Facile Preparation of Multifunctional Upconversion Nanoprobes for Multimodal Imaging and Dual‐Targeted Photothermal Therapy

Jack of all trades: A multifunctional nanoparticle (MFNP) integrates an upconversion nanoparticle (see picture, green), a layer of iron oxide nanoparticles (black), and a gold shell (red). The system can be used for in vitro targeted upconversion luminescence, magnetic resonance, and light scattering multimodal imaging of cells. The near-infrared optical absorption of MFNPs also enables photothermal destruction of cancer cells.