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EVOS™ Cell Imaging Systems

You should choose based upon the complexity of your labs’ analyses and whether you need transmitted (color) camera imaging or fluorescent (monochrome) camera imaging, or both. At routine/basic analyses, we offer the EVOS™ XL Core Imaging System for simple transmitted light imaging (typically used in cell culture facilities) or the FLoid™ Cell Imaging Station for dedicated three-color fluorescence imaging. The EVOS™ XL Imaging System differs from the EVOS™ XL Core Imaging System in that it has a larger monitor, a five objective turret (only four objectives with the EVOS™ XL Core instrument), can be networked, and can perform cell counting. 

 If you need more options for fluorescent wavelengths, cell counting, or time-lapse imaging, you may consider the EVOS™ FL Imaging System or the EVOS™ FL Auto Imaging System. The EVOS™ FL Auto Imaging System is our most versatile option, featuring automated imaging and more. It has both color and monochrome camera options, and can even be paired with our EVOS™ Onstage Incubator system.

Compare the capabilities of the EVOS™ Systems.

Yes, the Countess™ II FL instrument uses the same light cubes as the EVOS™ imaging systems. The Countess™ II instrument does not use light cubes.

All the EVOS™ imaging systems are inverted microscopes. For CC objectives, the coverslip must be face down, facing the objectives as the lenses have a short working distance suitable only for thin glass or plastic coverslips. LWD objectives are designed for viewing from the bottom of microplates, petri dishes, or culture flasks; the longer working distances of the lenses in these objectives accommodate thicker materials such as the plastic bottoms of various vessels. 

The FLoid™ Cell Imaging Station is a simple, easy-to-use transmitted-light and three-color fluorescence microscope. The three fluorescent colors, blue, green, and visible red (Texas Red™ dye) are set and cannot be changed to other filter sets. The magnification is also set with a 20x objective; this objective cannot be removed or changed.

On the other hand, the EVOS™ FL Imaging Systems are easy-to-use transmitted-light and fluorescence microscopes that allow the user access to the objective turret and light cube tray to permit multiple options for magnification and fluorescence detection. The EVOS™ FL Imaging Systems allow the use of 23 different light cubes and 18 different objectives (from 2x to 100x). 

  • Plan Achromat objectives are perfect for general applications where color and focus have standard correction; these are suitable for samples requiring low magnification (2x to 4x). Plan Achromat objectives are recommended for basic brightfield microscopy and simple fluorescence detection.
  • Plan Fluorite objectives provide the next level of improved resolution for brighter fluorescence signal and high contrast. These objectives are recommended for basic fluorescence imaging and brightfield microscopy at higher magnifications.
  • Plan Apochromat provides the highest level of resolution, fluorescence brightness, contrast, and chromatic correction. If you are imaging very small structures and require high contrast and brightness, the Plan Apochromat objectives are the best option.

The GFP light cube (Ex = 470/22; Em = 510/42) has excitation centered at 470 nm covering 11 nm on each side for a total excitation range from 459 to 481 nm. Its emission is centered at 510 nm with 21 nm on each side for a total emission bandpass range from 489 to 531 nm. 

  • The Qdot™ 525 light cube (Ex = 445/45; Em = 525/15) has excitation at 445 nm with 22.5 nm on each side for a total excitation range from 422.5 to 467.5. Its emission is centered at 525 nm with 7.5 nm on each side for a total emission bandpass range from 517.5 to 532.5. 
  • The GFP light cube is best suited for fluorophores that are efficiently excited from 460 to 480 nm and emission with in the blue-green to green range. 
  • The Qdot™ 525 light cube is better suited for exciting quantum dots at lower wavelengths (higher energy) and provides a narrower emission in the green range. 

Only the EVOS FL Auto Imaging System and EVOS FL Auto 2 Imaging System have an automatic cell counting function. The EVOS XL, EVOS FL, and EVOS FL Color imaging systems provide a manual cell counting tool that allows you to tag up to six different labels on the screen image.

High-Content Analysis (HCA)/High-Content Screening (HCS) Systems

The basic differences are in the number of channels for excitation (5 versus 7), the ability to image in brightfield, widefield, and confocal, and the number of positions available on the objective turret. The CellInsight™ CX5 System is the most basic HCS system with illumination in 5 channels, imaging in brightfield and widefield, and a 1-position objective turret. The CellInsight™ CX7 System and ArrayScan™ System provide illumination in 7 channels, imaging in brightfield, widefield, and confocal, and either a 3-position (CX7) or 4-position objective turret (ArrayScan™ System). The ArrayScan™ System has the added option of live-cell imaging. For more information, go here.

Contact Instrument Customer Services for any issues regarding the CellInsight™ systems and ArrayScan™ System. They can be reached at

Reagents and Consumables for Cell Imaging

Some cell types accumulate phenol red, and this can pose a problem in the use of many fluorescent probes. Phenol red can quench visible-wavelength dyes and, although phenol red is non-fluorescent, various impurities may be fluorescent. We have many phenol red-free media to choose from. Our Live Cell Imaging Solution (HEPES-based) and our FluoroBrite™ DMEM have been optimized to be phenol red-free as well as to be non-autofluorescent.

Most media contain phenol red, which can quench fluorescent dyes in the visible wavelengths. Most media also contain autofluorescent components, such as riboflavin, which can reduce signal-to-background. We offer FluoroBrite™ DMEM and HEPES-based Live Cell Imaging Solution, which have been optimized for fluorescent imaging. We also offer a number of media without phenol red. But if none of these are reasonable options for your experiment, then we also offer BackDrop™ Background Suppressor ReadyProbes™ Reagent, which can be added to quench media autofluorescence.

As dyes are illuminated for imaging, they will fade, or “photobleach”, leading to unwanted dimming and lower detection efficiency over time. An antifade mounting medium can greatly reduce photobleaching. If you wish to label live cells, use of ProLong™ Live Antifade Reagent is helpful. If you wish to mount fixed cells after labeling, and then image immediately and then discard, SlowFade™ Diamond Antifade Mountant stays liquid but has good refractive index. If you wish to mount your sample and then archive the slides, ProLong™ Diamond Antifade Mountant will harden to a better refractive index and allow for archiving of the sample for up to several weeks, or even months. Unlike other antifade mounting media, these work well with fluorescent proteins for immediate viewing (archiving fluorescent proteins is not possible), and they are packaged with or without DAPI. More information on these can be found here.