Dendrimer-functionalized LAPONITE® nanodisks loaded with gadolinium for T1-weighted MR imaging applications

In this report, we present a facile approach to forming dendrimer-functionalized LAPONITE (R) (LAP) nanodisks loaded with gadolinium (Gd) for in vitro and in vivo T-1-weighted MR imaging applications. In this work, LAP nanodisks were sequentially modified with silane coupling agents, succinic anhydride to have abundant carboxyl groups on their surface, and amine-terminated poly(amidoamine) (PAMAM) dendrimers of generation 2 (G2). The dendrimer-modified LAP nanodisks were then conjugated with gadolinium (Gd) chelator diethylenetriaminepentaacetic acid (DTPA), followed by Gd(III) chelation to form the LM-G2-DTPA (Gd) nanocomplexes. The designed LM-G2-DTPA(Gd) nanocomplexes were characterized via different techniques. Cell viability assay shows that the formed LM-G2-DTPA(Gd) nanodisks are non-cytotoxic in the given concentration range. With a high r(1) relaxivity (2.05 mM(-1) s(-1)), the LM-G2-DTPA(Gd) nanocomplexes are able to be used as an efficient contrast agent for T-1-weighted MR imaging of cancer cells in vitro and animal organ/tumor model in vivo. The designed LM-G2-DTPA(Gd) nanocomplexes may hold a great promise to be used as a versatile nanoplatform for MR imaging of different biological systems.