Micropipetting
Pipetting Technique
Select the appropriate micropipette size and tips for the volume you wish to dispense.
Set the desired. You can adjust the volume by twisting the friction ring or control button or left or right. On some models the volume adjustment may have a 'lock' to avoid accidentally changing the volume. Often the plunger may need to be lifted slightly to trigger this lock to be released.
Hold the pipette in an upright position and apply light pressure when loading the tip to ensure it is secure. Press down on the plunger to the first stop point.
Immerse the tip only slightly when taking up your sample otherwise liquid will coat the tip and will be transferred along with the volume inside the pipette. However, if your tip is not fully immersed in liquid, there is a risk of drawing up air which will lead to a lower volume being transferred.
Leave the tip in the liquid for a second or two after the plunger has stopped rising to allow time for the liquid to stop moving. Avoid touching the sides of the container and hold the pipette upright rather than at an angle.
Examine the tip before dispensing to check for any air bubbles as this will lead to an inaccurate volume being pipetted. If this is the case, expel the liquid and draw it up again until you are sure no bubbles are present.
Slightly angle the pipette tip against the wall of the container and press down slowly on the plunger expelling the liquid.
Press the plunger down even further to the final stop point (blow out) to ensure all the liquid has been expelled (it can be useful to pipette up and down the final solution, washing the tip of any sample that may be remaining). Be sure to pipette slowly and smoothly.
Examine the tip after dispensing to ensure all the liquid has been expelled.
Remove the tip by pressing down the ejector button.
