Pipetting Accuracy: Like Holding a Concert in Your Hand
What Does the Symphony Have to Do with Pipetting?
While one might not naturally associate laboratory scientists with symphony conductors, they, like conductors, do rely on a similar arrangement of finely tuned and integrated instruments, skills and techniques to achieve high pipetting performance and reliable test results.
Late in 2011, a quiet crowd sat in rich silence as the New York’s Philharmonic finished its concert with the soft slow notes of Mozart - until a cellphone in the front row began to ring. And ring. People looked around, hoping the phone could be located and quickly stopped. Finally, realizing the piece was ruined for the entire audience, the conductor stopped the performance completely. After the cellphone owner was located and their phone shut off, the orchestra began the piece again and delivered the experience the audience had paid for.
One Small Disturbance Can Affect the Whole Outcome
Pipetting requires a “system” of contributors, working in perfect harmony to deliver optimal measurement accuracy and precision. These system components - validated pipettes and pipette tips, sound measurement technique and user skill, a well-controlled environment and a validated process - are each relied upon to obtain reproducible and predictable test results. For the finest concert performances, the ability and technique of the conductor, the skill and consistency of rehearsed musicians, quality instruments, the composition and arrangement of the music, and the perfect acoustics of a concert hall are essential. Similarly, the bench scientist must ensure a perfectly harmonious pipetting system is established to obtain reliable and consistent test results. A weakness of any one component can affect testing and lead to costly rework, reagent waste, and delays.
When experiments go awry, pipettes are often blamed. However, they may not be the “ringing cellphone.” Poorly performing pipettes, tips, scientists, or processes can also affect results. Even a mismatch of pipette type and liquid can create pipette errors. For consistently repeatable results at the bench, a scientist must be able to trust each component of the entire pipette system. Ensuring the performance of these components ahead of testing is the best way to assure measurement integrity and accurate results.
1. Pipette: Some labs, in order to save money, purchase low-cost pipettes made from inexpensive materials that deteriorate quickly. Purchasing low-quality pipettes can often lead to performance out of tolerance issues between service intervals and costly inaccuracies. Older pipette designs can lead to repetitive strain injuries, which are costly occupational health hazards for any lab. Choosing a pipette that provides performance, reliability and comfort should be part of every pipette system and minimize costs in the long run. Maintaining your investment wisely should include the quality and expertise of an ISO8655 compliant calibration laboratory.
2. Pipette Tip: The term “Universal-Fit ” pipette tip is intended to leads scientists to believe that there is one tip for all pipette brands. This is simply not the case and is a misleading claim. In fact, all pipette tips are manufactured independently and fit each pipette at varying sealing points.
Even if only a slight variation, these sealing point differences can result in performance variations, unbeknown to the user. If you are not using the same brand of tip as your pipette, you should consult a pipette expert to verify your tip of choice for your pipettes.
3. Pipetting Technique: Using a pipette correctly to deliver accurate and reproducible measurements is a skill so often assumed of an educated scientist that lab managers may overlook the need for regular pipette training to assess individual measurement performance.
But just look around your lab, and you’ll see that pipetting techniques vary by user. It is reported that 60-70% of pipetting errors are attributed to the user. Regular pipette training from a qualified provider is essential to maintaining pipette performance, much like musicians must train and practice before their performance.
4. ISO 8655 Calibration: Just as the concert conductor establishes the quality standard of the performance, your pipette service provider has industry standards as well. While ISO 17025 accreditation validates a provider’s documented procedures, only ISO 8655 standards verify the integrity of the provider’s calibration methods and data. There are even ISO 17025 accredited providers who calibrate pipettes in their client’s lunch room! In the lunch room or even in the client’s lab is not the standard - and certainly not the ISO 8655 calibration with a comprehensive repair and pm service - your work deserves.
5. Liquid Properties: Pipettes come in different designs to provide the best measurement accuracy for a particular liquid‘s characteristics. Air displacement pipettes, for example, are not always the best choice for every liquid or application. Contact a pipette expert to demo the best pipettes for your science.
You may not be playing in a symphony on stage, but each part of your liquid handling system must be in place to provide a reliable and repeatable outcome. That’s what you call beautiful music.