2) Workflow efficiency:
Leaving out the blow-out makes you working faster when serial dispensing is to be performed. The dispensing mode is naturally the best choice for increasing efficiency.
Good on you when having an Xplorer® or Xplorer® plus
pipette: You can perform the reverse pipetting technique simply by using the rockers – just like you know it from your mechanical pipette:
- Press “rocker down” to move the piston into the lowest position.
- Immerse the tip into the liquid and press “rocker up” to take up the liquid. You have now aspirated the target volume plus the dead liquid volume.
- To dispense the target volume, press “rocker down” once. The blow-out will not be performed before pressing “rocker down” again, and you can…
- Directly aspirate liquid, again.
In case you are processing a workflow being pre-programmed on your electronic pipette, the Xplorer® plus
also offers you the option to include the reverse pipetting into the protocol.
The dispensing mode needs short programming to set the volume of the consecutive dispensing steps. The rest, again, is performed intuitively by the rockers.Tip no. 3: A special type of foaming liquids: Detergents – How to leverage the electronic pipette to accurate transfer of this liquid type
When working with detergents, foaming can be avoided by the recommendations stated above. But detergents tend to foam and pose a second challenge: They create a film inside the tip. A residue that belongs to the dispensed volume is discarded together with your tips! Especially operators in molecular biology experience this in their daily routine since detergents are an ingredient of most master mixes. Thus, there is a need to prepare more reactions than samples to be amplified. Here, pipetting techniques do not help solely. But for these cases, a special type of pipette tips exists. The low retention tips ( epT.I.P.S.® LoRetention
). These tips are ultra-hydrophobic, compensating the lowered surface tension of detergent containing liquids*.
The beneficial effect of the system “electronic pipette with low retention tips” on the reproducibility of results has been widely proven. Find an example from NGS here where this system has been shown to master these challenging tasks and liquids.
The next time you come across challenging liquids, do not get stressed. If no Multipette®/Repeater®
is available, check-in the general overview above how to deal with it and let your electronic pipette solve the problem for you.
Air-cushion pipettes often reach their limits in the wide field of challenging liquids with their different mixtures and concentrations. The best choice for accurate liquid transfer of challenging liquids is the positive displacement system like the Multipette®/Repeater®
. However, there are ways to manage such liquids with air-cushion pipettes. As shown by the example of foaming liquids, the use of electronic pipettes like the Xplorer®/Xplorer® plus
can help avoid the foam creation and thus raise the workflow efficiency and the reproducibility. Additionally, equipped with special pipette tips, this system can give the best molecular biology results like in NGS applications.
* Make sure only to use these tips with detergent containing liquids. Transferring aqueous liquids with these tips can lead to a lower aspirated volume due to the hydrophobic surface. By bigger volumes, the effect is neglectable but should be considered by smaller volumes.