The two kits utilize different dyes and background suppressors, but they function in the same way and provide similar results as can be seen from Figures 1 and 2 in the CyQUANT Direct Red Cell Proliferation Assay product sheet (https://assets.thermofisher.com/TFS-Assets/LSG/manuals/MAN0018644_CyQUANT_direct_red_assay_PI.pdf). Dyes from both kits are nucleic acid stains and the background suppressors are cell impermeant reagents that quench extracellular fluorescence. They are usable within the same range (100 to 20,000 cells/well in a 96-well format) and in the same workflow.
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