Superior sagittal sinus blood plasma Gd concentration curves over 2 hours following 1 minute bolus intravenous infusion of Gd-DTPA dendrimer generations G1 through G8 infusions at dose of 0.09 mmol Gd/kg body weight (bw). Blood plasma concentrations measured via dynamic contrast-enhanced MRI-based analysis by selection of 5-to-10 voxels in the superior sagittal sinus (SSS) free from partial volume averaging effects. Gd-G1 (n = 5), Gd-G2 (n = 6), Gd-G3 (n = 6), lowly conjugated (LC) Gd-G4 (n = 4), standard (Std) Gd-G4 (n = 6), Gd-G5 (n = 6), Gd-G6 (n = 5), Gd-G7 (n = 5) and Gd-G8 (n = 6). Gd-G5 through Gd-G8 dendrimers rapidly reach and maintain a steady state in blood over 2 hours (G6, G7 and G8 not shown for clarity). Error bars represent standard deviation (s.d.) and are shown once every five minutes for clarity. Adapted from references [3,8,28].