Figure 3.
Cell viability and evaluation of cellular uptake of EL-NPs. (A and B) Live-dead assay on cells treated with and without EL-NPs showing no change in cell viability; green = viable cells, red = dead cells. (C) Cellular exclusion of EL-NP of large (> 200nm) nanoparticles with negative surface charge and (D) uptake of small (<100nm) nanoparticles with negative surface charge, (E) small particles treated with poly-L-lysine to create positive surface charge and (F) large particles treated with poly-L-lysine positive surface charge. Negatively charged EL-NPs are excluded by cells when size >200nm compared to <100nm particles. Increasing positive surface charge enhances cellular uptake even of larger particles. Yellow = DiI stained cell membrane, Blue = DAPI stained nucleus, Purple = DIR dye encapsulated nanoparticles.