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2017 Automated Liquid Handling Resource Guide

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2017 Automated Liquid Handling Resource Guide The Lab Manager AUTOMATED LIQUID HANDLING RESOURCE GUIDE What You Need to Know When Buying an Automated Liquid Handling System BY RYAN ACKERMAN Upgrading Stand-Alone Automated Liquid Handling Systems to Workstations BY ANGELO DEPALMA, PhD Small-Volume Liquid Handling Requires Advanced Technology BY MIKE MAY, PhD 20 10 Common Liquid Handling Errors & How to Avoid Them 17 BY LAB MANAGER The Latest in Pipette Tip Design BY ANGELO DEPALMA, PhD Automated Liquid Handling Product Finder BY LAB MANAGER Automatic Liquid Handling Resource Guide 2017 What You Need to Know When Buying an Automated Liquid Handling System Automated liquid handlers come in a seemingly endless variety of configurations, with many different specifications. By Ryan Ackerman MAINTENANCE TIP: AUTOMATED LIQUID HANDLING The signs that you should get your automated liquid handler serviced are fairly obvious. If the system is constantly experiencing glitches or producing inconsistent, unreliable results, it’s probably time to do some maintenance. Mechanical problems are another hint that you may want to call your service technician—these issues can include pipette tips being out of calibration, the deck not being “framed” correctly, belts being worn out, or the pipette stages being out of alignment. Why is it important to know the typical sample How does the sensitivity to contamination affect the type volume being used? of automated liquid handler required? Automated liquid handlers come in a seemingly endless variety of As the instrumentation used to analyze samples becomes more configurations, with many different specifications. An important one sensitive, the methods used to transport and prepare the samples to consider is what minimum, or maximum dispensing volume is must become resistant to contamination to ensure no carryover correct for your processes. If your sample volume is highly variable, occurs. In order to combat contamination, vendors have updated getting a more robust station capable of low-range and high-range systems to use a variety of different materials for sample probes volume dispensing is worth considering. and sample flow areas, along with more proficient rinsing abilities. For low volume samples there are a variety of non-contact options Will process type and downstream analysis affect the which utilize a variety of different methods. type or set-up of automated liquid handler required? With ever-increasing needs for high sample throughput and automation in laboratories, the available options for integrated automated liquid handling systems have increased dramatically. Whether you are looking to automate DNA/RNA preparation, PCR, ELISA tests, next generation sequencing, solid phase extractions, liquid-liquid extractions, or combination systems capable of barcode tracking as well, the possibilities are many in the liquid handling domain. Lab Manager 2017 2 LabManager.com Automatic Liquid Handling Resource Guide 2017 Upgrading Stand-Alone Automated Liquid Handling Systems to Workstations Automated liquid handlers have become indispensable by virtue of freeing operators for other tasks while providing consistency and reproducibility. By Angelo DePalma, PhD or downstream of the liquid handler. Joby Jenkins, global head of liquid handling at TTP Labtech (Melbourn, UK), notes that timing is everything. “Having someone move plates onto and away from the liquid handler is fine if that process is isolated and the worker can go off for an hour or two in between.” But workstations make sense if the dispensing step is rapid and followed by another relatively short step, requiring the worker to keep an eye on operations. Labs in upgrade mode have probably identified process inefficiencies for liquid handlers they already own. Labs in total acquisition mode, for example, those that take on new projects, have the luxury of choosing a ready-built workstation. Many labs today employ automated liquid handlers as stand-alone devices, moving plates manually onto and off the stage to storage, Jenkins advises the latter not to over-specify workstations to incubators, and readers. Integrating liquid handlers with other features accommodate every conceivable anticipated future need. “Defining or functions—that is, turning them into workstations—is attractive, both current and future processes is difficult. If you specify a system but the path to fuller automation can be costly and lengthy. that does everything, it will be large, expensive, and complex. You can simplify the process massively by choosing systems that have the Paul Held, PhD, laboratory manager at BioTek Instruments flexibility to grow with changing business needs. Reducing the initial (Winooski, VT) defines a liquid