A Guide to Choosing a Pipette Tip

There are an array of pipette tips available in the market and it can become difficult to select an appropriate tip for your application. Not only do you need to find a tip that fits your pipette, you also need to decide on the type of tip and the quality of the tip. We’ve compiled a list of items that will help you choose the right tips for your laboratory.

Firstly, it’s worth mentioning the four most common type of pipette tips that are used in laboratories to provide a base for the latter discussion points.

• Standard Tips – these are your standard pipette tips. You will find, however, that most standard pipette tip users are now moving to low retention tips.
• Low Retention Tips – these tips have an inner surface specially developed to keep sample binding to a minimum. This ensures maximum recovery of the sample resulting in high accuracy.
• Filter Tips – these types of tips are used to protect the pipette from aerosols making their way up into the pipette helping to prevent cross-contamination.
• Gel-Loading Tips – these tips are ideal for use with SDS gels or agarose samples. They are generally longer tips and allow for easy loading of gel electrophoresis samples.

Quality really comes into play when selecting a pipette tip. It doesn’t matter how good your pipette is, without the right pipette tip, you won’t be getting the results you require. Pipette tips vary greatly between manufacturers. Here are a few key areas that should be considered when selecting a tip:

• Material – a good pipette tip will be made from high-quality virgin polypropylene. Beware of plastic and/or metal additives that are commonly found in blue and yellow tips as these additives can contaminate samples. If you are selecting a filtered tip, be sure the filter is made from polyethylene and also free from additives such as cellulose.
• Mould Quality – pipette tips are made by an injection moulding machine. The outcome of the pipette tip is based on the design of the mould and the quality of the polypropylene being injected into the mould
• Contaminant Free – ensure that you only purchase tips that have been certified to be free of RNase, DNase, DNA, Pyrogen, PCR Inhibitors, and ATP. This is even more important if you are performing sensitive microbiological testing.
• Fit/Compatibility – not all pipette tips will fit your pipettor. It is important to ensure that the tip you are considering will fit your pipettors. You shouldn’t have to force the tip onto the pipette, it should grab and stay in place with little to no force required. Most pipette tip brands will have a compatibility chart which will help you to choose an appropriate tip. Most tips, however, should be compatible with almost all the popular brands of pipettors around the world.
• Low Retention – low retention tips are becoming more and more popular in recent years. They are generally regarded as a premium tip and you can expect to pay more for them. When looking at low retention tips, ensure that the tips have no secondary process during manufacturing that can cause compounds leaching from the tip during use such as silicone coating.

Once you have identified a pipette tip that will work best for your application, ensure you request samples from your potential supplier before purchasing in bulk lots. This will just make sure that they meet all of your required needs including checking that they fit your pipettes correctly. It is worth taking the time to choose a suitable tip as it will not only save you money but also ensure maximum accuracy.