Facile Synthesis of Fe3O4@Au/PPy-DOX Nanoplatform with Enhanced Glutathione Depletion and Controllable Drug Delivery for Enhanced Cancer Therapeutic Efficacy.

The complex physiological environment and inherent self-healing function of tumors make it difficult to eliminate malignant tumors by single therapy. In order to enhance the efficacy of antitumor therapy, it is significant and challenging to realize multi-mode combination therapy by utilizing/improving the adverse factors of the tumor microenvironment (TME). In this study, a novel Fe3O4@Au/PPy nanoplatform loaded with a chemotherapy drug (DOX) and responsive to TME, near-infrared (NIR) laser and magnetic field was designed for the combination enhancement of eliminating the tumor. The Fe2+ released at the low pH in TME can react with endogenous H2O2 to induce toxic hydroxyl radicals (·OH) for chemodynamic therapy (CDT). At the same time, the generated Fe3+ could deplete overexpressed glutathione (GSH) at the tumor site to prevent reactive oxygen species (ROS) from being restored while producing Fe2+ for CDT. The designed Fe3O4@Au/PPy nanoplatform had high photothermal (PT) conversion efficiency and photodynamic therapy (PDT) performance under NIR light excitation, which can promote CDT efficiency and produce more toxic ROS. To maximize the cancer-killing efficiency, the nanoplatform can be successfully loaded with the chemotherapeutic drug DOX, which can be efficiently released under NIR excitation and induction of slight acidity at the tumor site. In addition, the nanoplatform also possessed high saturation magnetization (20 emu/g), indicating a potential magnetic targeting function. In vivo and in vitro results identified that the Fe3O4@Au/PPy-DOX nanoplatform had good biocompatibility and magnetic-targeted synergetic CDT/PDT/PTT/chemotherapy antitumor effects, which were much better than those of the corresponding mono/bi/tri-therapies. This work provides a new approach for designing intelligent TME-mediated nanoplatforms for synergistically enhancing tumor therapy.

Construction and synergistic anticancer efficacy of magnetic targeting cabbage-like Fe3O4@MoS2@ZnO drug carriers.

A novel cabbage-like Fe3O4@MoS2@ZnO nanocomposite was successfully fabricated through a facile method. The as-prepared nanocomposite exhibited a saturation magnetization of 45 emu g-1 as well as possessed a massive pore structure and large surface area, leading to a high DOX loading capacity of 68.14 µg mg-1; it could effectively deliver drugs to tumor lesion sites under the action of magnetic targeting. The pH-dependent ZnO as a packaging component can block the pores to achieve controlled release of DOX under tumor stimulation conditions (pH 6.5), thereby reducing the side effects of DOX on normal cells and increasing its therapy effects on tumor cells. Moreover, the photothermal conversion efficiency contributed by MoS2 under 808 nm NIR laser irradiation was utilized to realize effective photothermal therapy (PTT) of cancer, which could be integrated with chemotherapy in a single system. Thus, the resulting Fe3O4@MoS2@ZnO nanocomposites provide hopeful prospects in biomedical applications based on pH sensitivity, magnetic targeting and chemo-photothermal synergistic therapy.

Litchi-like Fe3O4@Fe-MOF capped with HAp gatekeepers for pH-triggered drug release and anticancer effect.

A novel litchi-like porous composite composed of a magnetic core, a tunable metal-organic framework (MOF) shell and a pH-sensitive hydroxyapatite (HAp) gatekeeper was successfully fabricated in this work. The anticancer drug doxorubicin (DOX) was effectively loaded on the Fe3O4@Fe-MOF@HAp nanocomposite with a loading capacity of 75.38 mg g-1. The nanocomposite had a saturation magnetization of 34 emu g-1 and thus possessed magnetic targeting function. In addition, the HAp gate, which had favorable biocompatibility and pH response characteristics, could be used to control the release of loaded DOX from the Fe3O4@Fe-MOF@HAp nanocomposite microspheres in a simulated acidic tumor cell environment, effectively killing tumor cells and reducing the toxic side effects to normal tissue. The smart design presented in this study, which incorporates a tunable shell and gate-controlled architecture, allows the sensitive release of drugs for efficient antitumor activity.

Reduced Graphene Oxide/Amaranth Extract/AuNPs Composite Hydrogel on Tumor Cells as Integrated Platform for Localized and Multiple Synergistic Therapy.

Integration of multimodal treatment strategies combined with localized therapy to enhance antitumor efficacy and reduce side effects is still a challenge. Herein, a novel composite hydrogel containing rGO, amaranth extract (AE) and gold nanoparticles (AuNPs) was prepared by using AE as both reductant and cross-linking agent. The chlorophyll derivatives in AE were also employed as a photodynamic therapy drug. Meanwhile, AuNPs and rGO both have obvious photothermal effects and can accelerate the generation of cytotoxic singlet oxygen (1O2). The temperature increase of rGO/AE/AuNPs precursor is up to 6.3 °C under 808 nm laser irradiation at a power density of 200 mW·cm(-2). The hydrogel shell on in situ tumor cells was easily formed and regulated by near-infrared irradiation within 10 min, which could both retain a high concentration of drugs on the lesion site and prevent them from migrating to normal tissue, thus reducing the side effects. Compared with rGO/AE and AE, rGO/AE/AuNPs showed a remarkably improved and synergistic antitumor effect. The hydrogel possesses good biocompatibility and high hydrophilicity and could be used for loading chemotherapeutics, which provides a new approach for located and multiple antitumor therapies.