I work in a quality control (QC) laboratory, where measurement accuracy and precision is critical, so we take great care of our pipettes. However, not every lab is as demanding – academic labs, for example, often have new and inexperienced researchers who may not know how to properly maintain their pipettes, and even clinical scientists can find their pipette maintenance routines slipping a little. I was reminded of this during a recent conversation I had with a colleague where we ended up talking about pipette horror stories. She insists this is a real story.
This story takes place when my colleague was in graduate school, and she found one of her lab mates waving a Geiger counter at his nose. This was back before all the fluorescent labeling technology was developed and many biochemical experiments were done using P32 or S35. This particular lab mate would often scratch the outside of his nose with a pencil while he was thinking. Unfortunately, he was working in the radioactive hood and absentmindedly used an untipped pipette end to scratch his nose. The good news was that his nose wasn’t radioactive and neither was the end of the pipette. But it’s an excellent reminder that you don’t always know where your pipette has been, and it’s a good idea to do a regular cleaning. It’s also a good idea to keep lab equipment and gloved hands away from your face, but that’s another topic.
This brings me to the hard questions—when was the last time you cleaned your pipettes? Or took them apart and ran them through some preventive maintenance and a check to see if they need recalibration? If you’re like many scientists, it has probably been too long. Who wouldn’t rather run a Western blot, do some cloning, or test that next batch of samples (okay, maybe not) instead of taking care of your pipettes?
But think of the consequences.
For many bench scientists, pipettes are one of the most important tools that are used almost every day, if not every hour. They’re precision instruments that are directly tied to the success of your experiments. When parts get worn or become contaminated, or when the pipette is dropped or mishandled, you can end up with experimental problems stemming from the pipette—things like imprecision, inaccuracy, or unintended additions to your solutions.
Here’s a great example from Biogazelle on how the efficiency of their qPCR reactions suffered due to issues with one of their pipettes. They first noticed a problem when the number of assays failing to meet their quality criteria increased. The problem wasn’t precision—their R2 values still looked good—but accuracy was off. They ran some simulations to understand the effects of inaccuracies in pipetting and found that every percentage of inaccurate pipetting ultimately led to a 10-fold increase in failed assays! While it’s not clear if regular maintenance would have prevented this problem, it may have helped them identify the issue during the check-up instead of through assay failures.
This is exactly what I’ve found during my work in a QC lab—that by keeping to a regular pipette maintenance schedule, I could keep my pipettes working within the specifications I needed, reducing downtime and surprises from failed assays.
So why not invest thirty minutes to an hour at regular intervals, or once you start noticing your pipette trending towards its tolerance limit?
If you’re not sure what to do, you can download our 8 Easy Steps tip sheet—it includes a nice checklist of steps that’s quick and easy. With just a little time and effort put into pipette maintenance, you can keep these critical instruments in the condition needed to generate quality data.
As a Quality Control Technician on the Artel team, Kristi Allen is trained and qualified to comply with the requirements of ISO/IEC 17025. Her responsibilities include final inspection and testing of PCS™ and MVS™ systems and reagents as well as calibration, maintenance, troubleshooting and repair of laboratory equipment. Kristi is also part of a technical team delivering Artel Liquid Handling Service in the real conditions of customers’ labs.