Size-Controlled Self-Assembly for Bimodal In Vivo Imaging.

Contrast agents (CAs) are essential in biomedical imaging to aid in the diagnosis and therapy monitoring of disease. However, they are typically restricted to one imaging modality and have fixed properties such as size, shape, toxicity profile, or photophysical characteristics, which hampers a comprehensive view of biological processes. Herein, rationally designed dye assemblies are introduced as a unique CA platform for simultaneous multimodal and multiscale biomedical imaging.

Superparamagnetic Nanoparticles with Phosphorescent Complexes as Hybrid Contrast Agents: Integration of MRI and PLIM.

Two different hybrid nanosystems are prepared by loading highly crystalline, monodisperse magnetite nanocubes (MNCs) with phosphorescent Pt(II) complexes (PtCxs). One involves the encapsulation of the hydrophobic PtCx1 within an amphiphilic comb polymer (MNC@poly(maleic anhydride--1-octadecene) [PMAO]-PtCx1), whereas the other involves the direct binding of the hydrophilic PtCx2 to the surface of the MNC mediated by a ligand-exchange procedure (MNC@OH-PtCx2). Both systems are evaluated as potential candidates for multimodal imaging in magnetic resonance imaging (MRI) and photoluminescence lifetime imaging micro(spectro)scopy (PLIM).