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Conventional photosensitizer-based photodynamic therapy is triggered by UV-light irradiation and depends on oxygen. However, it is hard to be applied to the deep and hypoxic tumor. To address this issue, we reported a new kind of g-C3N4 nanosheet decorated with gold nanoparticles (AuNPs), which could generate a high amount of reactive oxygen species (ROS) under a 670 nm laser irradiation in an oxygen-free environment. This synthesized semiconductor-metal heterojunction served as a superior photodynamic agent, showing prominent cancer cell-killing and tumor growth-suppressing effects in the presence of a 670 nm light and g-C3N4-AuNP composites, and its excellent ROS generation property was also validated by further bactericidal experiment.

Mercury species have aroused wide concern in the past several decades due to their high toxicity. However, it is still difficult to detect ultra-trace mercury species due to their biochemical transformation in complex samples. To establish a simpler and more sensitive method for pre-concentration and determination of trace mercury species, molybdenum disulfide (MoS2) nanosheets with sulfur-rich characteristics and enlarged interlayer spacing were prepared by a hydrothermal method coupled with a sonication-assisted liquid exfoliation method and acted as solid-phase extraction adsorbent. The nano-MoS2 had high adsorption capacity, fast adsorption rate and excellent selectivity towards mercury ions (Hg2+), methyl mercury (MeHg+) and ethyl mercury (EtHg+) in a wide pH range and complex matrices. And it could be easily regenerated by 4 mol L−1 HCl and reused several times. After optimizing HPLC-UV-HG-AFS conditions, a great linearity (1.0–10.0 μg L−1, R2 = 0.999 for Hg2+, MeHg+ and EtHg+), lower detection limits (0.017, 0.037 and 0.021 ng mL−1 for Hg2+, MeHg+ and EtHg+, respectively), relative standard deviations (

Clinically approved photodynamic therapy (PDT) has emerged as an alternative treatment for cancers and malignant diseases; however, high quality PDT agents were still in great demand. Herein, the van der Waals (vdW) heterostructure of graphitic carbon nitride (g-C3N4, abbreviated as CN here) and metallic molybdenum disulfide (1T-MoS2, abbreviated as MS here) was fabricated, PEGylated, and then investigated. By making use of the extraordinary antenna effect and the ultrafast electron transfer rate of metallic molybdenum disulfide, as well as the efficient separation of photogenerated electron-hole pairs of the final heterojunction, massive reactive oxygen species (ROS) can be generated under 670 nm laser irradiation together with the as-synthesized g-C3N4@1T-MoS2 vdW nanostructure (CNMS), which should be largely owed to the appealing photocatalytic water splitting property of the CNMS structure. It was well proved by the in vitro studies that the intracellularly produced ROS can result in cell death, by the way of inducing cell apoptosis and/or necrosis through mediating phosphatidylserine ectropion, mitochondrial depolarization, and chromosomal DNA fragmentation, as well as up-regulating the expression of apoptosis-related proteins and unbalancing intracellular redox homeostasis. In vivo exploration also gave out satisfactory results that the tumor growth could be significantly inhibited by the photodynamic therapy. Additionally, outstanding biocompatibility and biosafety were also guaranteed. All these results provided compelling evidences for that the CNMS vdW heterostructure is an aussichtsreich nano-photosensitizer, and may provide some fresh ideas for the developing of nanomedicine for PDT application.

Fabricating efficient materials for environmental purposes is a priority and the subject of much attention nowadays. The objectives of this study are to adopt an amino modification approach to improve the selective removal capacity of magnetic graphene oxide (MGO) for Cu(II) ions, and explore how it performs in single and binary systems by taking Cd(II) as a comparison. After grafting the amino groups, the final material exhibited promoted capacities for Cu(II) and Cd(II), and a more apparent selective adsorption process can be observed. The maximum equilibrium adsorbances of amino modified MGO were 578.1 mg g−1 for Cu(II) and 184.7 mg g−1 for Cd(II) under our experimental conditions, compared with 319.1 mg g−1 and 161.2 mg g−1 of MGO for Cu(II) and Cd(II), respectively. Characterization results and experiment data confirmed that the introduction of N species contributed to the enhancement. This may pave the way for better understanding of the underlying mechanism, and provide inspiration for synthesizing new adsorbents.

