Multifunctional Smart Yolk–Shell Nanostructure with Mesoporous MnO2 Shell for Enhanced Cancer Therapy
journal contributionposted on 21.08.2020, 02:34 authored by Hongjun Zhuang, Mengyao Zhao, Shenglong Ding, Lingyan Liu, Wei Yuan, Liping Jiang, Xuemin Han, Libo Jiang, Tao Yi
Manganese dioxide (MnO2) nanostructures have aroused great interest among analytical and biological medicine researchers as a unique type of tumor microenvironment (TME)-responsive nanomaterial. However, reliable approaches for synthesizing yolk–shell nanostructures (YSNs) with mesoporous MnO2 shell still remain exciting challenges. Herein, a YSN (size, ∼75 nm) containing a mesoporous MnO2 shell and Er3+-doped upconversion/downconversion nanoparticle (UCNP) core with a large cavity is demonstrated for the first time. This nanostructure not only integrates diverse functional components including MnO2, UCNPs, and YSNs into one system but also endows a size-controllable hollow cavity and thickness-tunable MnO2 layers, which can load various guest molecules like photosensitizers, methylene blue (MB), and the anticancer drugs doxorubicin (DOX). NIR-II fluorescence and photoacoustic (PA) imaging from UCNP and MB, respectively, can monitor the enrichment of the nanomaterials in the tumors for guiding chemo-photodynamic therapy (PDT) in vivo. In the TME, degradation of the mMnO2 shell by H2O2 and GSH not only generates Mn2+ for tumor-specific T1-MR imaging but also releases O2 and drugs for tumor-specific treatment. The result confirmed that imaging-guided enhanced chemo-PDT combination therapy that benefited from the unique structural features of YSNs could substantially improve the therapeutic effectiveness toward malignant tumors compared to monotherapy.