Fig. 3.

Multimodality in vivo imaging of siRNA nanoparticle delivery and function, using micro-PET/CT and BLI. (A) Fused micro-PET/CT images showing tumor-associated (arrow) activity 1 d after injection of targeted (Tf) and nontargeted (PEG) nanoparticles containing ⁶⁴Cu-DOTA-siRNA. (B) BLI of the same mice shown in A before injection and 1 d after injection. (C) Relative change in luciferase expression 1 d after injection of Tf-targeted (Tf, n = 7) and nontargeted (PEG, n = 4) nanoparticles containing ⁶⁴Cu-DOTA-siRNA for simultaneous PET imaging. Error bars indicate SE.