We developed dual biologically responsive nanogapped gold nanoparticle vesicles loaded with immune inhibitor and carrying an anticancer polymeric prodrug for synergistic concurrent chemo-immunotherapy against primary and metastatic tumors, along with guided cargo release by photoacoustic (PA) imaging in the second near-infrared (NIR-II) window. The responsive vesicle was prepared by self-assembly of nanogapped gold nanoparticles (AuNNPs) grafted with poly(ethylene glycol) (PEG) and dual pH/GSH-responsive polyprodug poly(SN38-co-4-vinylpyridine) (termed AuNNP@PEG/PSN38VP), showing intense PA signal in the NIR-II window. The effect of the rigidity of hydrophobic polymer PSN38VP on the assembled structures and the formation mechanism of AuNNP@SN38 Ve were elucidated by computational simulations. The immune inhibitor BLZ-945 was encapsulated into the vesicles, resulting in pH-responsive release of BLZ-945 for targeted immunotherapy, followed by the dissociation of the vesicles into single AuNNP@PEG/PSN38VP. The hydrophilic AuNNP@PEG/PSN38VP nanoparticles could penetrate deep into the tumor tissues and release the anticancer drug SN38 under the reductive environment. A PA signal in the NIR-II window in the deep tumor region was obtained. The BLZ-945-loaded vesicle enabled enhanced PA imaging-guided concurrent chemo-immunotherapy efficacy, inhibiting the growth of both primary tumors and metastatic tumors.

Conventional photosensitizer-based photodynamic therapy is triggered by UV-light irradiation and depends on oxygen. However, it is hard to be applied to the deep and hypoxic tumor. To address this issue, we reported a new kind of g-C

An untargeted metabolomics study to investigate the metabolome change in plasma, hippocampus and prefrontal cortex (PFC) in an animal model with a major depressive disorder (MDD) had been conducted. Metabolomic profiling for the different bio-samples was analyzed by using Ultra-High Performance Liquid Chromatography coupled with Orbitrap mass spectrometry (UPLC-Orbitrap-MS). Behavioral tests were applied to evaluate the depressive degree and antidepressive effect. Then univariate and multivariate statistics including Student's t-test, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied to reveal the metabolic differences between the control, model and antidepressive-treated groups. Metabolomics analysis demonstrated that MDD was a kind of systemic disease in which disturbance of neuroendocrinology, amino acid metabolism, energy metabolism, lipid metabolism and synthesis of neurotransmitters were involved. The significantly changed metabolites acquired from the statistical method were identified and a simplified panel which consisted of 6 metabolites including L-tryptophan, L-kynurenine, quinolinic acid, L-phenylalanine, gamma-aminobutyric acid and N-acetylaspartic acid was obtained. In combination with the results of the sucrose preference test, a new PLS-DA model conducted by the identified changed metabolome showed a good predictive power which meant the metabolome was able to rank the depressive level as the behavioral test. Then correlational analysis indicated the simplified panel in plasma had a relative good correlation with that in hippocampus and PFC. This study offers a new strategy for characterization of endogenous metabolic perturbations by a metabolomics method and the good predictive power and correlation for the significantly changed metabolome between plasma and brain regions which might be helpful in ranking the depressive level in the CUMS model. These results are helpful in the further study to develop a noninvasive and exact diagnostic approach by an objective laboratory-based test through the metabolomics platform.

Mercury species have aroused wide concern in the past several decades due to their high toxicity. However, it is still difficult to detect ultra-trace mercury species due to their biochemical transformation in complex samples. To establish a simpler and more sensitive method for pre-concentration and determination of trace mercury species, molybdenum disulfide (MoS

A novel magnetic surface ion-imprinted polymer was developed by copolymerization of magnetic multi-walled carbon nanotubes as the core, 3-aminopropyltriethoxysilane (APTES) as the functional monomer and tetraethoxysilane (TEOS) as the cross-linker with chelating complexes of Cd(II). The Cd(II)-imprinted polymer was characterized by FT-IR spectroscopy, scanning electron microscopy (SEM) and a batch procedure. Under the optimized conditions, the maximum adsorption of Cd(II) was 27.90 mg g−1 and the adsorption time was 70 min. The imprinted polymer showed higher selectivity for Cd(II) in comparison of the competitive adsorptions of Cd(II), Zn(II) and Cu(II) to the non-imprinted polymer. Relative selectivity factor (k′) values of Cd(II)/Zn(II) and Cd(II)/Cu(II) were 15.44 and 14.32, respectively. The new Cd(II)-imprinted polymer has been tested and applied for the separation and concentration of Cd(II) in tap water, with high recoveries ranging from 103.8% to 108.8%.

Smart assemblies have attracted increased interest in various areas, especially in developing novel stimuli-responsive theranostics. Herein, commercially available, natural tannic acid (TA) and iron oxide nanoparticles (Fe3 O4 NPs) are utilized as models to construct smart magnetic assemblies based on polyphenol-inspired NPs-phenolic self-assembly between NPs and TA. Interestingly, the magnetic assemblies can be specially disassembled by adenosine triphosphate, which shows a stronger affinity to Fe3 O4 NPs than that of TA and partly replaces the surface coordinated TA. The disassembly can further be facilitated by the acidic environment hence causing the remarkable change of the transverse relaxivity and potent "turn-on" of fluorescence (FL) signals. Therefore, the assemblies for specific and sensitive tumor magnetic resonance and FL dual-modal imaging and photothermal therapy after intravenous injection of the assemblies are successfully employed. This work not only provides understandings on the self-assembly between NPs and polyphenols, but also will open new insights for facilely constructing versatile assemblies and extending their biomedical applications.