Figure 3: Analysis of nanoparticles accumulation in the tumor tissue after 4 h of dose administration. (a) Histopathological images of SW480 colon cancer tissue stained dark brown in color, indicating the presence of scrambled biotinylated siRNA (0.5 mg/kg) in the tumor tissue after intraperitoneal administration of the treatment nanoparticle formulation. Animals were sacrificed after 4 hrs. (A) Chitosan-PEG-CP15 (B) Unmodified chitosan nanoparticles (C) non-targeting biotin siRNA alone, (D) control: untreated. (b) Image analysis of the mean percent area stained in the tumor tissues. The graph shows a representative result of the average of three random sections measured per animal tissue, mean ± SD. , .