Why is it necessary to optimize the cell density used for studies with alamarBlue®?
alamarBlue® measures cell proliferation most accurately when the cells are in the exponential growth phase. If the cell density is too high, cell proliferation will decrease, giving less reduction of the alamarBlue® than would have been expected. At low cell density, the slower growth rate could result in insignificant alamarBlue® reduction. A cell density of 1 x 10e4 cells/ml is generally recommended, which often corresponds to cells being in the exponential phase. However, since cells vary in their proliferation rate, it is impossible to recommend a cell density which is suitable for all experiments. Instead we recommend that customers perform a control experiment to determine the optimum cell density for their studies. It is equally important to optimize the incubation time for alamarBlue®. Please refer to Worked example 1 for the general method to determine the optimum cell density and incubation time. Figure 1: A standard bacterial growth curve.
