Fig. 6

Pharmacokinetics and bio-distribution of Au@PP/RA/siRNA in vivo. a Pharmacokinetic curves of Au@PP/siRNA and Au@PP/RA/siRNA as analysed by the Au content in the blood using inductively coupled plasma mass spectrometry (ICP-MS), shown as the percentage of the injected dose (% ID). b The bio-distribution of Au@PP/siRNA and Au@PP/RA/siRNA as analysed by the Au content using ICP-MS at 24 h post-injection, expressed as the percentage of the injected dose per gram of tissue (% ID/g). c Ex vivo fluorescence images of representative tumours at 24 h post-injection of Cy5-siRNA, Au@PP/Cy5-siRNA and Au@PP/RA/Cy5-siRNA. d Quantitative analysis of the average fluorescence signal intensity in the tumours. e Distribution of Cy5-siRNA, Au@PP/Cy5-siRNA and Au@PP/RA/Cy5-siRNA in tumours at 24 h post-injection. Blood vessels were stained with CD31 (green) and nuclei were stained with Hoechst 33342 (blue). Scale bars, 50 μm. The data are shown as the mean ± s.d. (n = 3). ^**p < 0.01, ^***p < 0.001 (Student’s t test)