A dual-targeting upconversion nanoplatform for two-color fluorescence imaging-guided photodynamic therapy.

The targetability of a theranostic probe is one of the keys to assuring its theranostic efficiency. Here we show the design and fabrication of a dual-targeting upconversion nanoplatform for two-color fluorescence imaging-guided photodynamic therapy (PDT). The nanoplatform was prepared from 3-aminophenylboronic acid functionalized upconversion nanocrystals (APBA-UCNPs) and hyaluronated fullerene (HAC60) via a specific diol-borate condensation. The two specific ligands of aminophenylboronic acid and hyaluronic acid provide synergistic targeting effects, high targetability, and hence a dramatically elevated uptake of the nanoplatform by cancer cells. The high generation yield of (1)O2 due to multiplexed Förster resonance energy transfer between APBA-UCNPs (donor) and HAC60 (acceptor) allows effective therapy. The present nanoplatform shows great potential for highly selective tumor-targeted imaging-guided PDT.