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Microspheric and lamellar BiVO(4) powders were selectively prepared through a hydrothermal process by using cetyltrimethylammonium bromide (CTAB) as a template-directing reagent. The as-prepared BiVO(4) powders were characterized by X-ray diffraction, electron microscopy, nitrogen adsorption-desorption experimentation, Fourier transform infrared spectrometry, and UV-vis diffuse reflectance spectroscopy. Experimental results indicate that microspheric BiVO(4) with particle sizes in the range of 7-12 microm can be derived from a relatively low hydrothermal temperature (

The design of new functional materials with excellent hydrogen production activity under visible‐light irradiation has critical significance for solving the energy crisis. A well‐controlled synthesis strategy is developed to prepare an Au–Pt–CdS hetero‐nanostructure, in which each component of Au, Pt, and CdS has direct contact with the other two materials; Pt is on the tips and a CdS layer along the sides of an Au nanotriangle (NT), which exhibits excellent photocatalytic activity for hydrogen production under light irradiation (λ > 420 nm). The sequential growth and surfactant‐dependent deposition produce the three‐component Au–Pt–CdS hybrids with the Au NT acting as core while Pt and CdS serve as a co‐shell. Due to the presence of the Au NT cores, the Au–Pt–CdS nanostructures possess highly enhanced light‐harvesting and strong local‐electric‐field enhancement. Moreover, the intimate and multi‐interface contact generates multiple electron‐transfer pathways (Au to CdS, CdS to Pt and Au to Pt) which guide photoexcited electrons to the co‐catalyst Pt for an efficient hydrogen reduction reaction. By evaluating the hydrogen production rate when aqueous Na2SO3–Na2S solution is used as sacrificial agent, the Au–Pt–CdS hybrid exhibits excellent photocatalytic activity that is about 2.5 and 1.4 times larger than those of CdS/Pt and Au@CdS/Pt, respectively.

Lung cancer (LC) with its different subtypes is generally known as a therapy resistant cancer with the highest morbidity rate worldwide. Therapy resistance of a tumor is thought to be related to cancer stem cells (CSCs) within the tumors. There have been indications that the lung cancer is propagated and maintained by a small population of CSCs. To study this question we established a panel of 15 primary lung cancer cell lines (PLCCLs) from 20 fresh primary tumors using a robust serum-free culture system. We subsequently focused on identification of lung CSCs by studying these cell lines derived from 4 representative lung cancer subtypes such as small cell lung cancer (SCLC), large cell carcinoma (LCC), squamous cell carcinoma (SCC) and adenocarcinoma (AC). We identified a small population of cells strongly positive for CD44 (CD44high) and a main population which was either weakly positive or negative for CD44 (CD44low/−). Co-expression of CD90 further narrowed down the putative stem cell population in PLCCLs from SCLC and LCC as spheroid-forming cells were mainly found within the CD44highCD90+ sub-population. Moreover, these CD44highCD90+ cells revealed mesenchymal morphology, increased expression of mesenchymal markers N-Cadherin and Vimentin, increased mRNA levels of the embryonic stem cell related genes Nanog and Oct4 and increased resistance to irradiation compared to other sub-populations studied, suggesting the CD44highCD90+ population a good candidate for the lung CSCs. Both CD44highCD90+ and CD44highCD90− cells in the PLCCL derived from SCC formed spheroids, whereas the CD44low/− cells were lacking this potential. These results indicate that CD44highCD90+ sub-population may represent CSCs in SCLC and LCC, whereas in SCC lung cancer subtype, CSC potentials were found within the CD44high sub-population.

The properties of a new photosensitizer, meso-tetra-hydroxyphenyl-chlorin (mTHPC), were studied using V79 cells (Chinese-hamster lung fibroblasts). Comparisons were made with 2 other photosensitizers: photofrin II (PII) and meso-tetra-hydroxyphenyl-porphyrin (mTHPP). A main advantage of mTHPC is that it has a strong absorption at 652 nm. Maximal cellular uptake of the dye was observed after 24 hr incubation of the cells with the drug. Using a confocal laser-scanning fluorescence microscope, we observed a diffuse distribution of mTHPC in the cytoplasm. Furthermore, the lipophilicity of mTHPC was compared with that of the components of PII by means of high-pressure liquid chromatography (HPLC). Absorption and fluorescence spectroscopy indicated that aggregated as well as monomeric mTHPC was bound to the cells. The action spectrum for photo-inactivation of the cells showed that aggregated mTHPC did not contribute significantly to its photosensitizing effects. In the present cellular system, the efficiency of photodynamic therapy (PDT) with mTHPC (cells were irradiated at a wavelength of 652 nm) was higher than with PII (irradiation at 630 nm) or with mTHPP (648 nm). The quantum yield for photo-inactivation of cells was smaller for mTHPC than for mTHPP and PII. The addition of 1,3-diphenylisobenzofuran (DPBF) reduced cell inactivation during PDT. Thus, PDT with mTHPC seems to act at least partly via a type-II process.