To investigate whether the fluorescence stains or the staining process alters leukocyte deformability to affect their distribution after sorting, experiments were performed to compare the outlet distributions of whole blood samples without stain, with Hoechst 33342 stain, as well as with fluorescently conjugated markers using samples from the same donor. As shown in Fig. 5I, the leukocyte distribution is very consistent, which confirms that fluorescence staining has no effect on leukocyte deformability.