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Speed, sensitivity, accuracy, and optional modes lead the market
Analyzing many samples quickly and accurately makes up the foundation of much of today’s life science and medical research. Often, much of that work takes place in microplates of various sizes, from 96 wells or more, and sometimes less. To assess a wide range of biological and chemical processes in these plates, scientists often use a microplate reader. The pace of instrument evolution must meet the growing needs of scientists, and that requires instruments with new capabilities.
To find the best new tool for a lab, managers need to know the options. In this instrument class, only a book-length buyer’s guide could completely cover the field. Here, we explore the features of a few new microplate readers. This article gives scientists an idea of the new features available and provides an opportunity to shop more precisely and quickly.
Microplates are used in many kinds of research, including the phytoremediation of diesel-contaminated soils that Brandon Kowalski—a BUILD-funded Biomedical Learning and Student Training (BLaST) trainee at the University of Alaska, Fairbanks (UAF)—is studying here. (Image courtesy of Theresa Vertigan, UAF BLaST laboratory research and teaching technician.)Five modes and more
In October 2017, Molecular Devices (Sunnyvale, CA) unveiled its SpectraMax iD5 Multi-Mode Microplate Reader. This platform includes five modes: absorbance, fluorescence, luminescence, time-resolved fluorescence (TRF), and tunable fluorescence polarization. It also includes automatic filter identification.
If needed, scientists can even add other modes: bottom-read luminescence, TR-FRET (time-resolved fluorescence resonance energy transfer), HTRF (homogeneous time-resolved fluorescence), BRET (bioluminescence resonance energy transfer), dual luciferase reporter assays with injectors, and Western-blot detection.
To analyze the data from this platform, scientists can use Molecular Devices’ SoftMax Pro 7 software. In describing the introduction of this reader, Greg Milosevich, president of Molecular Devices, said that the software extends the company’s “leading data acquisition and analysis solution into regulated laboratories working under GMP, GLP, 21 CFR Part 11, and other similar guidelines for secure electronic records.”
To analyze microplates, scientists often use a reader, such as the PHERAstar FSX multimode plate reader. (Image courtesy of BMG LABTECH.)Shooting for a star
In designing the PHERAstar FSX multimode plate reader, developers at BMG LABTECH (Offenburg, Germany) aimed for speed, precision, and sensitivity. “We designed this plate reader to exactly meet the requirements of today’s screening laboratories,” says Tobias Pusterla, international marketing manager at BMG LABTECH. “This instrument helps to maximize efficiency and increase throughput while minimizing sample expenditure and controlling costs.”
With the PHERAstar FSX, scientists can choose from seven detection modes: AlphaScreen, fluorescence polarization, TRF, TR-FRET, UV/VIS absorbance, fluorescence intensity, and luminescence. This platform also handles various plate formats, up to 3456 wells. Despite working with so many wells, this platform runs fast. “We built this instrument to be the fastest microplate reader,” says Pusterla. “Our customers can always find the best combination of sensitivity and speed by choosing the number of flashes.” In single-flash mode, for example, this device reads a 1536-well plate in just 27 seconds.
Getting that speed requires technology improvements. “One special feature to speed up measurements is the technique of simultaneous dual-emission detection,” Pusterla explains. “In dual emission assays—such as FRET, BRET, or TR-FRET—the reader detects two separate emission wavelengths in one single measurement.” He adds, “This feature makes the instrument super-fast by cutting read times in a half.”
To maintain sensitivity at such speeds, the developers created a new optical design that uses three independent light sources. “One of them is the next-generation laser for TRF/TR-FRET measurements,” Pusterla notes. “This new laser accomplishes up to 60 flashes per second, which increases throughput and the precision of measurement in all plate formats.”
Combining capabilities
Although the capabilities of a microplate reader really change what scientists can achieve, labs depend on technologies working together. In August 2017, BioTek Instruments (Winooski, VT) rolled out its 800 TS Absorbance Reader and the ELx50 Washer. Both of these platforms include color touchscreens to simplify the user interface.
This reader works with plates with 6–384 wells, and provides temperature control and shaking when needed. It also operates with BioTek’s Gen5 Software. The washer works with plates that include 24, 96, and 384 wells. The key is that these platforms work together, which adds automation to a lab.
In describing applications of these devices, BioTek mentions several: ELISA, protein quantification, cytotoxic assays, kinetics, and cell-based assays.
Updates ahead
Many microplate readers can be updated with options as needed. The Spark reader from Tecan (Männedorf, Switzerland) was made for just that need. Even out of the box, this reader provides advanced options. With its patent-pending high-speed monochromator, it takes just five seconds for the Spark to scan a full spectrum. This speed depends in part on the company’s NanoQuant Plate, which Tecan notes was “specifically developed for absorbance-based, small-volume nucleic acid analyses in a multimode reader.” The company points out that this can be used in many applications, including DNA or RNA quantification, nucleic acid–purity assessments, and the determination of labeling efficiency.
In addition, the reader can be set up for fluorescence and luminescence, as well as cell counting, cell imaging, and more. Plus, scientists can use the Spark for incubation and automation. For example, the Spark can disperse reagents in plates with 1–384 wells.
Adding imaging
In some cases, scientists want to analyze and observe samples in a microplate. To do that as efficiently as possible, some platforms combine those capabilities. That’s just what Thermo Fisher Scientific (Waltham, MA) did with its Invitrogen EVOS Cell Imaging Systems, Thermo Scientific High-Content Platforms, and Thermo Scientific Varioskan LUX Multimode Microplate Readers. In describing these platforms, the company points out: “Using the right combination of analysis platforms helps enable experiments that would otherwise be limited by a competing need for instrumentation in your lab.”
With biofilms, for instance, scientists can watch the samples develop with the EVOS FL Auto 2 Imaging System with the EVOS Onstage Incubator. While imaging over days, scientists can also measure the flux of calcium or gene expression with luminescence on the Varioskan LUX Multimode Reader.
This glimpse of today’s microplate readers provides an idea of the technology available, but there’s much more. Many of the manufacturers mentioned here offer complete lines of readers, so it’s possible to find just about any combination of capabilities. The key is finding the options that meet ongoing lab needs, and preferably in a platform that can be updated as needed. At the speed at which this product area moves ahead, scientists can count on advances continuing in what can be done. So, it’s best to get a platform that can move forward with the research objectives in a lab—doing so in fast, efficient, accurate, and sensitive ways.
Mike May is a freelance writer and editor living in Texas. He can be reached at [email protected]