Alamar Blue™ is a safe, nontoxic, aqueous dye that is used to assess cell viability and cell proliferation and is supplied as a sterile indigo-colored liquid. Alamar Blue has also been shown to be a rapid and simple non-radioactive assay alternative to the [3H] thymidine incorporation assay. AlamarBlue contains resazurin and additional compounds to prevent the over-reduction of resazurin to a non-fluorescent product. These additives also slow the rate of generation of the fluorescent product. Consequently, the alamarBlue assay requires longer incubation times compared to resazurin.
Applications:Suitable for use in Cell Viability Assessment and Cell Proliferation Assessment in Immunofluorescence and ELISA.
Cell Viability Assessment:The innate metabolic activity of cells can be monitored with Alamar Blue™. In the presence of added toxic compounds such as antimicrobial agents, this innate metabolic activity ceases. Procedures which cite the use of Alamar Blue™ in assays of efficacy of antimicrobial agents call for the determination of Alamar Blue™ reduction at a single predetermined time point.
Cell Proliferation Assessment:Alamar BlueTM is soluble, stable in culture medium and is non-toxic. The continuous monitoring of cells in culture is therefore permitted. Specifically, Alamar Blue™ does not alter the viability of cells cultured for various times as monitored by Trypan Blue exclusion. Cells grown in the presence of Alamar Blue™ and subsequently analyzed by Flow Cytometry for CD44, CD45RB, CD4 and heat stable antigen are found to produce similar numbers of viable cells and antigen expressing cells as non- Alamar Blue™ exposed cells. Because Alamar Blue™ is non-toxic, the cells under study can be returned to culture or used for other purposes including histological studies. Proliferation measurements with Alamar Blue™ may be made either spectrophotometrically by monitoring the absorption of Alamar Blue™ supplemented cell culture media at two wavelengths. Alternatively, proliferation measurements with Alamar Blue™ may be made fluorometrically.
Storage and Stability:May be stored at 4°C, -20°C or -70°C. When stored frozen, it is important to warm to 37°C upon thawing and mixed well to be assured of complete resolubilization. Protect from light. Storage at RT under lighted conditions adversely affects its absorbance properties.
