Figure 2

X-ray micrographs of the microvasculature of the leg area of a tumor bearing mouse taken after injection of MUA-coated AuNP. In vivo snapshots like (a) were taken from a sequence of microradiology images 5 min after the injection; the vessel size marked by the arrow in the inset is ~10 μm. (b) Magnified images of the dotted-line square portion of (a) showing a region of extravascular diffusion of the contrast agent. The scale bars are (a) 500 μm, (b) 250 μm, inset in (a) 50 μm. (c) and (d) are high resolution X-ray microscopy images of MUA-coated AuNPs in muscle and in tumor microvessels. Some microvessels with rather small diameter, ~3 μm, are marked by arrowheads. Substantial extravascular diffusion is found in tumor area. The scale bar in (c) and (d) is 5 μm