Some of the latest developments advancing scientific research
With 2021 now well underway, we felt it might be timely to highlight some of the newer technologies available to enhance laboratory workflows. Modern dyes designed to increase panel size have proven hugely popular in the wake of the COVID-19 pandemic, enabling researchers to generate increasingly data-rich results despite being unable to work in the lab full-time. Advances in flow cytometry instrumentation have also been beneficial in the current climate, with a topical example being Bio-Rad’s small particle upgrade to the ZE5 Cell Analyzer that allows detection of nanoscale particles such as viruses. And machine learning and artificial intelligence (AI) continue to extend their reach into countless fields, especially those renowned for generating vast quantities of data such as high-content screening and imaging flow cytometry.
Novel dyes increase multiplexing capacity
Manufacturers are continually developing new dyes to make flow cytometry panel design more flexible. Recent newcomers to an already extensive range of fluorochromes include BD Biosciences’ Horizon™ Red 718 (designed to provide greater resolving power than Alexa Fluor® 700) and Horizon Brilliant™ Ultraviolet 615 (a tandem dye excited by the ultraviolet laser, with an emission maximum of 616 nm), and Bio-Rad’s StarBright dyes that combine exceptional brightness with specific excitation and emission profiles. In addition, Phitonex’ novel Phiton™ Platform Technology enables customizable creation of fluorescent nanoparticles known as Phitons™ that benefit from high fluorescence transfer efficiencies, minimized cross-excitation, and reduced spectral spillover. Other next-generation fluorochromes are Biotium’s CF® dyes that span the visible, far-red, and near-IR spectra and claim superior brightness, photostability, and signal-to-noise ratio when compared to other commercially available fluorescent dyes, and BioLegend’s Spark and Fire™ dyes that were created to fill gaps between existing fluorochromes. Many of the Spark and Fire™ dyes can be used for spectral cytometry; for example, Spark Violet™ 538 can be successfully unmixed from neighboring dyes such as BV510™, BV570™, and BV605™, while PE/Fire™ 640 has a distinct emission peak that falls between the peaks of PE/Dazzle™ 594 and PE/Cyanine5.
Thermo Fischer joins the spectral flow arena Spectral flow cytometry has seen significant uptake in the last few years, largely because it allows panel size to be increased to upward of 40 fluorochromes (the current maximum is 44). Until recently, Sony and Cytek® were the two main players in this field, with Sony launching the first commercially available spectral analyzer (the SP6800) in 2012 and Cytek® following this with its Aurora in 2017. These have since been complemented by Sony’s ID7000™ and the Cytek® Northern Lights. However, via acquisition of Propel Labs technology, Thermo Fisher has now joined the spectral flow arena with the Bigfoot Spectral Cell Sorter. The Bigfoot provides both spectral analysis and spectral sorting and is equipped with various features that enable continuous operation. Nanoscale particle detection becomes more accessible Sub-micron particles such as viruses, extracellular vesicles, and subcellular organelles have historically been difficult to detect using conventional flow cytometers. Not only do they have fewer surface markers than cells, but they are also easily obscured by the presence of cell debris in sample buffers. To address this issue, flow cytometry instrumentation has evolved to provide the higher sensitivity required for nanoscale particle detection. Instrumentation for nanoscale flow cytometry includes Agilent Technologies’ NovoCyte Quanteon that uses a proprietary photomultiplier technology to capture and gate both very dim and very bright signals in the same view, and Beckman Coulter’s CytoFLEX platform that has been optimized to detect and resolve 30 nm polystyrene and 50 nm silica nanoparticles. Other systems providing nanoscale particle detection are Miltenyi’s MACSQuant Analyzer 16 flow cytometer that is fitted with violet side scatter optics for nanoparticle analysis and Bio-Rad’s ZE5 Cell Analyzer that can easily be upgraded with a small particle detector kit to increase the sensitivity of the 405 nm laser.
High-content imaging continues to evolve
Moving away from flow cytometry, high-content imaging also continues to expand in scope. Newer systems are designed to support emerging applications such as the study of complex disease models (e.g., live cells, primary cells, and microtissues), 3D organoid and spheroid imaging, and fast-response assays like Ca2+ flux. Thermo Scientific’s CellInsight™ CX7 LZR provides 7-channel fluorescent imaging and can combine widefield and confocal imaging in the same run, while PerkinElmer’s Opera Phenix® Plus High Content Screening System (launched at SLAS2020) allows automated exchange of the sample plate, tip racks and compound plate (e.g., using the cell::explorer™ automated workstation) and features a liquid handling module that is compatible with brightfield imaging.
Machine learning and AI provide novel insights
Understanding the vast quantities of data generated by techniques such as flow cytometry and high-content imaging has inevitably led to machine learning and artificial intelligence (AI) being integrated into data analysis software. Molecular Devices’ ImageXpress Confocal HT.ai High-Content Imaging System uses machine learning to perform complex classification automatically, improving the characterization of individual cell populations, while Luminex has extended machine learning and AI to the realm of imaging flow cytometry, with both the Amnis® ImageStream®X Mk II and the Amnis® FlowSight® imaging flow cytometers being compatible with the company’s Machine Learning for IDEAS® 6.3 and Amnis® AI Image Analysis software packages. Whether you’re performing flow cytometry, high-content screening, imaging flow cytometry, or any other technique that uses fluorochromes, you can depend on us to help you through the critical process of panel design. FluoroFinder’s Spectra Viewer lets you quickly compare over 900 fluorochromes from all suppliers in one intuitive platform, while our Panel Builder enables you to optimize your multiplexed experiments with the very latest fluorochrome and antibody offerings across >60 suppliers. Take advantage of everything that the latest technologies have to offer by using our platforms today! Sign up for our eNewsletter to receive further updates.