In the field of laboratory work, the cleanliness of equipment is critical to achieving correct and effective results. Filter and other pipette tips are used in many scientific fields, including molecular biology and chemistry. The following tips will help you avoid contamination and ensure the samples and the pipette are safe from aerosols and liquids. A common inquiry that is asked in laboratories is if filter pipette tips can be autoclaved, which is a procedure that involves the use of high-pressure steam to sterilize tools.
This article further explains the details of filter tips, autoclaving, and the points to bear in mind when autoclaving these crucial lab accessories.
Filtered pipettes contain a hydrophobic filter inside. This filter is a barrier that minimizes the chances of aerosols, liquids, and contaminants getting into the pipette shaft while pipetting. The filter prevents pipette contamination, especially when using biological fluids, toxic chemicals, nucleic acids, proteins, or infectious agents. PCR, cell culture work, and microbiology are some areas where filter pipette tips are applied due to their capability of preventing cross-contamination.
A pipette tip contains a filter with several uses, as explained below: It protects the pipette from sample contamination, which may be detrimental when using small volumes of prone-to-contamination liquid. It also shields the sample from contamination from aerosols or particles on the pipette, keeping the sample integrity intact during the experiment.
Furthermore, the filter assists in avoiding the contamination of liquid with other materials, which may occur due to imperfect pipetting, foaming liquid, or any other reason. This protection is beneficial when using dangerous or contagious substances since it avoids the contamination of the pipette and other samples.
Autoclaving is sterilization that uses steam pressure to eliminate bacteria, viruses, fungi, and spores. The traditional autoclaving procedure exposes equipment to the heat of approximately 121 degrees Celsius (250 degrees Fahrenheit) and pressure of 15-20 psi for a certain period, usually 15-30 minutes, depending on the load and type of items being sterilized. Autoclaving is common in laboratories, hospitals, and industries to sterilize any item that needs to be free from contaminants.
Autoclaving is also very effective because high pressure and high temperature inactivate proteins and destroy the cell membranes of all microorganisms in the solutions. It is regarded as one of the most effective ways of sterilization and is applied to objects exposed to high temperatures and moisture.
However, not all items taken to the laboratory can be autoclaved, and this information is usually indicated on the items. Autoclaving is appropriate for heat-resistant articles, such as glassware, metal instruments, and specific types of plastics. Nevertheless, items sensitive to heat or can be affected by moisture, such as plastics, electronic parts, and some chemicals, should not be autoclaved. When loading autoclaves, one should check with the manufacturer of any equipment or consumables to see if they can go through the process.
Filter pipette tips are mainly manufactured from polypropylene, a plastic resistant to heat and chemicals. Polypropylene is often used in laboratory equipment because it is heat and pressure-resistant, non-reactive, and does not melt or distort when exposed to the extreme heat and pressure of autoclaving. However, the filter inside the tip is usually constructed from a different material, for example, polyethylene or PTFE (polytetrafluoroethylene), which can have different thermal characteristics.
Filter media is made to be hydrophilic; it does not allow any liquid, water, or other to pass through the filter. This property is crucial for the filter’s performance but makes it less robust, especially under conditions such as autoclaving.
It is advisable to check with the manufacturer before autoclaving filter pipette tips because it may affect the efficiency of the pipettes. Every manufacturer of filter tip has general instructions concerning the autoclavability of their tips and, if the tips can be autoclaved, the conditions of this process. Autoclavable filter tips and non-autoclavable filter pipette tips are available in the market, and using an autoclave on the non-autoclavable filter tips can harm the filters and the tips.
However, certain risks are involved when the manufacturer says filter pipette tips can be autoclaved. Autoclaving at high temperatures and pressure can lead to filter deterioration, loss of hydrophobicity, or distortion. This can put the filter at risk of compromising the filtration process; hence, the pipettes are compromised.
Further, the autoclaving process is likely to affect the plastic of the tips either through warping or the formation of a brittle material, especially when the tips are autoclaved several times. This results in poor fitment on the pipette, possible leakage during pipetting, and contamination of samples.
Filter pipette tips are among the most useful laboratory tools; however, their use may sometimes present challenges.
Pre-sterilized disposable filter tips are one of the most effective ways to ensure the tips are sterility-free. These tips are made clean and packed separately to avoid mix-ups during storage and usage. Since you can have pre-sterilized tips, there is no worry of damaging them through autoclaving; hence, they are sterile for use.
These tips are handy in experiments that require minimal contamination, such as PCR, cell culturing, and microbiology. They offer confidence that the tips are clean, free from contaminants, and that the samples are safe.
Filter pipette tips should also be handled and stored to ensure that they do not get contaminated. Tips should be packed in their respective packs and only be used once needed; the tips should not be handled with bare hands or the tips exposed to contamination. If tips are stored in bulk containers, they should be closed whenever they are not in use, and tips should be taken using a sterile forceps tip loader to avoid contamination.
To sum up, the possibility of autoclaving filter pipette tip is defined by the kind of tip and filter material and by the producer's information. Although autoclaving is an efficient way of sterilizing many laboratory products, including standard tips, the process threatens the structure and functionality of filter tips. To maintain sterility and pipetting accuracy, it is crucial to adhere to proper guidelines, check with manufacturers, utilize autoclave-safe racks, and explore other modes of sterilization methods when necessary.
Some filter pipette tips may not be autoclavable and, therefore, should be treated with caution. One must always refer to the manufacturer’s instructions to check if the particular tips can be autoclaved and whether autoclaving will affect their performance.
An inappropriate autoclaving may damage the filter or distort the tip, which may cause contamination or lead to inaccurate measurements in pipetting.
Yes, there are. For instance, one can use pre-sterilized disposable tips or opt for UV sterilization. These methods can also help preserve the sterility of the materials without the dangers linked with autoclaving.
