The hidden role of motion systems in electronic pipetting
ELECTRICAL & ELECTRONICS ERGONOMICS TO ACCURACY
PORTESCAP
The hidden role of motion systems in electronic pipetting
Across laboratories worldwide- from research and development to clinical diagnostics- laboratory professionals rely on pipettes to measure and dispense precise liquid volumes. Even small inconsistencies at this early step can cascade into costly failed assays, repeat testing, or compliance risks, making accuracy and repeatability essential. As a result, air‐displacement micropipettes are often the primary choice in modern testing environments.
Air‐displacement micropipettes became particularly visible during the global response to COVID‐19, where vital RT‐PCR sample preparation required consistent, high‐volume pipetting and expedited the uptake of electronic pipette use. Sample preparation has historically used both manual and electronic pipettes, but as laboratories increasingly prioritize efficiency, consistency and associate comfort, electronic pipettes have become the more popular choice.
Manual vs. electronic pipettes
In an air‐displacement pipette, manual or electric action of a piston drives changes in the air column that ultimately aspirate and dispense liquid. Manual pipettes rely on the operator to compress and release a spring-loaded mechanism, generating the required pressure changes. While effective, this design introduces natural variations in force, speed, and timing, each of which can subtly influence the resulting liquid volume. Repeated manual pipetting also presents ergonomic challenges, as frequent use can lead to discomfort and an increased risk of repetitive strain injuries for the operator.
Electronic pipettes remove much of that burden. Instead of a thumbcontrolled plunger, a digital interface controls a motorized piston via a more user-friendly button. The outcome is more consistent aspiration and dispense profiles based on predictable motion, as well as reduced operator strain.
As an additional design feature, digital interfaces can improve the accuracy of volume settings and monitor output, while automated functions like sequential multi‐dispensing, mixing and tip detection can further reduce the likelihood of human error. The digital interface can even store programs, reducing time for set-up and thus further improving efficiency.
Motor selection for electronic pipettes
As the first step in many laboratory workflows, pipetting performance has a direct impact on downstream results, reproducibility and operational efficiency. For instrument designers, motor selection influences not only motion performance and accuracy, but also calibration stability, maintenance demands, and long term cost of ownership.
Motor choice plays a key role in the precision and accuracy of electronic pipettes by defining the force, speed, smoothness and positional fidelity of the piston’ s movement. The two most common options are brushed DC motors and stepper linear actuators.
54 PECM Issue 83