EXPLORING HETEROSTRUCTURED UPCONVERSION NANOPARTICLES: FROM RATIONAL PARTICLE ENGINEERING TO BIOMEDICAL APPLICATIONS

Upconversion nanoparticle (UCNP)-based photodynamic therapy (PDT) with unique anti-stokes luminescence features are of great interest. UCNP-based PDT affords greater tissue penetration depths than that of visible lights and serves as suitable nanoplatforms carrying photosensitizers as well. However, UCNP-based PDT is not only restricted by its intrinsic limited quantum efficiency but also has a poor drug distribution inside solid tumors whose interiors are poorly vascularized. To resolve the above issues, firstly, asymmetric silica-coated UCNPs were prepared with tunable silica coverage ratio and morphology. On one hand, through stepwise passivation on the asymmetric architecture, the off-on effect at the core-shell interface explicitly indicated the long-neglected significance of full shell coating on the luminescent core nanoparticle to enhance the upconversion luminescence intensity. On the other hand, nitric oxide propelled Janus upconversion nanomotors were designed, which has better diffusion characteristics throughout the solid tumor and delivers an enhanced near-infrared triggered PDT.

Author dc:creator

• ZHANG YI

• Upconversion, heterostructured silica, core-shell interface, Janus nanomotors, enhanced diffusion, photodynamic therapy