Mo2C is an excellent photoactive material that can trigger hyperthermia and ROS generation, thus contributing to synergistic photothermal/photodynamic outcomes. Moreover, Mo2C is a potential photoacoustic and CT contrast agent.
13 January 2021 in Journal of Materials Chemistry C
Optically transparent Eu3+-doped Pb(Mg1/3Nb2/3)O3–0.25PbTiO3 (PMN–0.25PT:Eu3+) relaxor ferroelectric ceramics with high piezoelectricity were prepared by oxygen-atmosphere sintering followed by hot-press sintering.
Employing near infrared (NIR) light for photocatalytic reactions is preferable, considering effective solar utilization. Herein, the metalloid of tungsten carbide (WC) was used as an NIR-driven photocatalyst for the photodegradation of organic pollutants for the first time. The noble metal-like electronic properties of WC were proven via the analysis of its electronic occupied state using ultraviolet photoelectron spectroscopy and valence band XPS. In addition, both the experimental evidence and 3D finite element simulation revealed the NIR-responsive localized surface plasmon resonance (LSPR) behavior of the WC nanoparticles. Accordingly, the WC nanoparticles exhibited excellent UV-visible-NIR full-spectrum absorption, high NIR-triggered photocurrent response and resultant NIR-driven photocatalytic degradation performance. The NIR-mediated photocatalytic mechanism of WC was proposed based on a radical scavenging test, fluorescence observation of radical generation and spin-trapping electron paramagnetic resonance measurements. Hence, metallic WC with NIR absorption and photocatalytic activity may pave the way for the design of full-solar-spectrum-responsive photocatalysts.
22 April 2016 in Journal of Experimental & Clinical Cancer Research
Hepatocellular carcinoma (HCC) accounts for 75 % of liver cancers and is the second most lethal cancer, associated with its multiple etiologies, poor prognosis and resistance to chemotherapy drugs. Chemotherapy treatment on HCC suffers low efficacy of drug uptake and can produce a range of side effects. Here we report an investigation on the effect of a combined treatment on human hepatocellular carcinoma BEL-7402 cells using low-intensity ultrasound (US) and 5-fluorouracil (5-FU). The uptake of 5-FU was measured by the high-performance liquid chromatography (HPLC). DNA damage was detected by the comet assay. MTT assay was used to examine cell viability. Intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (Δψm) were respectively detected by the fluorescent probes DCFH-DA or JC-1. Endogenous apoptosis-associated proteins were analyzed by the western blot and immunohistochemistry. Histopathological changes were evaluated by the hematoxylin and eosin (H&E) staining. Cell apoptosis was evaluated by the TUNEL and flow cytometry assays. Cell proliferation was measured using the immunohistochemical staining of PCNA. Our results showed that low-intensity US (1.1 MHz, 1.0 W/cm2, 10 % duty cycle) significantly enhanced the uptake of 5-FU, 5-FU-mediated DNA damage and reactive oxygen species (ROS) generation. The increased ROS production up-regulated the p53 protein level, which led to the up-regulation of Bax and down-regulation of Bcl-2. The enhancement of ROS generation and the activation of the apoptosis-associated proteins further triggered the collapse of mitochondrial membrane potential, released cytochrome c from mitochondria into cytosol and activated the mitochondria-caspase pathway, and cell apoptosis. Such enhanced effects could be partially blocked by the ROS scavenger N-acetylcysteine (NAC). Overall, low-intensity US combined with 5-FU led to an effective inhibition of tumor growth and prolonged overall survival of BEL-7402 HCC-bearing nude mice by more than 15 % compared with 5-FU treatment alone. Our results showed that low-intensity ultrasound combined with 5-FU produced much enhanced synergistic anti-tumor effects via enhanced ROS production in treating HCC.
In this work, the highly oriented CdS-coated-ZnO nanorod arrays have been fabricated. The CdS-coated-ZnO nanorod arrays show high electrochemiluminescence intensity, fast response and good stability. All of the desirable properties spur the development of an ECL immunosensor for the detection of the liver cancer cell line (HepG2 cells). Two successive modification steps of 3-aminopropyltriethoxysilane and gold nanoparticles onto the CdS-coated-ZnO nanorod arrays not only offer the substrates for conjugation of antibody, but also effectively enhance the ECL signal, resulting in production of the high performance ECL immunosensor. The ECL immunosensor exhibits a sensitive response to HepG2 cells in a linear range of 300–10 000 cells mL−1 with a detection limit of 256 cells mL−1. The proposed sensor characteristics of high specificity, good reproducibility and remarkable stability will provide a sensitive, selective, and convenient approach for the clinical detection of cancer cells.
30 May 2018 in Physical Chemistry Chemical Physics
A WO3−x/TiO2−x nanotube array (NTA) heterojunction photoanode was strategically designed to improve photoelectrocatalytic (PEC) performance by establishing a synergistic vacancy-induced self-doping effect and localized surface plasmon resonance (LSPR) effect of metalloid non-stoichiometric tungsten suboxide. The WO3−x/TiO2−x NTA heterojunction photoanode was synthesized through a successive process of anodic oxidation to form TiO2 nanotube arrays, magnetron sputtering to deposit metalloid WO3−x, and post-hydrogen reduction to engender oxygen vacancy in TiO2−x as well as crystallization. On the merits of such a synergistic effect, WO3−x/TiO2−x shows higher light-harvesting ability, stronger photocurrent response, and resultant improved photoelectrocatalytic performance than the contrast of WO3−x/TiO2, WO3/TiO2 and TiO2, confirming the importance of oxygen vacancies in improving PEC performance. Theoretical calculation based on density functional theory was applied to investigate the electronic structural features of samples and reveal how the oxygen vacancy determines the optical property. The carrier density tuning mechanism and charge transfer model were considered to be associated with the synergistic effect of self-doping and metalloid LSPR effect in the WO3−x/TiO2−x NTA.