Pipette tips can be used to measure liquid multiple times but once ejected from pipette they should not be reused. To achieve a leakage free seal with the pipette the tip material is slightly elastic. Reattaching the tips might result in reduced accuracy and precision.

It is generally recommended that pipette tips change between different fluids and samples, but for specific fluid properties such as pipetting hot or cold liquids, best results are obtained by changing the tip after each dispensing. To learn more about good pipetting practice, you can sign up for our Pipetting Academy.

Also, if you are interested in more about proper pipetting procedures, cleaning and maintenance of pipettes, read our article Good pipetting practices: How to pipette correctly?

There are multiple types of pipette tips with specific functions:

• standard tips are suitable for most applications
• filtered pipette tips are recommended when sample cross-contamination prevention is critical or when handling dangerous liquids
• low binding or low retention tips are beneficial for viscous and sticky liquids
• extended length pipette tips are intended for reaching samples while avoiding inserting the pipette shaft inside tubes or bottles
• wide bore pipette tips are intended for gentle handling of samples like cells or DNA or when sample contains particulates.

You should use the pipette manufacturers recommended pipette tips to achieve best possible performance. The pipette tips should be picked directly with the pipette from a pipette tip rack by gently pressing and ejected after use directly into a waste container. Never cut, bend or otherwise manipulate the pipette tips as it can affect your pipetting results.

Never cut, bend or otherwise manipulate the pipette tips as it can affect your pipetting results. Sartorius offers wide bore pipette tips when samples contain particulates or if the sample is sticky or viscous choose low retention tips.

Sartorius non-filtered pipette tips can be sterilized in tip trays by autoclaving at 121°C, 1 bar (252°F, 15 p.s.i.) for 20 minutes. You can also purchase ready-to-use sterilized pipette tips. Commercial sterilization is regularly done by irradiation or with ethylene oxide.

Disposable pipette tips are a cost efficient method for measuring reagents and samples. They are easy-to-use and effective in helping prevent contamination.

First determine whether you need sterile pipette tips. In applications where protecting samples from cross contamination is critical consider using filtered pipette tips. Consider the characteristics of the liquids you are working with: for aquous liquids use standard tips and for viscous liquids or when you want to preserve expensive reagents or precious samples use low retention tips.

Choose pipette tips that are recommended by the pipette manufacturer to achieve most reliable and repeatable results. Consider the needs of your pipetting application - What kind of packaging is most convenient for you: sterilized and filtered pipette tips come in single tray packages but in less critical application consider saving plastic and choose one of the refill options. Sartorius refill packages are tested for common contaminants where as refill towers save bench and storage space. Refill tips are an environmentally friendly solution that also help to reduce transportation emissions.

Here is a checklist you can go through to check your pipette and tip compatibility:

• Choose Sartorius pipette tips with Sartorius pipettes (or manufacturer recommended pipette tips)
• Clean your pipette's tip cone and check for dirt
• Check that you are using the correct technique to attach the tip (pick the tip from a tip box, press the pipette down on to the tip, do not rock the tip onto the pipette, do not slam the pipette on to the tip, do not use your hand to twist the tip)
• Check that there is a clear and visible sealing ring between the tip and the pipette
• Perform a quick check if aspirated liquid is leaking
• Do a performance check with your lab balance

If after cleaning and checking your technique the tips are not compatible send your pipette for repair and maintenance in our authorized service.

Low retention pipettes tips are especially advantageous when pipetting solutions with detergents, such as PCR master mixes, enzyme solutions and buffers, and viscous liquids. Low Retention tips have lower residual liquid after dispensing which saves your precious samples and reagents.

Check the lot-specific certificate of analysis. Sartorius purity tested pipette tips are endotoxin-free. Endotoxins are a class of pyrogens. The testing is carried out according to Ph.Eur. 2.6.14 Method D using a chromogenic kinetic method with a detection limit of <0.005 IU/ml (EU/ml). Please see below for additional information on endotoxin free testing.

Sartorius pipette tips are sterilized to SAL 10-6 (sterility assurance level) using electron beam (beta irradiation) in accordance with EN 552 and ISO 11137.

The plastic resin used in manufacturing of pipette tips is tested according to USP661.1 chapter 88 - USP Biological Reactivity tests, In Vivo for a Class VI plastic and according to chapter 87 - Biological Reactivity Tests, in Vitro for polymeric materials.

The raw material also meets the requirements of Ph. Eur. 3.1.3 and 3.1.6.