Instruments for measuring volume
Measuring liquids…is getting more and more precise!
Miniaturization of the samples to be analyzed has led to the manufacture of precision tools to sample smaller and smaller volumes of liquid.
Discover different types of tools manufactured to respond to the needs of researchers.
In the past, it was common practice to use the mouth to pipet liquids, as we see Dr Frappier doing in this sequence. Today, this practice has been banned in all laboratories because of its associated health risks.
The rubber pipette filler, such as the one that appears on the photograph, is very useful in the laboratory. It is fitted on to the end of a pipette, a graduated glass tube used to measure varying volumes of liquid, and is used to draw up the liquid safely. Pressing the pipette filler expels the air it contains. When it is released, the air present in the pipette rises pulling the liquid along with it.
The pipette pump that appears in this photograph was very useful in the laboratory before the arrival of the automatic pipetter. Fitted on to the end of a pipette, it was used to draw up the liquid safely. The thumb wheel on the side of the pump activated a piston that would rise, and in doing so it created a suction effect on the liquid, which would also rise.
The automatic pipetter is an electrical system used to draw up and release volumes from 1 to 100 milliliters. Powered by a rechargeable battery, the bi-directional pump is controlled by two buttons, one to draw up the solution and the other to release it from the pipette.
The micropipette is used to sample, with great precision, volumes from 0.5 to 5,000 microliters. Its functioning is based on the action of a piston that draws up or releases volumes of air corresponding to the volume of liquid we wish to collect. The volume is controlled with a thumb wheel.
Disposable tips that are adapted to the micropipette according to the chosen volume can be used to sample different solutions without changing the micropipette. These tips must be as thin as possible, most notably for small volumes, to ensure greater precision.