Stimuli-responsive nanocomposites for magnetic targeting synergistic multimodal therapy and T(1)/T(2)-weighted dual-mode imaging.

Anticancer drug doxorubicin hydrochloride (DOX)-loaded photothermal nanocomposite MnFe2O4@mSiO2 with magnetic targeting and T1/T2-weighted dual-mode magnetic resonance imaging of MnFe2O4 core and NIR/pH-coupling sensitive mesoporous silica shell nanocarriers was designed and synthesized successfully. The anticancer drug DOX can be absorbed into mesoporous layer of MnFe2O4@mSiO2 nanocomposite, which shows obvious photothermal/chemo dual-modal synergistic therapies triggered by NIR/pH. Under 808 nm irradiation, MnFe2O4 can transform light into thermo, which can not only ablate tumor cells directly but also promote chemotherapy drugs releasing from mesoporous layer to kill tumor cells. The lower pH can also promote DOX releasing from mesoporous layer to enhance tumor inhibitory effect. It is confirmed that biocompatible DOX-MnFe2O4@mSiO2 nanocomposites can act as a potential multifunctional platform for effective magnetic targeting photothermal/chemo dual-modal synergistic therapies with enhanced anti-tumor efficacy and T1/T2-weighted dual-mode magnetic resonance imaging (MRI) applications in vivo.

Chen Y ，Deng X ，Li C ，He F ，Liu B ，Hou Z ，Cheng Z ，Xing B ，Lin J ... -  《-》

Two-dimensional magnetic WS2@Fe3O4 nanocomposite with mesoporous silica coating for drug delivery and imaging-guided therapy of cancer.

Integrating multiple imaging and therapy functionalities into one single nanoscale platform has been proposed to be a promising strategy in cancer theranostics. In this work, WS2 nanosheets with their surface pre-adsorbed with iron oxide (IO) nanoparticles via self-assembly are coated with a mesoporous silica shell, on to which polyethylene glycol (PEG) is attached. The obtained WS2-IO@MS-PEG composite nanoparticles exhibit many interesting inherent physical properties, including high near-infrared (NIR) light and X-ray absorbance, as well as strong superparamagnetism. In the mean time, the mesoporous silica shell in WS2-IO@MS-PEG could be loaded with a chemotherapy drug, doxorubicin (DOX), whose intracellular release afterwards may be triggered by NIR-induced photothermal heating for enhanced cancer cell killing. Upon systemic administration of such drug-loaded nano-theranostics, efficient tumor homing of WS2-IO@MS-PEG/DOX is observed in tumor-bearing mice as revealed by three-modal fluorescence, magnetic resonance (MR), and X-ray computed tomography (CT) imaging. In vivo combined photothermal & chemotherapy is then carried out with WS2-IO@MS-PEG/DOX, achieving a remarkably synergistic therapeutic effect superior to the respective mono-therapies. Our study highlights the promise of developing multifunctional nanoscale theranostics based on two-dimensional transition metal dichalcogenides (TMDCs) such as WS2 for multimodal imaging-guided combination therapy of cancer.

Yang G ，Gong H ，Liu T ，Sun X ，Cheng L ，Liu Z ... -  《-》

Fe3O4@mSiO2-FA-CuS-PEG nanocomposites for magnetic resonance imaging and targeted chemo-photothermal synergistic therapy of cancer cells.

Gao Z ，Liu X ，Deng G ，Zhou F ，Zhang L ，Wang Q ，Lu J ... -  《-》

Chemo-photodynamic combined gene therapy and dual-modal cancer imaging achieved by pH-responsive alginate/chitosan multilayer-modified magnetic mesoporous silica nanocomposites.

Yang H ，Chen Y ，Chen Z ，Geng Y ，Xie X ，Shen X ，Li T ，Li S ，Wu C ，Liu Y ... -  《-》

Multifunctional upconversion mesoporous silica nanostructures for dual modal imaging and in vivo drug delivery.

Incorporating the agents for magnetic resonance imaging (MRI), optical imaging, and therapy in one nanostructured matrix to construct multifunctional nanomedical platform has attracted great attention for simultaneous diagnostic and therapeutic applications. In this work, a facile methodology is developed to construct a multifunctional anticancer drug nanocarrier by combining the special advantages of upconversion nanoparticles and mesoporous silica. β-NaYF4 :Yb(3+) , Er(3+) @β-NaGdF4 :Yb(3+) is chosen as it can provide the dual modality of upconversion luminescence and MRI. Then mesoporous silica is directly coated onto the upconversion nanoparticles to form discrete, monodisperse, highly uniform, and core-shell structured nanospheres (labeled as UCNPs@mSiO2 ), which are subsequently functionalized with hydrophilic polymer poly(ethylene glycol) (PEG) to improve the colloidal stability and biocompatibility. The obtained multifunctional nanocomposites can be used as an anticancer drug delivery carrier and applied for imaging. The anticancer drug doxorubicin (DOX) is absorbed into UCNPs@mSiO2 -PEG nanospheres and released in a pH-sensitive pattern. In vitro cell cytotoxicity tests on cancer cells verify that the DOX-loaded UCNPs@mSiO2 -PEG has comparable cytotoxicity with free DOX at the same concentration of DOX. In addition, the T1 -weighted MRI that measures in aqueous solutions reveals that the contrast brightening increases with the concentration of Gd(3+) component. Upconversion luminescence images of UCNPs@mSiO2 -PEG uptaken by cells show green emission under 980 nm infrared laser excitation. Finally, the nanocomposites show low systematic toxicity and high in vivo antitumor therapy efficacy. These findings highlight the fascinating features of upconversion-mesoporous nanocomposites as multimodality imaging contrast agents and nanocarrier for drug molecules.

Li C ，Yang D ，Ma P ，Chen Y ，Wu Y ，Hou Z ，Dai Y ，Zhao J ，Sui C ，Lin J ... -  《-》