Accurate liquid handling is not the only important consideration during pipetting. Protecting samples and pipettes from contamination is also essential.
This is particularly important in workflows such as PCR and nucleic acid handling, where even a small amount of contamination can affect experimental results.
One option for reducing this risk is the use of filter pipette tips.
Filter tips look similar to standard pipette tips, but they contain a filter inside the tip. However, the presence of a filter does not automatically make them better than standard tips for every experiment.
The important point is to understand the role of filter tips and use them according to the application and the level of contamination risk.
In this article, we explain what filter pipette tips are, how they differ from standard tips, when they should be used, and what to check when selecting them.
What Are Filter Pipette Tips?
Filter pipette tips are pipette tips with a filter installed inside the tip.
The filter is designed to help reduce the risk of liquid or aerosols entering the pipette during aspiration and dispensing.
It is important to understand that the main purpose of the filter is not to filter the sample liquid or remove components from it.
Instead, the filter creates a physical barrier between the sample and the pipette. This can help protect the inside of the pipette from contamination and reduce the risk of contaminants being carried over to subsequent samples.
If liquid or aerosols enter the pipette shaft, they may remain inside the instrument and become a potential source of contamination during later work.
Filter tips are one practical option for reducing this risk.
How Are Filter Tips Different from Standard Pipette Tips?
The main difference between a standard pipette tip and a filter pipette tip is the presence of a filter inside the tip.
Standard tips are widely used for general liquid handling and for applications in which the potential impact of contamination is relatively low.
Filter tips are intended for situations in which it is particularly important to reduce the risk of liquid or aerosols entering the pipette.
This does not mean that filter tips are always superior to standard tips.
Using filter tips for procedures in which standard tips are sufficient may increase consumable costs. On the other hand, using standard tips in contamination-sensitive workflows may create concerns about experimental results or the cleanliness of the pipette interior.
The appropriate choice depends on the workflow, sample type, and laboratory requirements.
When Should You Use Filter Pipette Tips?
Filter tips are commonly used for contamination-sensitive experiments and procedures in which protecting the inside of the pipette is especially important.
The following are some typical examples.
PCR and qPCR
In PCR and qPCR workflows, even a small amount of unwanted nucleic acid can lead to unintended amplification or affect the interpretation of results.
Filter tips may help reduce the risk of previously handled samples or amplification products entering the pipette and being carried over into later procedures.
They are often considered for contamination-sensitive steps such as reagent preparation and template addition.
Laboratories should define in advance which steps require filter tips rather than leaving the decision to each individual operator.
DNA and RNA Handling
Unwanted nucleic acid from another sample can also cause problems in DNA and RNA workflows.
A filter tip provides a physical barrier between the sample and the pipette, helping to reduce the risk of contaminating the pipette interior.
However, filter tips alone cannot prevent every type of nucleic acid contamination.
They should be combined with other appropriate practices, such as separating work areas, managing equipment correctly, changing tips between samples, and replacing gloves when necessary.
Infectious or Potentially Hazardous Samples
Filter tips may also be selected when handling infectious samples or liquids that require additional care.
Reducing the risk of liquid or aerosols entering the pipette can help protect the instrument and may reduce the burden of cleaning and maintenance after use.
The required precautions will vary depending on the sample and the safety rules of the facility.
Filter tips alone do not ensure safe handling. Researchers must always follow their laboratory’s approved procedures and safety requirements.
Procedures That May Generate Aerosols
Fine droplets or aerosols may be generated when liquid is aspirated or dispensed too quickly, or when bubbles form inside the tip.
Correct pipetting technique should always be the first line of prevention. However, in workflows where aerosol-related contamination could have a significant impact, filter tips may provide an additional layer of protection.
When You Want to Protect the Pipette Interior
Filter tips may also be used to help keep the inside of the pipette clean.
If liquid enters the pipette, the instrument may require disassembly, cleaning, inspection, or maintenance.
Using filter tips for appropriate samples and procedures can help reduce the risk of internal contamination.
