Pipetting is a basic skill that medical laboratory professionals must master in order to accurately measure and administer medication and other fluids. Improper pipetting technique can lead to inaccurate dosage, which can have serious consequences for patients. In order to ensure accurate dosages, nurses should follow guidelines for proper pipetting technique.
Some key guidelines for proper pipetting technique include:
Pre-Wet the Pipette’s Tip
The first step in proper pipetting technique is to pre-wet the pipette’s tip. This ensures that the liquid inside adheres to the interior walls of the pipette and prevents air bubbles from entering into your sample.
Pre-wetting should be done by dipping the tip of a new, unused pipette into clean solvent before use. Pre-wetting should also be done if the pipette has been used for more than a couple of hours or has been exposed to extreme temperatures.
Work on a Temperate Equilibrium
Typically, laboratory pipettes work best when they are placed in a temperature-controlled environment, such as a laboratory with regulated room temperature and humidity. This helps to ensure accurate pipetting, as the liquid inside the pipette will not expand or contract due to temperature changes, which can lead to inaccurate measurements.
Check the Tip of the Pipette for Droplets
After each use of a pipette, it is important to inspect its tip for any droplets or residual liquid that could have been left behind. This can help to ensure accuracy and the integrity of your sample measurements. If droplets are present, they should be wiped away with a clean cloth before continuing to work.
Forward or Reverse Pipetting
When using laboratory pipettes, it is important to be mindful of the technique used. Forward pipetting is when the plunger of the pipette is pressed down and liquid is drawn up into the pipette. Reverse pipetting is when the plunger of the pipette is released and liquid is forced out of the tip.
Forward or reverse pipetting is usually done when working with small volumes. Forward pipetting involves first aspirating liquid and then transferring it into another container. Reverse pipetting requires aspirating and then releasing the liquid back into the same container several times until the correct volume is reached. It is important to pause regularly when using a pipette as not doing so can lead to inaccurate results.
Furthermore, it is also good practice to use the same hand for aspirating and releasing liquid from the container. This will reduce any contamination between containers and ensure accuracy in measurements.
Pause Regularly
It is important to pause regularly when pipetting. Pausing allows the liquid to settle in the tip of the pipette so that a more accurate volume can be obtained. When pausing, ensure that you are still holding the plunger down or releasing it as appropriate.
Make Sure To Use The Right Immersion Depth
For pipetting to be accurate, the depth of immersion in the sample needs to be consistent and at the right level. Make sure to use an appropriate plunger position and insert your pipette tip correctly into the sample.
Air aspiration can occur when there is insufficient immersion, especially when using high volume pipettes. Liquid may stick to the outside of the tip if it is immersed too deeply. Aspiration may be limited if the tip makes contact with the bottom of the container.
Following these guidelines will help maintain proper pipetting technique and ensure accuracy in their work. It is important to always practice safe handling of liquids and be aware of the potential risks associated with pipetting. By being mindful of the technique used, nurses can avoid potential errors.
