by Caitlin Smith
The impact of using a machine to load your sample into another machine, and then take it out again, is probably bigger than you think. If you were to employ such a machine, the sudden lack of routine work might make you raise your head and consider all of the other things that you could be doing, such as designing more experiments. And the possibility that the machine could be engineered to load many plates sequentially, each with a very tiny sample, means that you can test hypotheses that require large sample sizes, or extensive screening, in short order.
Luckily, these machines do exist in the form of microplate handing devices, such as microplate loaders, robots, and stackers. Kevin Keras, business unit manager for automation, consulting, engineering, and services at Caliper Life Sciences, believes that not all devices are created equal, however. “Plate loaders such as the Caliper Twister II or Hudson PlateCrane were designed for the specific purpose of moving microplates, and their software and tooling are optimized to make this simple and straightforward,” says Keras. “A fair number of industrial robots from other manufacturers have been deployed as well. These robots are generic devices that are appealing due to their industrial strength reputations for robustness, speed, and flexibility. However, in many cases, using an industrial robot to move a microplate is overkill, as payload is a fraction of the robots rated capacity and moving a plate full of reagents at high speed is not always advisable.” He also disavows industrial robots based on the fact that they usually come with complex proprietary operating systems and languages, which are “necessary tools for the vast number of applications they serve in automotive, semiconductor, and other industries,” says Keras, but not necessarily for you. Using them requires a large initial investment of time and effort that you may not want, or need, to expend.
Walk-away automation: how automated is automated?
Virtually all plate loaders and stackers are designed to automate routine tasks so that you don’t have to—but how true is it that they bring “walk-away automation”? Can you set it up to run before going home for the night, or will the machine get stuck because it needs you to enter a value or flip a switch? This will depend on how many plates the devices can load, and also how long it takes to read each plate (which is mainly a function of your experiment, and the speed of the plate reader).
For microplate handing, this is usually expressed in number of plates. Caliper’s Twister II plate loader can handle up to 480 plates, for example, according to Keras: “We now have a new variation of our Twister II plate loader. Twister II is a cylindrical plate loader with storage pods and racks configured in a semi-circular fashion, which is ideal for integrated systems needing extended walk-away time.” Their new product, Twister II Side Loader, is designed to be more of an extension of a liquid handler or reader, and comes with a PC and their iLinkPro scheduling software, along with three storage racks that each handle up to 120 standard microplates. For your biggest, longest jobs, Caliper offers a new plate loader. “AutoSTAX delivers trays of plates directly to the liquid handler deck, which is a great solution for plate replication operations with exceptionally long walk-away time (up to 840 plates),” says Keras.
Another option is the SynchroMax ET microplate handler from Molecular Devices (now part of MDS Analytical Technologies), which provides walk-away automation for ELISA workstations and cell-based screening units, such as SpectraMax readers and AquaMax dispensers and washers. “ELISA and cell-based screening assays make up the largest application segments for life sciences research,” says Andy Boorn, president of MDS Analytical Technologies. “With the SynchroMax ET, researchers can run up to 320 microplates uninterrupted, improving efficiency and freeing up valuable research time.”
Saving time, saving space
Saving time is always a requirement of a microplate handling system, but it’s also a boon to many labs if the device will save space, or at least minimize the instrumentation footprint. One example of this is the StakMax system, a microplate stacker for single instrument automation from Molecular Devices. “The StakMax system's small footprint makes it ideal for tight benchtop environments where automation is required,” says Boorn. “The system can process up to 50 plates per batch and can be integrated with any Molecular Devices' SpectraMax reader sold today, as well as selected older models.”
Caliper also offers plate feeders that will save time and space. “We now support the use of HyperTask HyperSTAX plate feeders in our Sciclone and Zephyr liquid handling products,” says Keras. “HyperSTAX are ‘pez dispenser’ style plate loaders that we use to feed plates directly to the liquid handler deck from below. This improves throughput, saves bench space and can minimize the need for an external plate loader.” Another option that Caliper is finding to be popular for their Staccato Integrated Systems, is their iSTAX plate loaders: “iSTAX are also plate dispensers, except they load plates from the bottom of a stack onto high speed linear rails, which then deliver them to liquid handlers, robots, or Twister II,” says Keras.
Integrating with analysis software and other brands
Some microplate handling devices also include software for analysis, in case you don’t have your own, or you are looking for something new. Boorn says that, “SpectraMax systems are integrated with Molecular Devices' popular SoftMax Pro microplate reader data collection and analysis software, which allows researchers to have access to more than 120 assay protocols with complete data analysis.” SoftMax Pro provides real time results for rapid decision-making during experiments. In addition, SpectraMax readers work with SoftMax Pro GxP to allow researchers to perform data acquisition and analysis in a FDA 21 CFR Part 11
compliant environment, such that the data and users are traceable and all electronic records and signatures are documented. “With other microplate reader systems,” continues Boorn, “the instruments are integrated directly with the robot's software, which lacks the data analysis tools inherent in SoftMax Pro software, such as 5-parameter fitting routines and parallel line analysis, creating a loss in system functionality.”
Adding a microplate handling system to an already automated lab or lab system may be cause for concern, though. Some people, especially those with larger labs, turn to consultants to solve this potentially thorny situation. “There is the larger discussion of how to integrate plate handling technology into fully automated solutions,” says Keras. “For nearly 25 years, Caliper (formerly Zymark) has had a very active systems integration, consulting and services business that can create new automation systems or even help redeploy existing automation assets. This latter situation is becoming a much more frequent scenario due to many recent mergers, acquisitions and site consolidations.”
Caliper and Molecular Devices are also trying to alleviate the hassle of changing your lab set-up by working with other brands of instrumentation in mind. “We have even created standard workcells for common third party instruments, such as the Roche Lightcycler, BD FACSArray, and GE IN Cell Analyzer 1000,” says Keras. “Users of these instruments can just order a single Caliper part number to add walk-away automation.” In the same vein, Molecular Devices has developed partnerships “with all of the key automation companies to offer integration kits for SpectraMax systems and SoftMax Pro software. This out-of-the-box automation solution benefits customers by saving them upfront integration time and resources,” says Boorn.
Keras believes that most of the challenges concerning microplate movement have been addressed by current technology, but that we can still make improvements in the area of complimentary products, such as cell culture flasks and tubes. “I do envision mainstream tools that are now commonplace in other industries starting to migrate into life sciences automation,” he says. “For example, vision systems for process control and quality assurance, ultrasonics for liquid level detecting, and radio frequency identification tags for material tracking are all enabling technologies for life science applications.”
