Figure 1. Phase (i), fluorescence (ii), and combined (iii), images of RAW 264.7 macrophages incubated (24 h) with red fluorescent (λem. 640 nm) silicon nanoparticles (<4 nm in Dia.). A: Control (RAW 264.7), B: SNs concentration of 20 µg/ml, C: SNs concentration of 50 µg/ml, scale bar: 30 μm.
Figure 2. Effect of SNs and SMs on cell survival percentage in RAW 264.7 cells based on trypan blue dye exclusion (A) and MTT (B) assay. Cells were treated with different concentrations (0.1~200 μg/ml) of SNs and SMs for 24 and 48 h. At the end of treatment, trypan blue stain was added to a oliquot of cells to assess the cell live/dead ratio (A). Yellow MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) was introduced into the 96 wells containing cells incubated for 24h with either nano or microparticles. Live cells convert the yellow colored dye to purple color which is then measured with a fluorescence plate reader. * and # indicate a statistical difference from the control, p<0.05.