No abstract

It is of great significance to design a multifunctional nanotherapeutic agent with flexible and intelligent response performance for a tumor microenvironment. Herein, hollow-structured hCu2–x S@Au derivatives were synthesized for multiswitchable drug release and synergistic photothermal therapy/chemotherapy. The remarkably improved release ratio (over 90%) under higher glutathione concentration and lower pH conditions could be ascribed to the fracture of the disulfide bond and the reduction of force between the drug and nanovehicles. In addition, the shrinking of tetradecanol molecules anchored on the surface of hCu2–x S@Au by near-infrared (NIR) photo-activation could also enhance the release of drugs in the cavity of hCu2–x S@Au. After decorating with Au nanoparticles, the favorable electron transitions endowed hCu2–x S@Au nanoparticles with a high photothermal conversion efficiency, which reaches 36.4% under a NIR laser irradiation of 808 nm. Compared to conventional single/double stimuli-responsive delivery, the proposed multimodal release pattern powerfully overcomes the limitation of insufficient dose as a single/double release unit for a tumor microenvironment was unable to meet the release requirements. After phagocytosis by tumor cells, the continuous release of anticancer drugs facilitated a substantial improvement in the antitumor therapy efficacy by combining chemo- and photothermal therapy in vivo. This design platform can provide a promising strategy for continuous and synergistic tumor therapy.

A nickel monosubstituted polyoxometalate (POM)/polyaniline organic–inorganic hybrid SiW 11 Ni/PANI was synthesized using the liquid-phase method at room temperature to achieve the solidification of water-soluble POMs. The SiW 11 Ni/PANI hybrid was characterized by scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, and zeta potential. On the basis of π–π stacking and affinity interaction between the SiW 11 Ni/PANI hybrid and proteins, the SiW 11 Ni/PANI hybrid showed good adsorption selectivity to hemoglobin (Hb). At pH 7.0, 0.5 mg of SiW 11 Ni/PANI resulted in an adsorption efficiency of 92.4% for 1 mL of 100 μg mL –1 Hb. The adsorption behavior of Hb on the surface of the hybrid fitted with the Langmuir model, and the maximum adsorption capacity was 692 mg g –1 . The adsorbed Hb was eluted by BR (0.04 mol L –1 , pH 9), providing a recovery of 94%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis assay results indicated that the Hb in human whole blood could selectively be adsorbed by the SiW 11 Ni/PANI hybrid, and the obtained Hb was with high purity. It could expand the application of POMs in life science due to the application of the POM hybrid in protein isolation/purification.