handling workstation as a investment is attractive to many start-up or smallto- middle-sized multicomponent system, as opposed to “an automated pipettor and businesses.” a computer.” Workstations tend to be modular, consisting of two or more functions (dispensing, aspiration, storage, incubation, shaking, Upgrading, moreover, has simplified compared with even five reading, lidding/unlidding, etc.) and operated in semiautomated or years ago. Software is more flexible, and vendors are designing fully automated fashion. their components specifically for integration and automation. Labs would be better off, Jenkins notes, if instead of over-specifying for Workstations also can be defined based on purpose rather than functionality, they focused on flexibility. This allows for purchasing instrumentation and connectivity, for example, as a setup dedicated exactly what is needed today, with a smooth path toward upgrading to PCR or the same panel of biochemical assays day in and day later. out. But the difference between that definition and the one based on integration, Held says, is “pure semantics.” “The best approach when adding functionality is to deliver a solution that meets your immediate needs but doesn’t limit any future features “The appeal of workstations is that you get an efficient, easy-to-use you may require,” comments Jackson. platform tailored to your methods. The risk of workstations is that usually the simplicity comes at the cost of flexibility,” adds Del Plusses and minuses Jackson, product manager at Hamilton Company (Reno, NV). Both upgrade and “one and done” approaches have advantages and Upgrade considerations disadvantages. Upgrading from a stand-alone dispensing system to a workstation “If you buy everything at the same time, it’s one big purchase order involves adding one or more functionalities occurring upstream and you’re done with it,” Paul Held observes. Labs are assured Lab Manager 2017 3 LabManager.com Automatic Liquid Handling Resource Guide 2017 the pieces will work together, and may enjoy a more harmonious needs. “Workstations differ from devices that execute only one action customer support experience later on. Piecing systems together of a workflow,” he says. “Consider all the steps in your daily routines. requires automation savvy, but affords less experienced labs the luxury For example, is there a DNA extraction before PCR? Do samples of learning how each piece works before investing in the next step. need preparation for mass spectrometry? There are a number of ways to do any of this. Workstations should provide method flexibility.” “Experienced labs with a good grasp of what it takes to automate an assay will generally purchase everything they need to accomplish Before upgrading stand-alone liquid handlers to workstation status, lab that task,” Held adds. They also tend to anticipate better how their managers should identify frequently occurring, repetitive workflow fluid handling tasks will change over time, and purchase integrated operations that might be causing bottlenecks. Failing to take stock in systems—or components—accordingly. this manner often leads to failure, according to Wehrenberg. “Before speaking with a vendor, managers must ask themselves which tasks are Newcomers often fail in their automation goals because they perceive growing, complex, and justify automation. Where would automation the problem to be less intricate than it actually is. “The nuances of allow scientists to work on something else while a workstation takes on automation can overwhelm them,” Held says. what they are doing today?” Labs should always become acquainted with an assay’s manual Automation is not all about throughput and walkaway time. operation before considering automation. Only after breaking an Reproducibility and uniformity are necessary for tasks where assay down to its component parts can a manager decide the level pipetting accuracy is critical. If five people work on the same pipetting and extent of automation required to improve productivity. The task, a robot and automated liquid handler will always be more worst strategy is attempting to automate every operation through one reproducible and consistent. purchase. Regardless of the acquisition path, deploying lab automation Held advises lab managers to “understand their process before intelligently and cost-effectively is difficult for resource-constrained even thinking of automation. Pipette things manually, move plates laboratories. Managers may fret over potential missteps with their first manually, and then incrementally add [automated] liquid handling, and subsequent automation components. Wehrenberg advises these then plate movement. A lab doing an assay with an eight-channel customers to err on the side of flexibility and upgradability rather pipette into a few dozen plates per day learns
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