Plasmonic gadolinium oxide nanomatryoshkas: bifunctional magnetic resonance imaging enhancers for photothermal cancer therapy.

Nanoparticle-assisted laser-induced photothermal therapy (PTT) is a promising method for cancer treatment; yet, visualization of nanoparticle uptake and photothermal response remain a critical challenge. Here, we report a magnetic resonance imaging-active nanomatryoshka (Gd 2 O 3 -NM), a multilayered (Au core/Gd 2 O 3 shell/Au shell) sub-100 nm nanoparticle capable of combining T 1 MRI contrast with PTT. This bifunctional nanoparticle demonstrates an r 1 of 1.28 × 10 8 mM -1 s -1 , an MRI contrast enhancement per nanoparticle sufficient for T 1 imaging in addition to tumor ablation. Gd 2 O 3 -NM also shows excellent stability in an acidic environment, retaining 99% of the internal Gd(3). This report details the synthesis and characterization of a promising system for combined theranostic nanoparticle tracking and PTT.