Figure 2.

Cell viability of SH-SY5Y and RAW 264.7 cells. A1 SH-SY5Y cells incubated with MNP-PEI nanoparticles, A2 RAW 264.7 cells incubated with MNP-PEI nanoparticles, B1 SH-SY5Y cells incubated with MNP-PEI-PEG nanoparticles and B2 RAW 264.7 cells incubated with MNP-PEI-PEG nanoparticles. The cells were incubated at different concentrations as indicated over a 72-h incubation. Cell viability was determined using common assays including MTS assay (square), CellTiter-Blue assay (triangle), CellTiter-Glo assay (circle) and trypan blue counting (diamond). (n = 3 ± SE). Asterisk denotes significantly increased level of cell viability compared with trypan blue measurement (p < 0.05).