Hierarchical MoSe2 nanoflowers as novel nanocarriers for NIR-light-mediated synergistic photo-thermal/dynamic and chemo-therapy

Abstract

The construction of nanoplatforms that integrate multiple therapies has attracted much attention in the field of cancer treatment. Herein, selenide molybdenum (MoSe₂) nanoflowers were synthesized as nanocarriers capable of delivering NIR-mediated synergetic photothermal therapy (PTT), photodynamic therapy (PDT), and drug release. All of the MoSe₂ nanoflowers (150–180 nm) are made up of many thin nanosheets of about 3–4 layers of MoSe₂. With the novel hierarchical nanostructure and small band gap (1.24 eV), the as-synthesized MoSe₂ nanoflowers possess strong near-infrared (NIR) absorption and high photothermal conversion efficiency (61.8%). In addition, they also exhibit NIR-stimulated ˙OH generation and this is the first time that MoSe₂ nanostructures have been used as a PDT agent. The mechanism was investigated, which revealed that a sufficient number of photo-excited electrons and high O₂ and H⁺ concentrations facilitate ˙OH production. After PEGylation, MoSe₂@PEG exhibits high Dox-loading capacity due to electrostatic and π–π stacking interactions. After drug loading, the resulting MoSe₂@PEG-Dox system exhibits acid/photothermal-triggered drug release. The synergistic effect of chemotherapy, PTT and PDT further induces superior cancer cell apoptosis and improved antitumor effectiveness.