volume to account for extra buffer introduced by filter wetting. 20 μl samples were assayed n=3 times on the haemocytometer. Each sample was randomly imaged at n=5 locations. To estimate the concentrations of all cells and ZsGreen+ cells, images containing DIC, DAPI and ZsGreen channel were analyzed using ImageJ. Sample concentrations were converted into an average total number of cells for each experiment using the volume of the suspension.
