MRI nanoprobes based on chemical exchange saturation transfer: LnIII chelates anchored on the surface of mesoporous silica nanoparticles

Abstract

The formation of ternary complexes between neutral Ln^III–DO3A chelates anchored on MCM-41 mesoporous silica nanoparticles (MSNs) and silanol groups on the surface allows obtaining highly efficient chemical exchange saturation transfer (CEST) MRI nanoprobes. These new probes achieve excellent sensitivity in the μM range (per Ln^III ion), significantly greater than that of other paramagnetic CEST nanosystems such as dendrimers or micelles and three orders of magnitude higher than that of the corresponding molecular agents.