Pipette tip selection
There are a lot of considerations to take into account when selecting a suitable pipette tip for your pipettes.
You can choose from manufacturer supplied tips or generic tips suppliers, with tips ranging in price depending on the material and quality. Other considerations include sterile tips, filter tips, bulk bagged tips or boxed tips.
Manufacturer tips are suggested as the best fit for the pipette that it is designed for. These should provide a good airtight seal and give the best pipetting results, however, the downside of manufacturer specific tips is that if you have a range of pipettes from different manufacturers and of different models then you will need to stock a large number of different tips.
Generic tip suppliers can offer a good compromise, you can purchase tips to fit the whole range of pipettes you own from one supplier, however, this is where cost comes into play, and as with any product you buy, you will need to evaluate the cost against the performance of the pipetting results.
European Instruments always advise that pipettes should be calibrated with the tip that will be used by the end user. This will ensure the results you receive are relevant to the complete pipetting system you are using. If you change your pipette tips between calibrations, then we advise a re-calibration to ensure correct performance is maintained.
If buying from the manufacturer then the tip will be designed to work with your pipette. When using a generic tip supplier you should consider the following:
- The profile of the tip should match the profile of the nose cone. For example, an Eppendorf nose cone has a more parallel design, a Gilson pipette has a tapered nose cone. Trying to use a Gilson tip on an Eppendorf pipette and vice versa can lead to an inconsistent seal.
- Does the tip have enough volume? It is possible a tip will sit further up the nose cone on one pipette than another, this will reduce the available volume running the risk of the aspirated volume touching the end of the pipette, this will cause erratic pipetting results and risk cross contamination between pipetting’s.
- If you require the use of Filter tips, there needs to be a small gap between the filter and the bottom of the nose cone. Any contact may cause an inconsistent seal.
FYI:
Pipette tips should only be used for a single series of pipetting’s, the process of inserting a tip onto a pipette will stretch the plastic tip slightly to get a good seal, this will mean if it is then removed and used again the seal may be compromised!
