Techniques for Pipetting Challenging Liquids Application Guide
Some common laboratory reagents can be challenging to pipette, especially those that are viscous, volatile, foaming or oily. With best pipetting practices, however, the challenges can be easily overcome. Accurate pipetting of liquids such as acetonitrile, Tween 20 Triton X-100, protein solutions and oils requires accounting for each liquid’s specific properties.
Commonly Asked Questions
- Why is my pipette leaking, and how can this be avoided? - If you are pipetting volatile liquids like methanol, pre-wet your tip and use reverse pipetting to avoid dripping.
- If your pipette leaks with all liquids:
- Switch to manufacturer-recommended pipette tips
- Clean the tip cone and piston of your pipette and check for wearing
- Use correct technique for attaching tips
- If the above actions do not resolve the issue, send your pipette for repair and maintenance
- Can I cut pipette tips to make pipetting viscous liquids easier? - Never cut pipette tips, as cutting them will devastate the accuracy and precision. Proper pipetting technique - using slow speeds and reverse pipetting - allows reliable pipetting of viscous liquids like Polyethylene glycol (PEG).
- How can air bubbles be avoided while pipetting? - Use reverse pipetting to avoid foam and bubbles while dispensing.
Download this guide to learn the benefits of reverse pipetting for pipetting viscous, volatile or foaming liquids - and how to distinguish whether your pipette and tip combination is leaking or if it is a characteristic of the liquid.
