MICROPIPETTES
Equipment Description
The micropipette is a laboratory instrument used to absorb and transfer small volumes of liquids and allow their handling in the different scientific techniques.
The volumes that can be captured by these instruments vary depending on the model: the most common, called p20, p200 and p1000, admit a maximum of 20, 200 and 1000 μl, respectively.
It is noteworthy that the use of micropipettes allows the use of different liquids without having to wash the device: for this purpose, disposable plastic tips are used, which are usually sterile. There are several types of tips: for example, yellow ones for pipetting small volumes (for example, 10 μl), and blue ones for pipetting large volumes (for example, 800 μl).
Types
There are manual micropipettes, in which the volume to be aspirated is set by turning a button on the upper part that is connected to an analog volume confirmation system, and automatic ones, in which said system is digital.
There are simple micropipettes, which only hold one tip at a time, and multi-channel micropipettes, which allow the incorporation of multiple tips (for example, eight), absorbing the same volume in all of them.
Two of the best brands out there are easily recognized on the market today: Eppendorf and Nichiryo.
Equipment Operation
Pipetting technique for clear liquids:
a. The top button is pressed gently to the first stop.
b. The tip is immersed in the solution that needs to be pipetted, making sure that the tip is well placed and that there is no type of residue between the tip and the body of the pipette.
c. Hold the pipet vertically while taking up the solution.
d. To discard the tip solution press the button to the second stop.
and. Discard the tips using the ejector that comes with the pipettes.
Pipetting technique for liquids with high viscosity:
a. Press the top button to the second stop.
b. Immerse the tip in the solution (2-3 mm) and release the button slowly. The tip has to be well filled.
c. Discard the liquid from the tip by gently pressing the top button to the first stop.
Equipment Care and Maintenance
a. Start the day by cleaning the outside of the pipettes from dust or dirt.
b. Use only 70% ethanol for pipette cleaning. Other type of solvent is not recommended.
c. Use the appropriate tips for the pipettes and the amount of solution to be measured.
d. The piston and barrel can be checked twice a year if the pipette is used daily.
Preventive maintenance of the pipette must be carried out by specialized maintenance personnel.