Figure 2: CT image of a mouse before administration (a) and 2 minutes after administration of gold nanoparticles (b) and commercial iodinated contrast agent Omnipaque®. It is readily apparent that the gold nanoparticles allow clear visualization of the vasculature structure revealing increased vascularization in the left leg (arrow) indicative of a tumour. Scale bar = 5mm. (From: Gold nanoparticles a new X-ray contrast agent - Hainfeld JF - The British Journal of Radiology 2006) [76].