Pipettes are among the most ubiquitous tools in research labs. The trusty pipette is easy to take for granted, but how you use your pipettes day-to-day and how you maintain them over time can make a big difference on your experiments and your hand and wrist health. Let's take a look at some pipetting best practices with this in mind.
Like other repetitive motions, pipetting can cause occupational injuries. Research has shown that performing more than 300 hours of pipetting per year can increase the risk of hand and shoulder injury. Many laboratory workers spend more than 500 hours a year (about 2 hours each work day) pipetting. That makes it critical to adopt ergonomic practices.
Using poor pipetting techniques can also wreak havoc on experiments. Many of the technique problems that can increase strain on the user's hands and arms can also reduce accuracy and reliability. For example, if you press too hard when applying tips, the tips may be slightly crushed, which can cause accuracy issues, and you'll likely need to use more force to eject the tips after use, which can increase hand strain. Or, if you pipette at an awkward angle, you may draw an incorrect volume of liquid and potentially increase your risk for injuries over time.
Understanding pipetting best practices will set you up for success.
Ergonomic Pipetting Techniques
Pipetting without attention to technique can cause thumb, wrist, and shoulder injuries to develop over time. Both repetition and force can contribute to the risk of injury, so reducing the force you apply during pipetting can help.
Occupational health experts recommend these pipetting best practices:
- Slow down. Many people pipette too fast, which can increase strain on your hand and create air bubbles inside the tip or cause liquid to enter the pipette body.
- Use good posture. When sitting, keep your back against your chair, and adjust your chair height to a comfortable position.
- Keep your elbows by your sides while working. Keep your hands below shoulder height, and stay close to your work so you don't have to lean or reach.
- Use a relaxed grip and avoid pipetting with excessive force. Too much force can impact both accuracy and physical strain.
- Avoid using twisting or rotating motions. These motions can strain the wrist.
- Take breaks. A 1–2-minute break every 20 minutes is recommended. Use this time to change your position and stretch your fingers, arms, and shoulders.
- Choose lightweight pipettes that are a good fit for the user's hand. Consider purchasing specially designed, ergonomic pipettes, such as Corning® Lambda™ EliteTouch™ pipettors, that require less force to operate.
Pipette Maintenance and Calibration
Pipettes tend to fail more often than other laboratory equipment, and their performance can invisibly degrade over time. Pipette maintenance plays a critical role in ensuring accurate dispensing and maintaining performance over time.
Mechanical pipettes have complex inner workings, including parts that wear out and should be cleaned, lubricated, checked, or replaced at different intervals. Many manufacturers recommend that the internal seal should be replaced every 12 months.
Pipettes also need to be calibrated regularly. According to the Clinical and Laboratory Standards Institute, pipettes used in clinical work should be calibrated every 3–6 months. For academic labs, calibration should be done once a year or more, depending on how heavily the pipette is used.
Document your pipette calibrations and maintenance tasks, and put regular maintenance on your calendar ahead of time. Planning will help you prevent avoidable problems and inaccuracies, and keeping good records will help you investigate and troubleshoot any accuracy or repeatability issues you may have.
Troubleshooting and Correcting Pipette Problems
Chance events and accidents, such as accidentally drawing a corrosive liquid into the pipette body or sudden breakage of an internal part, need to be corrected immediately so they don't damage the reliability of your laboratory results.
Let's say you notice that liquid slowly drips out of the tip after aspiration. This could be a sign of a poor seal, which can often be fixed by cleaning and lubricating the pipette interior and replacing any worn-out parts, or there may simply be a tip compatibility issue. Keep in mind that smaller leaks and deviations may not be noticeable to the user, so scheduled maintenance and calibration are critical, as well.
Adopting proper pipetting techniques and quickly correcting any problems with your pipettes can significantly enhance the quality of your experiments while preventing pain and injury.
At Corning Life Sciences, we've designed a full range of ergonomic pipettes that aim to reduce stress on the body while maintaining high levels of precision and accuracy. Find calibration instructions, pipetting guides, and more at the Corning resource library.