Double-Layered Plasmonic-Magnetic Vesicles by Self-Assembly of Janus Amphiphilic Gold-Iron(II,III) Oxide Nanoparticles.

Janus nanoparticles (JNPs) offer unique features, including the precisely controlled distribution of compositions, surface charges, dipole moments, modular and combined functionalities, which enable excellent applications that are unavailable to their symmetrical counterparts. Assemblies of NPs exhibit coupled optical, electronic and magnetic properties that are different from single NPs. Herein, we report a new class of double-layered plasmonic-magnetic vesicle assembled from Janus amphiphilic Au-Fe O NPs grafted with polymer brushes of different hydrophilicity on Au and Fe O surfaces separately. Like liposomes, the vesicle shell is composed of two layers of Au-Fe O NPs in opposite direction, and the orientation of Au or Fe O in the shell can be well controlled by exploiting the amphiphilic property of the two types of polymers.