Gadolinium MRI contrast agents based on triazine dendrimers: relaxivity and in vivo pharmacokinetics.

ABSTRACT: Four gadolinium (Gd)-based macromolecular contrast agents, G3-(Gd-DOTA)(24), G5-(Gd-DOTA)(96), G3-(Gd-DTPA)(24), and G5-(Gd-DTPA)(96), were prepared that varied in the size of dendrimer (generation three and five), the type of chelate group (DTPA or DOTA), and the theoretical number of metalated chelates (24 and 96). Synthesis relied on a dichlorotriazine derivatized with a DOTA or DTPA ligand that was incorporated into the dendrimer and ultimately metalated with Gd ions. Paramagnetic characteristics and in vivo pharmacokinetics of all four contrast agents were investigated. The DOTA-containing agents, G3-(Gd-DOTA)(24) and G5-(Gd-DOTA)(96), demonstrated exceptionally high r1 relaxivity values at off-peak magnetic fields. Additionally, G5-(Gd-DOTA)(96) showed increased r1 relaxivity in seru

SUBMITTER: Lim J 

PROVIDER: S-EPMC3586605 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature