Core-satellite metal-organic framework@upconversion nanoparticle superstructures via electrostatic self-assembly for efficient photodynamic theranostics

摘要

The nanoplatforms based on upconversion nanoparticles(UCNPs)have shown great promise in amplified photodynamic therapy(PDT)triggered by near-infrared(NIR)light.However,their practical in vivo applications are hindered by the overheating effect of 980 nm excitation and low utilization of upconversion luminescence(UCL)by photosensitizers.To solve these defects,core-satellite metal-organic framework@UCNP superstructures,composed of a single metal-organic framework(MOF)NP as the core and Nd3+-sensitized UCNPs as the satellites,are designed and synthesized via a facile electrostatic self-assembly strategy.The superstructures realize a high co-loading capacity of chlorin e6(Ce6)and rose bengal(RB)benefitted from the highly porous nature of MOF NPs,showing a strong spectral overlap between maximum absorption of photosensitizers and emission of UCNPs.The in vitro and in vivo experiments demonstrate that the dual-photosensitizer superstructures have trimodal(magnetic resonance(MR)/UCL/fluorescence(FL))imaging functions and excellent antitumor effectiveness of PDT at 808 nm NIR light excitation,avoiding the laser irradiation-induced overheating issue.This study provides new insights for the development of highly efficient PDT nanodrugs toward precision theranostics.