Choosing the correct pipette tip is significant to achieve the required accuracy and precision in laboratory activities. Pipette tips are one of the most critical expendables that come into contact with your samples and affect your experiments regarding sample quality and accuracy. This is especially true since many kinds of pipette tips are available today, and it is difficult to select the right one. Here, you will learn what aspects should be considered the most crucial ones while choosing the right pipette tips.
Standard pipette tips can be characterized as the ones most often applied in laboratories. They are general utility types of fittings employed for moving fluids in different processes.
A barrier is present on filtered pipette tips, and it can be polyethylene that shields the pipette shaft from aerosols and liquids. These tips are more important when sterility is required, for example, when handling easily deformed samples like RNA or where contamination is a big issue.
Low-retention pipette tips are designed to alter the tip's surface to reduce the surface tension between the liquid and the pipette tip so that even sticky liquids are fully transferred without any traces. These tips are especially relevant in dealing with precious or small-volume samples, such as in enzyme activity assays or nucleic acid concentration assays, where even slight changes in volume can significantly affect the results.
The sterile pipette tips are packed in packs that have already been autoclaved, and each tip is packed individually. They are useful in any case when one operates in a sterile environment or is to work with sterile samples. Sterile tips are used in cell culture, microbiological, and clinical diagnostic studies.
The following are some of the factors that should be taken into consideration while choosing a pipette tip;
Pipette tips are available in various categories on the market, and each category is designed to dispense a particular volume of liquid. The pipetted volume should range with the volume capacity of the tip used in the pipette. For example, if you use a 1000 µL pipette, ensure that the tip you are using to dispense the liquid will be able to hold the volume without dripping or becoming less accurate. If the tip is very large or very small, then the measurements will not be very precise.
The vast majority of tips are made from polypropylene, which is a chemically resistant plastic and is fairly durable as well. However, the manufacturing process may differ, and it impacts the tip’s clarity, flexibility, and strength. The tips are refined so that they are plain to reduce the chances of liquids being retained on the tips, which improves the tip's consistency.
Filter tip or non-filter tips are used depending on the application you use. These tips are used when handling flammable, toxic, or otherwise delicate samples so that the samples do not come into contact with the flame or other heat sources. They assist in preventing aerosols from coming into contact with the pipette and protect the sample from the different samples. Non-filter tips are appropriate for normal use in the laboratory where contamination is not expected to occur.
Low retention tips are especially critical when working with large samples or small amounts of samples. They ensure all the liquid is delivered, minimizing sample loss and increasing accuracy. If you work with substances like proteins, gels, or concentrated solutions frequently, it will be helpful to use low-retention tips.
However, even if a proper pipette tip is used, the best practices should be followed to achieve accurate and reproducible results. Here are some tips to help you get the most out of your pipette tips:
It is necessary to clean pipette tips before use, especially when using small volumes or solutions that tend to stick to the walls of the pipette to enhance accuracy. If you aspirate and dispense the liquid a few times before the final draw, you coat the tip inside, minimizing retention.
It is best to be as precise as possible with the pipetting, and it is ideal to be as repetitive as possible. Pipette the liquid gently with the tip of the pipette held vertically, immerse in the liquid, and never apply much force. This is achieved when, in the process, you are consistent with the technique that you use.
Calibration and Maintenance Should Be Carried out regularly. It is also important to check that the pipettes dispense the right volume; therefore, pipettes should be calibrated occasionally. No matter the type of pipette tip one uses, if it is well calibrated, it will give correct volumes. This is especially important to avoid contamination and wear of the pipettes, as the manufacturer recommends cleaning and maintaining the pipettes properly.
The pipette tips should be used once because if they are used severally, they are likely to contaminate, affecting the results. It is advisable to use a fresh tip for each sample to avoid having the samples contaminated in any way.
Selecting the right pipette tip is one of the most important laboratory sample analysis processes. It is thus possible to choose the correct tip for the pipette according to compatibility, volume, material, sterility, and application. Also, remember that correct pipetting skills, periodic checks, and adherence to the norms are crucial for obtaining accurate and reproducible results. This means that the kind of pipette tips used will determine the outcome to be expected, whether you are in a normal environment or a sensitive experiment.
As such, the compatibility with the pipette, the volume range, and the application of use are the critical parameters to consider.
No, it is advised to use a fresh pipette tip for every sample to avoid contaminating it.
Filtered tips should be used when the samples are sensitive or are to be used sterilely, while standard tips are enough for general laboratory use.
