The COVID-19 pandemic has been challenging for many labs, as high demand for SARS-CoV-2 testing has led to ongoing shortages of PCR reagents, pipette tips, supplies, and testing platforms. Pipette tips are an especially critical consumable that are expected to be in short supply for some time while major manufacturers expand production capacity1. Laboratories are searching for alternatives such as different models of tips and different suppliers. Unfortunately, different tips can affect the reliability of your assay results by failing to meet your quality specifications. The need for re-testing adds additional expense and negatively affects productivity. To ensure assay quality when using tips from a different manufacturer, or even a new lot of tips from the same manufacturer, you can measure the accuracy and precision of liquid transfers using the new tips.
While labs can order pipette tips from any manufacturer or supplier, not all pipette tips are created equal. Pipette tips which are poorly designed, or poorly manufactured might not seal tightly to the pipette or pipette head properly, leading to consistently lower volumes of liquid being transferred and potentially jamming up the automated liquid handler or testing platform. Tips are calibrated accurately to deliver exact amounts of liquid and they have to be the right size and shape to not get jammed in the instrument, otherwise you ruin an expensive instrument.”2
Fortunately, you do have options to stay productive, even in the face of pipette tip shortages. By checking the accuracy and precision of liquid transfers performed using alternative pipette tips, you can find out whether they will perform the same before using expensive reagents, which may also be in short supply.
If you need to qualify alternative pipette tips, simply compare the accuracy and precision of liquid transfers using the tips you are considering to the performance of your current tips. One way to qualify tip performance is by utilizing Artel MVS technology. If the MVS data demonstrates that the inaccuracy and coefficient of variation (CV) are similar to what you have been seeing with your current tips, you should be able to use the new tips. One thing to note is, if the pipette tips you are qualifying are from a new manufacturer (as shown in Figure 1), then you will also want to perform a test using your assay to ensure comparability.
Figure 2 shows data from an example study, where we programmed a 384-channel automated liquid handler (ALH) to pipette 1 µL of DMSO and measured how much liquid was transferred when using three different tips—tips specified by the ALH manufacturer (Figure 2, blue column) and two other vendors’ tips. By comparing the relative inaccuracy and CV measurements, you can see that the tips labeled Vendor 2 are probably of sufficient quality to substitute for the specified tips. However, the tips labeled Vendor 3 have a much higher CV, making them a riskier choice.
Getting enough SARS-CoV-2 testing is incredibly important, but challenges abound. It is important to qualify alternative pipette tips and/or a different manufacturer so that you can keep your testing workflows moving even in the face of pipette tip shortages.
Pia Abola is a scientist who walked out of the lab twelve years ago and stumbled into the world of marketing. She never had to look back because it turns out that she’s mostly doing the same things–both her lab work and her marketing work revolve around signaling and information transfer. Chemical, biochemical, behavioral, or digital signals, the math is the same — it’s just scale and medium that differs.