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Types of Propipettes in the Laboratory

It is an instrument to measure liquids in routine laboratory procedures. This is an essential element for many researchers, whether they are pharmacists, nurses, microbiologists or chemists, or for anyone else who requires the measurement of the desired volume.

The simplest thing in itself cannot quantify the amount of volume; for these cases, as for the well known pears, the analyst must use the glassware called a pipette, which is a graduated sterile glass tube through which the “pipetted” liquid rises. On the other hand, there are propipettes capable of measuring graduated amounts of liquid.

An example are the micro-pipettes, as the one shown in the image above. The number 400 shown on the display indicates the volume measured, allowing the analyst to accurately manage the fluid supply.

Depending on their operation they can be of two types:

Mechanical Type

  • These propipettes are considered mechanical because they work like pumps.
  • They consist of a reddish rubber bulb that expels the air after pressing it with your fingers; when you slowly release your fingers, the liquid rises through the glass.
  • This mechanism is the same as the droppers found in the box of certain medicines, or the famous Pasteur pipette.
  • There are many accessible designs of mechanical propellants, some rudimentary and others modern, that allow a range of precision according to the requirements of the work or laboratory study.

Because propellants go hand in hand with the pipette, the smaller the second one, the more refined and special the first one should be. For this reason, there are propipettes designed exclusively for micropipettes; these contain very small volumes and are expressed in microliter units (μL). The micropipettes are widely used in the field of pharmacy, biochemistry, bioanalysis, among others, these are mechanical type.

Electronic Type

Electronic propipettes allow much more precise measurements than mechanical or manual propipettes. They are made to perform several measurements at the same time, especially in microbiological analysis. They also consist of a digital display on which the amount of pipetted liquid is shown.

Other Types of Propipettes

In addition to those that come in rubber, there are also ones that are ergonomic and designed to be used with one hand.

They have a wheel that can be turned for precise suction handling. These usually have a color that indicates their capacity:

  • Red: 25 ml
  • Green: 10 ml
  • Blue: 6 ml

There are also automatic electric propipettes that have a vacuum and dispensing speed regulator, and have a hydrophobic filter that prevents over-suction.

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