Do You Need Filter Tips for Every Application?
Filter tips are useful for contamination control, but they are not necessarily required for every pipetting procedure.
For general liquid transfer or work in which contamination would have a relatively limited impact, standard tips may be sufficient.
When deciding whether to use filter tips, consider the following:
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The potential impact of contamination on the experiment
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The type of sample being handled
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The consequences of liquid entering the pipette
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Laboratory procedures and internal requirements
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Consumable usage and cost
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Whether standard and filter tips can be assigned to different workflows
Some laboratories may choose to use filter tips for all applications. However, this can have a significant cost impact in laboratories with high tip consumption.
Another practical approach is to use filter tips for sensitive procedures such as PCR and nucleic acid handling, while using standard tips for general liquid-handling tasks.
The important point is to establish and share clear rules so that the choice of tip does not vary between operators.
What Should You Check When Choosing Filter Tips?
A filter alone is not enough to determine whether a tip is suitable for a particular experiment.
The tip must also match the pipette, volume range, and application requirements.
Volume Range
Choose a tip designed for the required dispensing volume.
Using a tip that is unnecessarily large, or operating outside the recommended volume range, may affect handling and dispensing performance.
Check both the pipette’s operating range and the specified capacity of the tip.
Pipette Compatibility
If a tip does not fit the pipette correctly, it may not create a sufficient seal. This can affect aspiration and dispensing volumes.
A tip that detaches easily, requires excessive force to attach, or allows liquid leakage may not be suitable for the pipette.
Review product information and compatibility guides before selecting a tip.
Sterile or Non-Sterile
Filtered and sterile do not mean the same thing.
Some filter tips are supplied non-sterile. Likewise, some sterile tips do not contain a filter.
For procedures that require aseptic handling, confirm sterility separately from the presence of a filter.
Quality Specifications
Depending on the application, laboratories may require information concerning DNase, RNase, endotoxins, or other quality-related specifications.
A sterile label alone does not necessarily confirm that every application-specific requirement has been met.
Researchers and procurement personnel should share the required specifications and review the available product information before making a selection.
Packaging Format
Filter tips are available in a variety of packaging formats, including racks, refill systems, and bags.
The appropriate format depends on the location of use, frequency of use, storage conditions, and whether manual refilling is required.
For contamination-sensitive workflows, it is also useful to consider how often the tips will be handled and how opened products will be stored.
Filter Tips Cannot Prevent Every Type of Contamination
Filter tips can help reduce the risk of liquid or aerosols entering the pipette.
However, using filter tips does not completely eliminate the possibility of contamination.
For example, contamination may still occur if the same tip is used for multiple samples or if contaminated gloves touch a tip rack or sample tube.
The workbench, exterior of the pipette, tubes, reagents, gloves, and other surfaces may also become contamination routes.
Effective contamination control should therefore include basic practices such as:
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Changing tips between samples
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Changing gloves when appropriate
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Maintaining a clean working area
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Separating work areas when necessary
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Cleaning and inspecting pipettes properly
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Standardizing consumable storage practices
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Using appropriate pipetting techniques
Filter tips are most effective when used as part of a broader contamination-control strategy.
Choose Between Standard and Filter Tips Based on the Application
Filter pipette tips create a physical barrier between the sample and the pipette, helping to reduce the risk of liquid or aerosols contaminating the inside of the instrument.
They can be a useful option for contamination-sensitive workflows such as PCR, DNA and RNA handling, and the handling of potentially infectious samples.
However, filter tips are not required for every procedure.
Laboratories should understand the differences between standard and filter tips and select the appropriate type based on the experiment, sample, internal procedures, and cost considerations.
When choosing a product, it is also important to check more than the presence of a filter. Volume range, pipette compatibility, sterility, quality specifications, and packaging format should all be considered.
WATSON offers both standard and filter pipette tips for a variety of laboratory applications.
By reviewing factors such as volume, sterility, and pipette compatibility, laboratories can select tips that better match the requirements of each experimental workflow.