This homogeneous assay involves simply adding a single reagent, the CellCount -Blue reagent, to the cell culture and measuring the fluorescence intensity (excitation wavelength = 530-570 nm, emission wavelength = 590-620 nm after an incubation step. The CellCount-Blue reagent, utilizes the redox dye resazurin whichis not fluorescent, but upon reduction by metabolically active cells is converted into a highly fluorescent product (resorufin). Living cells can readily reduce this non-toxic reagent and the resulting increase in fluorescence intensity can be conveniently monitored using a luorescence specturophotometer or plate reader. Nonviable cells have no metabolic capacity and, thus, will not reduce the dye. Therefore, the fluorescence intensity observed in this assay is a true measure of the viable cells. The CellCount-Blue reagent has been optimized for maximum sensitivity, reproducibility and long shelf-life. The homogeneou cell-based assay can be performed in multi-well plates.
The reagent is comparible with all culture media and with all liquid handling systems for high-throughput screening applications in 96-well and 384 -well plates. Appli -cations include cell proliferation, cytotoxicity and apoptosis.