Fig. 5.
Luminescence images testing specific targeting of pSiNPs and GO-coated pSiNPs to injured mouse brain. (a) Time-gated luminescence image of injured mouse brains (λex: 365 nm). Dashed white circles indicate region of penetrating brain injury. Targeted ("RVG-conjugated") and non-targeted ("w/o RVG") nanoparticles are compared. Inset: Bright field image (in gray scale) under ambient light. (b) Signal-to-noise ratio (SNR) calculated for luminescent pSiNPs accumulated at healthy (left hemisphere) or injured (right hemisphere) region of the brain tissues. (c) Fluorescence image of Dy677-labeled siRNA accumulated in mouse organs obtained from IVIS 200 imaging system (λex: 670 nm, λem: 700 nm). (d) Relative fluorescence intensity of Dy677-labeled siRNA at healthy (left hemisphere) or injured (right hemisphere) region of the brain tissues. For (b) and (d), * is p < 0.05; ** is p < 0.01; n.s. is not significant, from two-tailed Student’s t test. Data are presented as means ± SD (n = 3).