The Tip of the Iceberg: How Pipette Tips Influence Results

Pipettes are tools widely used in the lab and usually purchased with care. However, as pipette tips are only consumables, they are not usually selected with quality in mind. The standard ISO 8655 requires an extra calibration if pipettes and tips from different manufacturers are used. This study including tips from 15 different manufacturers proves that a pipetting system working perfectly with a certain tip exceeds the permissible error tolerances when a tip from a different manufacturer is used. Furthermore, we found that the calibration method influences the performance of the pipetting system: It is significant whether the calibration is done with or without tip change for each measured volume. Autoclaving impacts the tip dimension as well as the calibration result especially with small volumes. Eppendorf standard tips have been shown to perform within permissible error tolerances regardless of the calibration method or autoclaving. Here, the user is free to choose the method most suitable for his application.