Take a close look around most laboratories and you will find an old, barely used fixture. No one knows who ordered it or who it belongs to. It is yellowed, dusty, and top heavy, with a small keyboard attached. It’s an electronic pipet.
However, times have changed. Much like the cell phone and other electronic devices, electronic pipets have evolved over time. It is estimated that 95% of researchers use air-displacement pipets. Air displacement pipets can be single or multichannel, manual or electronic. With an increasing focus on efficient, user-friendly, ergonomically safe pipetting systems, the demand for electronic pipets is on the rise. Today, with advancements in liquid handling technology, there are new words to describe electronic pipets, such as simple to use, comfortable, workhorse of the laboratory, productivity booster, hand saver, and invaluable.
Initially, it was sufficient to have single-channel pipets with fixed volumes. As technology developed, so did the need for a pipet with varying volumes and multiple channels. The last 50 years have been full of innovation. New technologies, products, services, and entirely new industries have emerged. The call for advancement in research is louder than ever. Innovation is the creation and transformation of new knowledge into novel products, processes, or services that meet market needs, creating fresh opportunities and becoming a fundamental source of growth. What could once only be accomplished through repetitive motions with single-channel manual pipets can now be performed quickly and easily.
Figure 1 – Chart showing the steps in multichannel pipetting.
First developed in 1951 as a fast, economic, and reliable test method for the identification of the influenza virus, the microplate format replaced test methods involving high-volume test tubes. At that time, no one expected that this plate would serve as a reliable format in screening applications. Based on the established 96-well microplate, throughput screening for miniaturized assays started in 1994–95 with the launch of 384-well microplates. The 384-well microplate quadruples the well density with a well-to-well spacing of 4.5 mm and a total well volume of 120 μL; 384-well plates are in a 16 × 24 format.
Convergence of pipets and microplates
It was not until the development of enzyme linked immunosorbent assay (ELISA) technology that the convergence of microplates and pipets really took effect. At the time, no one imagined that a motor-assisted pipet could provide productivity improvements by adjusting the spacing of the tip cones to make the pipet perform sample transfers between different laboratory consumable formats. These standard lab formats, such as tube racks, multiple density microplates, and horizontal gel boxes, were typically used in conjunction with a traditional single-channel manual pipet.
Figure 2 – Use of an electronic pipet.
Now multichannel electronic pipets are widely used in research, drug discovery, bioassay validation, quality control, and manufacturing processes in the pharmaceutical and biotechnological industries as well as in academic environments. Sample reactions can be assayed in 6- to 1536-well-format microplates. The most common microplate format used in academic research laboratories or clinical diagnostic laboratories is 96-well (8 × 12 matrix) with a typical reaction volume between 100 and 200 μL per well. Higher-density microplates (384- or 1536-well microplates) are typically used for pharmaceutical drug screening applications where throughput (number of samples per day processed) and assay cost per sample become critical parameters, with a typical assay volume between 5 and 50 μL per well.
Minimizing steps with multichannel pipets
Most experimental work starts in individual tubes, for which single-channel pipets are ideal. Once protocols have been established, the next step is to scale up the research and run larger pilot experiments or assay runs, which are often performed in 96-well microtiter plates (see Figure 1). Utilizing single-channel manual pipets at this stage can be extremely time consuming and highly repetitive, and can increase the risk of pipetting errors.
Multichannel pipets were developed for use with microplates. Demands on scientists to produce valuable research, publish papers, and justify funding are high. The pressure to increase productivity is ever growing, while the demands to maintain experimental accuracy and reduce the risks of personal injuries to scientists still remain a priority. These pressures necessitate reliable, easy-to-use laboratory equipment that can improve efficiency, with performance that can be certified. Growth of the drug discovery market and techniques such as serological testing, molecular biology, immunology assays, high-throughput screening, and polymerase chain reaction (PCR) have rapidly expanded the use of microplates. The nature of this work, compounded with the need for increased productivity while maintaining accuracy, precision, reduced pipetting fatigue-related mistakes, and repetitive strain injuries (RSI), has heightened the demand for ergonomic pipets.
Ergonomics can influence data production and well-being. Pipetting is a forceful and repetitive activity, and there is a strong association between pipetting and the occurrence of repetitive motion injuries. Relieving the repetitive strain on the thumb, electronic index-finger trigger action reduces common repetitive stress injuries caused by thumb-driven pipets.
Operator fatigue is an often-overlooked yet crucial component for maximum accuracy and repeatability. Repetitive motions cause stress in hand joints and muscles. Even a well-trained and experienced operator will note a decrease in accuracy and repeatability as the length of pipetting time increases. Electronic pipets allow users to complete their research as quickly and efficiently as possible (Figure 2).
Pipetting with an ergonomically designed single-channel pipet can cause hand fatigue and increased risk of RSI, even with correct pipetting technique. If your hands are tired, errors can be introduced that could have detrimental effects on accuracy and precision. Continuous repetitive pipetting increases the risk of mistakes, such as angling the pipet while aspirating, submerging the tip too far into the liquid, and removing the tip partially while aspirating, all having potential detrimental effects on results. This may result in the need to repeat the assay—increasing consumable, reagent, and labor costs—and ultimately reducing research efficiency.
Today’s fast-paced environments demand that laboratory results be more standardized, require less time for tedious bench procedures, and ensure that pipetting tasks are executed quickly, accurately, and with less risk of developing repetitive strain injuries typically associated with manual pipet use. Understanding the array of liquid handling instruments and options available is the first step toward achieving more reproducible results, optimizing performance for each of the liquid handling steps involved in the workflow, and enabling the highest levels of accuracy and precision to be achieved across all applications.
Paula Heimler is Field Product Manager, Thermo Fisher Scientific, 21 Hickory Dr., Waltham, MA 02451, U.S.A.; e-mail: firstname.lastname@example.org .