For a laboratory involved in routine assay development and screening, achieving higher throughput depends on the ability to process multiple batches of assay microplates accurately and swiftly. Hence the need for a microplate management system that provides efficient and less erroneous handling of plates. “We have systems in place for high-throughput primary screening, where you need to process a large number of microplates, as well as for secondary screening, where you are doing a large number of different assays,” says Debra Toburen, senior product manager of integrated systems at Velocity11 (now a part of Agilent Technologies). “You need these systems where you want to automate repeatable tasks and ensure reproducible results.”
Microplate management systems include a variety of robotic instruments that are designed to perform very specific functions, such as microplate handlers, stackers, washers, dispensers and plate readers. Some are designed to perform even more specific functions, such as plate piercing, sealing, barcoding and centrifugation. All these instruments are equipped with the appropriate software programs to help them function seamlessly and accurately
Automated, unattended, reliable operation seems to be what most users demand from their microplate management systems. That is often driven by the constant pressure to drive down the costs per assay while generating better quality data. “It’s the same mantra that has been chanted for years—do it faster, do it better, do it cheaper,” says David M. Donofrio, director of market development at Molecular Devices (now part of MDS Analytical Technologies).
In order to drive down reagent costs, most labs in industry have migrated from screening in a 96-well format to screening in a 384-well format. A few have also moved to an even more miniaturized platform, using 1536-wells. “But 1536-well microplates have been slower to adopt and use because of issues relating to infrastructure, evaporation of liquids and surface tension that are still being worked out,” say Donofrio. There are also challenges working with 1536-well plates for cell culture. Washing cells and performing media exchanges become difficult when dealing with small volumes and well surfaces.
There are a few other considerations when choosing a microplate handling system to run assays that are cell-based, and most of them are dependent on the robustness of the cell. The hardware and software have to be designed to enable manipulations that minimize disturbance to the cell layer and provide a controlled, sterile environment for handling longer incubation times and multiple plate movements. “We have a customer working with stem cell–based assays, and that adds another level of fragility to the cells and [hence] to the assay,” says Toburen.
Most microplate handlers available in the market today are designed to meet standardized plate configurations and enable rapid scale-up to allow automated handling of thousands of samples and plates. Most systems are also very flexible, in that they can accommodate all different types of plates—microplates with and without lids, pipette tip boxes, deep-well microplates and low-profile microplates, and sometimes even vials and tubes. Microplate stackers work in conjunction with the microplate handlers to offer a convenient and reliable solution to stack, store, retrieve and deliver multiple microplates, and most come with options to expand their capabilities. Most equipment providers also have partnerships that allow them to integrate components from other vendors to fulfill the customer’s needs and preferences.
Tanuja Koppal, Ph.D., is a freelance science writer and consultant based in Randolph, N.J.
The BioStack™ Twister® II Microplate Handler is a high-capacity plug-and-play benchtop automation solution for integrating BioTek’s washers, readers and liquid handling systems with expandable microplate capacity, flexibility and intuitive software. The system provides a cost-effective alternative to linear-track and stationary robotic arms. As experimental designs change, additional instruments can be easily integrated with a software “teach wizard” and adaptable setup options. The wizard allows new microplate locations to be taught and ready to use with great accuracy. The compact footprint and removable stacks enable capacity to be expanded or reduced, so the system never takes up more laboratory space than is absolutely necessary.
The BenchCel platform is an integrated benchtop robot and microplate storage solution that delivers the speed and precision of a full-sized automation platform. The platform features a highspeed plate shuttle that accesses integrated microplate stacks and peripheral instruments. This customizable modular design provides the flexibility and scalability required to meet the needs of the most diverse laboratory environments. Features include automated plate delivery for up to four peripheral instruments; ability to handle a range of labware including PCR plates deepwell plates, lidded plates and tip boxes; ability to manage simple to complex applications with the leading automation control software with scheduler; availability in two-, four- or six-stack models for storage of up to 300 microplates.
The PlateStak™ Automated Microplate Handler addresses increased capacity and unattended processing needs by automating handling and storage of microplates and RoboRack™ tip boxes. The system incorporates a bidirectional shuttle that transports plates or tip boxes from cassette to cassette or to programmable locations on the diving board. The diving board extends out from the PlateStak, making plates available on the working decks of most popular instruments. The system is equipped with an onboard controller and multiple sensors that monitor microplate position. It communicates with a host computer via bidirectional RS-232, allowing for a wide variety of commands and enabling easy integration with a variety of liquid handling workstations.