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A versatile strategy to fabricate newly-developed silica-modified membranes based on organic/inorganic hybridization for oil/water separation is described in this study. The modified membranes are easily obtained by a simple two-step immersion of polysulfone hollow fiber membranes with radial gradient microstructure (RGM-PSF) into a silicon solution of tetraethyl orthosilicate (TEOS) mixed with 3-glycidyloxypropyltrimethoxysilane (GOPTS) and subsequently into a lactic acid solution. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM) were utilized to characterize the surface compositions and microstructures. A micro/nano-scaled SiO2-based coating was generated roughly and continuously on the membrane surfaces, endowing them with superhydrophilicity and underwater superoleophobicity. Results of dead-end filtration experiments demonstrated that the hybridized RGM-PSF membranes could be applied in oil-in-water emulsion separation far more efficiently, with higher water permeate flux, better oil rejection ratio, and higher pressure endurance than those of the common ones. Therefore, this study has provided a facile approach to prepare silica-modified membranes with special wettability, showing prominent application prospects for oily wastewater treatment in practical processes.

Posterior capsular opacification is the most frequent complication after cataract surgery, which is induced by the proliferation, differentiation and migration of lens epithelial cells. Inhibiting the proliferation of human lens epithelial cells could reduce the occurrence of posterior capsular opacification. To explore the possible potential of ZnO nanoparticles in treating posterior capsular opacification, we investigated the effect of ZnO nanoparticles on the human lens epithelial cell proliferation in the presence and absence of ultraviolet B (UVB) irradiation via 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. The results indicate that ZnO nanoparticles could apparently inhibit the proliferation of human lens epithelial cells in a dose-dependent manner, and UVB irradiation can further enhance this inhibitory role for the human lens epithelial cell proliferation, indicating the great potential of ZnO nanoparticles in treating posterior capsular opacification in clinical application.

Objectives As a parenchymal cell, the photoreceptor is more susceptible to alterations in outer micro-environmental conditions than other cells. In the present study, we aimed to investigate inhibitory effects of zinc oxide (ZnO) nanoparticles on expression of manganese superoxide dismutase (MnSOD) in murine photoreceptor-derived cells. Materials and methods We investigated effects of ZnO nanoparticles on murine photoreceptor cell viability and on expression and activity of MnSOD using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, immunofluorescence analysis, flow cytometry, quantitative real-time PCR and enzyme-linked immunosorbent assay (ELISA). Results ZnO nanoparticles were found to have higher cytotoxic effects in concentration- and time-dependent manners, to elevate intracellular levels of hydrogen peroxide and hydroxyl radicals, and thus to induce overproduction of reactive oxygen species (ROS) and collapse of mitochondrial membrane potential, leading to cell damage. Moreover, ZnO nanoparticles also significantly reduced expression of MnSOD at both the mRNA and protein levels, reduced its activity, and further aggravated oxidative stress-mediated cell damage. Conclusion Overall, ZnO nanoparticle-induced cytotoxicity was associated with elevated levels of oxidative stress due to overproduction of ROS and reduced expression and activity of MnSOD.

Two novel chiral thiophosphoramides and two chiral phosphoramidites were synthesized starting from (S)-α-phenylethylamine and (R)-(+) or (S)-(−)-1,1′-Bi-2-naphthol (BINOL), respectively, and their application in combination with Lewis acid as cocatalysts in asymmetric Morita–Baylis–Hillman (MBH) reaction was investigated. Dramatic rate acceleration (the corresponding adducts were obtained in fair to excellent chemical yield within 15 min–5 h) was observed in these chiral phosphorus reagents/Lewis acid cocatalyzed MBH reaction between 4-nitrobenzaldehyde and activated alkenes, and in one case, moderate enantioselectivity was achieved (the corresponding adduct's ee value is 44%).

Asymmetric Michael-type Friedel–Crafts (F–C) alkylations of indoles with nitroolefins catalyzed by a chiral H8-BINOL-based phosphoric acid were investigated. The reactions took place very smoothly in the presence of only 5 mol-% of catalyst at room temperature to afford the desired F–C alkylation products in good yields and with moderate enantioselectivities. GRAPHICAL ABSTRACT