Pipette

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A pipette or pipet is a laboratory tool commonly used in chemistry, biology and medicine to transport a measured volume of liquid, often as a media dispenser.

Types

Air displacement micropipette

Piston-driven air displacement adjustable micropipette that deliver a measured volume of liquid. Come in several sizes, from 0.1 µl to 1000 µl (1 ml). These pipettes require disposable tips that come in contact with the fluid.

Glass micropipette

Used in microinjections and patch clampings.

Graduated pipettes

Graduated pipettes are a type of macropipette consisting of a long tube with a series of graduations, like those found on a graduated cylinder or burette, to indicate different calibrated volumes.

Ostwald–Folin pipette

A special pipette used in measuring viscous fluid such as whole blood.

Pasteur pipette

Pasteur pipettes are plastic or glass pipettes used to transfer small amounts of liquids, but lack gradations of any kind. The liquid is pipetted using a rubber bulb, which is separate from the pipette body.

Positive displacement pipette

Similar to air displacement pipettes, but the difference being the disposable tip is a plastic microsyringe, composed of a plunger which directly displaces the liquid. Less commonly used and are used to avoid contamination and for volatile or viscous substances at small volumes, such as DNA.

Transfer pipettes

Also called Beral pipettes, they are similar to Pasteur pipettes, but are entirely made of plastic, with the bulb being part of the pipette body.

Volumetric pipettes

Volumetric pipettes, also known as bulb pipettes, consist of a glass tube with a large bulb in the middle, with a single graduation mark above the bulb, being calibrated for a single volume (similar to a volumetric flask). his type of pipette allows the user to measure a volume of solution extremely precisely.

Availability

Can be purchased from lab suppliers.

Pasteur and transfer pipettes can be found in many electronic cigarette stores.

Handling and safety

It's considered a bad lab practice to draw liquid inside the pipette using your mouth suction, even if the liquid/solution is harmless.

See also

References

Relevant Sciencemadness threads