Mutual Benefit between Cu(II) and Polydopamine for Improving Photothermal-Chemodynamic Therapy

Combination therapy has attracted extensive interest in alleviating the shortcomings of monotherapy and enhancing the treatment efficacy. In this work, hollow mesoporous silica nano-particles (HMSNs) play the role of nanocarriers in the delivery of Cu(II)-doped polydopamine (PDA), termed as HMSNs@PDA-Cu, for synergistic therapy. PDA acts as a traditional photothermal agent to realize photothermal treatment (PTT). Chemodynamic therapy (CDT) is realized by the reaction of Cu(II) with intracellular glutathione (GSH), and subsequently, the generated Cu(I) reacts with H2O2 to produce toxic hydroxyl radical ((OH)-O-center dot) through a Fenton-like reaction. The photothermal performance of PDA is improved after its coordination with Cu(II). On the other hand, PDA exhibits superoxide dismutase (SOD)-mimicking activity. PDA converts O-2(center dot)- to H2O2 and improves the production of H2O2, which promotes the therapeutic effect of CDT. Moreover, the high temperature caused by PTT further enhances the yield of (OH)-O-center dot for CDT. This nanotheranostic platform perfectly applied to the tumor depletion of mice, presenting great potential for cancer metastasis therapy in vitro and in vivo.

Automated summary

This study demonstrates the synergistic effect of Cu(II)-doped PDA loaded on HMSNs in combining photothermal therapy and chemodynamic therapy for tumor treatment. PDA contributes to improved photothermal performance and enhanced therapeutic effect of CDT.