Surface PEG Grafting Density Determines Magnetic Relaxation Properties of Gd-Loaded Porous Nanoparticles for MR Imaging Applications.

ABSTRACT: Surface PEGylation of nanoparticles designed for biomedical applications is a common and straightforward way to stabilize the materials for in vivo administration and to increase their circulation time. This strategy becomes less trivial when MRI active porous nanomaterials are concerned as their function relies on water/proton-exchange between the pores and bulk water. Here we present a comprehensive study on the effects of PEGylation on the relaxometric properties of nanozeolite LTL (dimensions of 20 × 40 nm) ion-exchanged with paramagnetic Gd^III ions. We evidence that as long as the surface grafting density of the PEG chains does not exceed the "mushroom" regime (conjugation of up to 6.2 wt % of PEG), Gd-LTL retains a remarkable longitudinal relaxivity (38 s^-1 mM

SUBMITTER: Zhang W 

PROVIDER: S-EPMC5520100 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature