Establishing Good Laboratory Pipetting Practices May Be More Important Than You Realize

The pipette is arguably the tool that gives the scientist the most hands-on contact with their work. Though small, this simple piece of equipment can have a big impact on good laboratory practice (GLP) and good manufacturing practice (GMP). The choice of pipette, how it is used, and its maintenance, can all have a major impact on the reproducibility of experimental protocols. Indeed, as pipetting is commonly the first technique that scientists and technicians learn in the laboratory, it’s important to establish appropriate training, techniques and specifications of pipette use to ensure GMP/GLP compliance.

The latest pipette technologies ensure scientists have access to tools that are both precise and accurate in order to obtain reliable and reproducible datasets. Moreover, manufacturers are increasingly offering more comprehensive service packages to help train scientists with technique guides, tip choices and the latest pipetting systems, as well as maintenance services that ensure pipettes are calibrated and remain within specifications.

This article will highlight how new pipetting systems are helping scientists achieve more reliable and reproducible datasets, and discuss how manufacturers are supporting customers to get the most from pipetting systems.

Why good pipetting practices matter

Along with computers, pipettes can often be the most common equipment type used in the laboratory. On average, personnel spend two hours a day pipetting, which amounts to ~500 hours a year. Scientists process thousands of samples, all of which must be perfectly accurate for the experiments they perform, and therefore depend on pipettes to remain accurate and precise over long periods of time, with minimal maintenance requirements.

Consistency of laboratory practices is a key aspect of GLP/GMP, and experiments should follow the same protocol every time, by every user. This is especially important for assays that are sensitive to protocol changes. Any variability in pipetting can cause experimental errors and inconsistencies that can jeopardize the experiment and the data outputted. Moreover, pipettes can also simplify routine tasks, and speed-up processing of large numbers of samples.

Improving pipetting practices in the laboratory

There are several factors that can determine the accuracy and precision of pipettes in laboratories:

Tools

First, it’s about choosing the best tools for the application, like using air displacement pipettes for aqueous solutions, or a positive displacement pipette for highly viscous and volatile liquids. Variable volume air displacement pipettes are the most widely used laboratory instruments, with utility in multiple applications. Multichannel pipettes are more commonly used in microplate applications, like PCR or cell culture, and dramatically speed up the process of loading multi-well plates with accurate dispenses. Electronic pipettes are ideal for microplate filing, by utilizing multi-dispensing which can further increase efficiency.

Tip choice is also important, and there are different tip designs for every application requirement. Sterile filter tips can be beneficial when the assay is sensitive to cross-contamination, with the filter preventing solution from getting into the pipette. Extended length pipette tips allow users to access the bottom of long test tubes, flasks and deep well plates while reducing the risk of contaminating the pipette. Other specialty tips are also available, such as gel loading tips that speed up loading acrylamide or agarose gels, or low retention tips that have a hydrophobic surface that helps reduce sample loss due to adhesion.

Technique

GLP/GMP relies on consistent and accurate pipetting. The performance of the pipette relies on proper technique by the user. Scientists must use the right pipette for the job, with the right tips, and comply with all GLP protocols to drive reliable, reproducible pipetting without cross-contamination of samples.

High quality guides are available for training users on good pipetting practice, and manufacturers are increasingly offering resources to help users get the most from their pipettes. Essentially, pipette training guides are designed to increase the accuracy and precision of solution dispensing.

Ergonomics

Good technique can be difficult to achieve without proper ergonomics. Poor ergonomic design of pipettes, environment and bad posture can all contribute to health risks to the user, and poor pipetting accuracy and precision over time.

Pipette manufacturers are developing new ergonomically designed pipettes to help users reduce the risk of injury when pipetting. Electronic pipettes, for example, automate aspects like aspirating, dispensing and tip ejection, and multichannel pipettes dramatically reduce pipetting repetition when filling microwell plates.

Maintenance and service packages

Many pipetting manufacturers are providing comprehensive maintenance and service packages that aim to keep the pipette performing at a high level. Periodic pipette maintenance is crucial for GLP/GMP compliance, especially calibration. Calibration is an important aspect of pipette maintenance, and can have a major impact on experimental consistency. With properly calibrated pipettes, scientists can rely on their consistency over months of use. Regular pipette calibration is essential to ensure consistent accuracy during experiments, however, keeping track of calibration intervals for a large number of pipettes can be a daunting task, and it is easy to fall short of frequent recalibration. As such, manufacturers offer custom and standard service packages to bring calibration, preventative maintenance and repair services to facilities.

Cleaning is another major part of these services, with service packages for decontamination, disinfection and sterilization protocols being offered to maintain the lifespan of pipettes and reduce the risk of cross-contamination. They also offer advice on daily pipette care, storage and cleaning to reduce wear and tear between servicing.

Final thoughts

Good pipetting practices are essential for GLP/GMP compliance. More and more, we are seeing manufacturers providing a wide range of services to help laboratories in good pipetting practices. While pipetting is perhaps one of the more basic aspects of laboratory science, the amount of time scientists spend using pipettes, and the dependency placed on them to create accurate and precise data, means that focusing on good pipetting standards can make or break GLP/GMP compliance.

But, more than that, choosing the right pipettes for the job, optimizing techniques to use them, and keeping them serviced over the long-term, can dramatically increase the efficiency of experiment workflows, especially in laboratories that process large volumes of samples.