are shared by all micropipettes. The plunger, digital display, and tip cone, as well as the tip ejector and grippy, are all part of this. Certain micropipettes include a calibration tool as well as a micropipette stand as an option.
The Plunger: A plunger is the topmost part of a micropipette that is used to expel and also collect the desired amount of liquid into the micropipette tip.
The eject button: It is used to eject the tip of the micropipette without touching it’s. The button is linked to the meter bar, which pushes the micropipette tip off.
Volume adjustment: A circle at the top of the micropipette is rotated to decrease and increase the set volume. The volume intake required is ensured by adjusting the volume with volume adjustment.
Volume window: The volume window displays the adjusted volume. Within the range of that pipette, different liquid values can also be set. A different micropipette allows for a different volume range to be measured.
Pipette barrel: A pipette barrel is a tube that contains air and houses the pipette tip. Pushing the plunger forces a volume of air out of the barrel, and releasing the plunger allows that air to return. The plunger has two stops that are used differently for taking up liquid in forward and reverse pipetting.
Pipette tips: These are attached to a micropipette that are used to take in liquid and then transfer it from one location to another. Different sized tips are used to take in various volumes of liquid.
MICROPIPETTE SIZE AND COLOUR
Tip size and color
0.2 – 2 µ
1 – 10 µ
2 – 20 µ
20 – 100 µ
20 – 200 µ
100 – 1000 µ
1000 – 5000 µ
TYPES OF MICROPIPETTE
Micropipette Classification Based on Working Principle
- Air Displacement Micropipette:
The air displacement principle used by micropipette is made up of a piston that can aspirate and disperse liquid samples while moving an air pocket upwards, downwards, and back. The internal mechanism of the pipette is not in direct contact with liquid or sample. To pull the liquid into and out of the pipette, an irreplaceable pipette tip is used.
- Positive Displacement Micropipette:
The piston in these micropipettes is in direct contact with the sample or material. The disposable tip of a positive displacement micropipette is an extremely small syringe that is made up of a capillary and a piston (which is movable inside) that can directly move liquid.
Micropipettes are classified into two types based on their operating mechanism
- Mechanical Micropipette: A spring piston mechanism is used to operate micropipettes by hand.
- Electronic Micropipette/ Automatic Micropipette/ Digital Micropipette:
Typically, the electronic micropipette is automated and hence can also be called as automatic micropipette or digital micropipette. Single-touch buttons are used for liquid aspiration and dispensing, rather than manually pressing and depressing the plunger. Electronic pipettes frequently allow users to create customized programs for the device, allowing the pipettes to be adapted to various application requirements.
Micropipette classification based on the number of channels
Micropipettes are classified into two types based on the number of channels:
- Single Channel Micropipette: A micropipette with a single channel is the one that can be used to aspirate or disperse the liquid.
- Multi-Channel Micropipette: This type of micropipette has several channels for aspiration or dispersing liquid. The most commonly used multichannel micropipette models are the 12 channel, 8 channel, and 16 channel. When dealing with large quantities of samples, multichannel micropipettes can reduce the work of a single channel micropipette.
Volume/Capacity: Micropipettes are classified into two types based on their volume/capacity.
The amount of liquid to be dissipated or aspirated in a fixed-volume micropipette is fixed. They are used when the same volume of liquid needs to be dispersed several times.
The volume range of the micropipette is limited and maximum. The amount of liquid aspirated and dispensed can be adjusted (within the volume range) to meet the needs of the individual.
Areas to where micropipettes can be used.
Micropipettes are commonly used in microbiology, chemistry, and medical labs to ensure accurate and precise specimen transmission.
The following are the most important fields in which a micropipette can be widely used:
- Wellness and healthcare
- Food and Drink
- Environmental Surveillance
- Institutes of Higher Learning and Research
- Used in kits for Diagnostic testing.
- Widely used in Life Sciences