What is a pipette and how is it used?

There are many types of pipettes (or pipet), but most are essentially a fancier version of a medicine dropper or eye dropper. They are used in a laboratory to transport and/or measure a specific volume of liquid.

Volumetric pipettes allow the user to measure a volume of solution extremely accurately and then add it so something else. They are commonly used to make laboratory solutions from a base stock as well as prepare solutions for titration. They typically only allow you measure one single volume in a particular size pipette (just like with volumetric flasks). Therefore, they come in many different sizes.

There are other types of pipettes also, such as a Pasteur pipette, which is not used to measure the volume of the liquid. It is essentially a large dropper, which can be used to remove liquid from one container and add it to another.

There are also graduated pipettes, also called a Mohr pipette, which also allow you to measure the volume of the liquid in the pipette, although not as accurately as a volumetric pipette. These use a series of marked lines (as on a graduate cylinder) to indicate the different volumes. These also come in a variety of sizes. These are used much like a burette, in that the volume is found by calculating the difference of the liquid level before and after.

All glass pipettes require the use of some kind of additional suction device, typically a pipette bulb (not the Eppendorf pipette or other similar ones, which have a built-in suction mechanism), which is a rubber bulb which sucks the liquid into the pipette and also allows you to drain the pipette in a controlled fashion. A Beral pipette is a one-piece pipette, usually made from flexible soft plastic (polyethylene) that has a built-in bulb on the end.

See the Related Questions and Web Links to the left for pictures and more information on pipets and other laboratory equipment.

First answer by Prosoccer. Last edit by JEK. Contributor trust: 1778 [recommend contributor]. Question popularity: 32 [recommend question]