The combination of reactive oxygen species (ROS)-induced chemodynamic therapy (CDT) and photothermal therapy (PTT) holds a promising application prospect for their superb anticancer efficiency. Herein, we created a novel Fe3O4@polydopamine (PDA)@bovine serum albumin (BSA)-Bi2S3 composite as a theranostic agent, by chemically linking the Fe3O4@PDA with BSA-Bi2S3 via the amidation between the carboxyl groups of BSA and the amino groups of PDA. In this formulation, the Fe3O4 NPs could not only work as a mimetic peroxidase to trigger Fenton reactions of the innate H2O2 in the tumor and generate highly cytotoxic hydroxyl radicals (•OH) to induce tumor apoptosis but also serve as the magnetic resonance imaging (MRI) contrast agent to afford the precise cancer diagnosis. Meanwhile, the PDA could prevent the oxidization of Fe3O4, thus supporting the long-term Fenton reactions and the tumor apoptosis in the tumor. The Bi2S3 component exhibits excellent photothermal transducing performance and computed tomography (CT) imaging capacity. In addition, the PDA and Bi2S3 endow the Fe3O4@PDA@BSA-Bi2S3 composite with an excellent photothermal transforming ability which could lead to tumor hyperthermia. All of these merits play the synergism with the tumor microenvironment and qualify the Fe3O4@PDA@BSA-Bi2S3 NPs for a competent agent in the MRI/CT-monitored enhanced PTT/CDT synergistic therapy. Findings in this research will evoke new interests in future cancer therapeutic strategies based on biocompatible nanomaterials.

In this study, we synthesized and characterized a series of Eu(2+) and Mn(2+)-coactivated fluoro-apatite-structure Ca6Y2Na2(PO4)6F2 phosphors, which can provide high-quality standard white emission from a single-phase host. The powder X-ray diffraction, photoluminescence spectra, fluorescence decay curves, chromaticity coordinates, and correlated color temperature of the obtained phosphors were measured and are discussed in detail. Energy transfer from the Eu(2+) to the Mn(2+) ions was demonstrated by the overlap between the emission spectrum of the Eu(2+) ions and the excitation spectrum of the Mn(2+) ions, and the systematic relative decline and growth of the emission bands of Eu(2+) and Mn(2+), respectively. A possible energy transfer mechanism was proposed based on the experimental results and analysis. It was discovered that the emission colors of the phosphor varied from blue through white and eventually to yellow by properly tuning the doping content of Mn(2+) with a fixed Eu(2+) content through the principle of energy transfer. The developed phosphors can be efficiently excited in the UV region and exhibit white-light emission, making them attractive as white-emitting conversion phosphors for UV-based white light emitting diodes.

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In recent years, more and more researches have focused on tumor photothermal therapy and chemodynamic therapy. In this study, we prepared a multifunctional nanomaterial with potential applications in the above area. The Fe 3 O 4 nanoparticles were synthesized with suitable size and uniformity and then coated with mesoporous silica and polydopamine. The unique core-shell structure not only improves the drug loading of the magnetic nanomaterials, but also produces high photothermal conversion efficiency. Furthermore, the reducibility of polydopamine was found to be able to reduce Fe 3+ to Fe 2+ and thus promote the production of hydroxyl radicals that can kill the tumor cells based on the Fenton reaction. The magnetic nanomaterials are capable of simultaneously combining photothermal and chemodynamic therapy and permit the efficient treatment for tumors in the future.

Color tuning and energy transfer in Eu2+/Mn2+-doped Ba3Y(PO4)3 eulytite-type orthophosphate phosphors.