The precision and accuracy of even the best calibrated pipettes can be wiped out if you choose the wrong tip type. Depending on the experiment you're doing, the wrong type of tip can also make your pipette a source of contamination, waste valuable samples or reagents, or even physically harm you in the form of repetitive stress injury (RSI). There are many different types of prompts to choose from. How do you know which pipette is best for your pipette and situation? Never be afraid, that's what we're here for.
1) Choose high quality pipette tips to ensure precision and accuracy
When considering which tip type to choose, the first considerations that come to mind are precision and accuracy. If there is any batch-to-batch or intra-batch variation in pipette tip shape, your pipetting will not be accurate. If the tips do not fit your specific pipette, it may affect the accuracy of the pipette. If the seal between the pipette barrel and the tip is poor, the aspirated air may escape, preventing the correct volume of liquid from being aspirated. Therefore, the final volume dispensed is not infallible. Choosing the right tip for your pipette can be tricky.
Which brings us to this question...
2) Universal or pipette-specific tips?
The best choice for pipettes and applications is to use high-quality general purpose tips. These universal tips can be used with most micropipettes on the market. Universal tips are designed to fit securely and tightly on all pipette barrels whose diameters vary by manufacturer. For example, tips with FlexFit technology are flexible at the proximal end of the tip (i.e. closest to the barrel), which allows them to better accommodate a wider range of pipette types. In Labclinics you can find general tips with all the features discussed below (aerosol barrier, scale, ergonomics, etc.).
3) Filtered and filterless tips, advantages and inconveniences
Barrier or filter tips are designed for different conditions. If you will be pipetting substances that could contaminate the pipette (such as volatile, corrosive, or viscous chemicals), then you will want to consider using barrier tips to protect the pipette and sample.
Filtered tips prevent PCR contamination
Aerosol barrier tips, also known as filter pipette tips, have a filter insert in the proximal portion of the tip. Filter cartridges protect your pipettes from aerosols and suction of volatile or viscous solutions into the barrel, all of which can contaminate and damage the pipette. These tips are usually pre-sterilized and DNase/RNase free. For some of these tips, however, "barrier" is a bit of a misnomer. Only some high-end tips provide a true hermetic barrier. Most filters just slow down the flow of liquid into the pipette. The filter barrier in these tips makes them an option for sensitive applications such as qPCR. Barriers prevent PCR contamination by preventing sample carryover in the pipette, which will give you more reliable results. Also, remember to run your PCR positive and negative controls for sample carryover. Also, the filter tips are great "training wheels" for beginners. Many times, pipette contamination occurs when a new lab member accidentally sucks liquid into the pipette itself. It is much easier and more cost-effective to throw away the tip than to send the whole pipette in for repair, because there is liquid in the piston.
4) Low adsorption tip
No matter which tip you choose, low retention rates are a key feature. Low Retention Tips do exactly what the name suggests - retain low levels of liquid. If you've ever looked at a standard pipette tip, you've probably seen a bit of liquid left behind after dispensing. Low retention tips reduce this from happening because they have a hydrophobic plastic additive that prevents liquids from sticking inside the tip.
5) Ergonomic tip
Performing repetitive tasks, such as pipetting, can damage joints and cause repetitive stress injury (RSI). With this in mind, the company has designed ergonomic tips that require lower insertion and ejection forces, reducing the risk of RSI. That said, this function can all fit in nicely. A tip designed to fit your pipette is, as the name suggests, an ergonomic tip.
