Join Linda the lab manager as she explains some of the best practices when purchasing pipette tips.
In Linda’s lab, her colleagues spend a lot of time with their pipettes, it’s not a task everyone enjoys – however, accurate fluid transfer is critical to the success and reproducibility of their research. Today LINDA is going to teach her new lab members about the importance of purchasing high quality pipette tips.
Why not just buy your pipette tips from the cheapest vendor?
Pipette tips are in integral part of your liquid handling procedure, and using poor quality or ill-fitting tips will significantly impact the performance of even the best pipette. Linda knows to look for premium quality tips from a reputable vendor that are produced from high-quality polypropylene. Tips should be straight, free of moulding flash, and have no visible flaws or imperfections.”
Know your needs
Pipette tips come in a variety of formats and sizes that are appropriate for different applications. Tip types include standard, extended length, filtered and non-filtered, and macrovolume as well as tips designed specifically for automated systems.”
In addition – check that the packaging is both suitable and convenient for your application. Non-sterile tips can be purchased in bulk, racked, and various reload style options. Sterile tips in racked and some reload options. While buying bulk packed tips may be more affordable – consider that somebody will have to manually rack and sterilize them for use.
Beware of additives
Be aware that some chemical additives can potentially contaminate your samples. Metals can be used in dyes for blue or yellow colored tips, and chemicals such as oleamide and DiHEMDA which are added to aid the injection molding process can interfere with results. High quality tips will be marked as being free of these additives.
To minimize error and to ensure accurate results – make sure your pipette tips fit properly. You shouldn’t have to apply excessive force to apply the tip and it should stay in place on the pipette. If the ejector doesn’t work, or there is liquid leaking it may be the wrong tip.
When using air displacement pipettes, all the liquid in the pipette tip is part of the measured volume. Even with very smooth surfaces – standard tips tend to retain small amounts of liquid especially when working with sticky samples like DNA and proteins. For the best performance, look for tips with special low retention qualities. , such as specialty coatings or low retention properties built into the resin of the tip – such tips will further protect your samples from possible coating contamination.
Barrier and Filter Tip
Barrier tips serve two purposes – to protect your pipette from aerosols created when fluids are aspirated into the pipette tip, and to protect the pipette from contamination and/or damage from over-pipetting. This typically happens when you have a pipette that fits multiple tip sizes and select a tip too small for the volume dialed on the pipette. These tips are particularly valuable for sensitive applications such as PCR. High quality tips may also include filters that block or change color if liquid is aspirated into them.
Try before you buy
Before she makes her final decision, Linda knows to request sample pipette tips to make sure they fit the pipettes in her lab, meet her requirements, and the demands of her application.
“Alright team – the new tips have arrived – let’s try them out.”