Amino modified nanofibers anchored to Prussian blue nanoparticles selectively remove Cs+ from water.

To improve the selective separation performance of silica nanofibers (SiO2 NFs) for cesium ions (Cs+) and overcome the defects of Prussian blue nanoparticles (PB NPs), PB/SiO2-NH2 NFs were prepared to remove Cs+ from water. Among them, 3-aminopropyltriethoxysilane (APTES) underwent an alkylation reaction with SiO2, resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO2 NFs. Meanwhile, the amino functional groups in APTES combined with Fe3+ and then reacted with Fe2+ to form PB NPs, which anchored firmly on the aminoated SiO2 NFs surface. In our experiment, the maximum adsorption capacity of PB/SiO2-NH2 NFs was 111.38 mg/g, which was 31.5 mg/g higher than that of SiO2 NFs. At the same time, after the fifth cycle, the removal rate of Cs+ by PB/SiO2-NH2 NFs adsorbent was 75.36% ± 3.69%. In addition, the adsorption isotherms and adsorption kinetics of PB/SiO2-NH2 NFs were combined with the Freundlich model and the quasi-two-stage fitting model, respectively. Further mechanism analysis showed that the bond between PB/SiO2-NH2 NFs and Cs+ was mainly a synergistic action of ion exchange, electrostatic adsorption and membrane separation.

Polyoxometalate-Based Organic-Inorganic Hybrids as Antitumor Drugs.

Polyoxometalates (POMs) have shown encouraging antitumor activity. However, their cytotoxicity in normal cells and unspecific interactions with biomolecules are two major obstacles that impede the practical applications of POMs in clinical cancer treatment. Derivatization of POMs with more biocompatible organic ligands is expected to cause a synergetic effect and achieve improved bioactivity and biospecificity. Herein, the synthesis of an amphiphilic organic-inorganic hybrid is reported by grafting a long-chain organoalkoxysilane lipid onto a POM. The amphiphilic POM hybrid could spontaneously assemble into the vesicles and exhibits enhanced antitumor activity for human colorectal cancer cell lines (HT29) compared to that of parent POMs. This detailed study reveals that the amphiphilic nature of POM hybrids enables the as-formed vesicles to easily bind to the cell membranes and then be uptaken by the cells, thus leading to a substantial increase in antitumor activity. Such prominent antitumor action is mostly accomplished via cell apoptosis, which ultimately results in cell death. Our finding demonstrates that novel POM hybrids-based drugs with increased bioactivity could be obtained by decorating POMs with selective organic ligands.

Synthesis of Heteromorphic Bi2WO6 Films With an Interpenetrate 1D/2D Network Structure for Efficient and Stable Photocatalytic Degradation of VOCs.

2D layered Bi2WO6 (BWO) is a widely used attractive photocatalyst for degrading VOCs, but the low visible-light utilization and the easy stacking 2D nanosheets (NSs) limit photocatalysis efficiency and stability. Here, inspired by Eucalyptus, a synergistic strategy of multiscale domain-confinement and electrostatic force action, based on electrospinning is proposed, for fabricating a heteromorphic BWO photocatalyst. It is found that BWO NSs can grow radially in an orderly spaced arrangement along BWO nanofibers (NFs) during sintering, thereby forming 1D/2D BWO junctions like eucalyptus leaves. This interpenetrating 1D/2D network structure not only solves the easy stacking problem of BWO NSs but also selectively exposes the {010} crystal planes that exhibit efficient hole oxidation. In addition, this peculiar structure enriches electrons at the 1D/2D interface to avoid carrier recombination, thus improving the photocatalytic activity. The photocatalyst material with a reduced bandgap width from 2.56 to 2.49 eV can rapidly degrade 100% of acetaldehyde under visible light without using sacrificial agents and photosensitizers and shows superior stability for eight cycles without any decay. This study provides a feasible method to synthesize an efficient and stable BWO photocatalyst.

Cysteine-modified orange peel for removal of Cu(II) from aqueous solutions.

In the present work, cysteine-modified orange peel (COP) for the removal of Cu(II) from aqueous solutions has been developed and comparatively studied with diethylenetriamine-modified orange peel (DOP). Both COP and DOP were systematically evaluated via their capabilities for adsorbing Cu(II), including the key influential parameters such as initial pH, contact time and initial Cu(II) concentration. Further studies suggest that the sorption of Cu(II) onto both COP and DOP fits well with the pseudo-second-order equation, and the corresponding sorption isotherm can be classified to a Langmuir isotherm model. COP appears more advantageous over DOP and far better than that of unmodified OP in removal of Cu(II) from aqueous system. The maximum capacities of COP and DOP for adsorbing Cu(II) are 95.23 and 83.68 mg/g, respectively, about three times higher than that of unmodified OP. The sorption efficiency of COP drops by merely about 3% after five cycles, implying a promising usage in the removal of Cu(II) from wastewater in practice.

Submicrometer organic silica gel fiber for oxygen sensing.

We introduce the electrospinning method into fabricating oxygen-sensitive submicrometer scale optical fiber. Uniform tris (4,7-diphenyl-1,10-phenathroline) ruthenium(II) dichloride ([Ru(dpp)(3)](2+)Cl(2))-doped fibers with a diameter of 900 nm are obtained by electrospinning the organic silicon sol solution derived from tetraethyl orthosilicate and n-Octyltriethoxysilane (C(14)H(32)O(3)Si). The experimental results show that the single gel fiber exhibits excellent optical and sensing properties. A laser with a wavelength of 452 nm can be efficiently launched into the fiber and guide along the fiber to excite the fluorescence. Then, we find that [Ru(dpp)(3)](2+)-gel fiber has favorable optical and sensing characteristics, and the Stern-Volmer plots are linear in the full concentration range of O(2) (0-100 vol. %). The ratio of I(0)/I(100), where I(0) and I(100) respectively represent the fluorescence intensities of the fiber exposed to 100% N(2) and 100% O(2), as the sensitivity of the fiber is 3.5. Simultaneously, the fiber can make a quick response within 100 ms. This method provides an effective and convenient way to fabricate highly uniform nanoscale or microscale optical waveguides for photonic devices.

Effect of groundwater geochemistry on pentachlorophenol remediation by smectite-templated nanosized Pd0/Fe0.

Zero-valent iron holds great promise in treating groundwater, and its reactivity and efficacy depend on many surrounding factors. In the present work, the effects of solution chemistry such as pH, humic acid (HA), and inorganic ions on pentachlorophenol (PCP) dechlorination by smectite-templated Pd(0)/Fe(0) were systematically studied. Smectite-templated Pd(0)/Fe(0) was prepared by saturating the negatively charged sites of smectite clay with Fe(III) and a small amount of Pd(II), followed by borohydride reduction to convert Fe(III) and Pd(II) into zero-valent metal clusters. Batch experiments were conducted to investigate the effects of water chemistry on PCP remediation. The PCP dechlorination rate critically depends on the reaction pH over the range 6.0~10.0; the rate constant (k (obs)) increases with decreasing the reaction pH value. Also, the PCP remediation is inhibited by HA, which can be attributed to the electron competition of HA with H(+). In addition, the reduction of PCP can be accelerated by various anions, following the order: Cl(-) > HCO (3) (-) > SO (4) (2-) ~no anion. In the case of cations, Ca(2+) and Mg(2+) (10 mM) decrease the dechlorination rate to 0.7959 and 0.7798 from 1.315 h(-1), respectively. After introducing HA into the reaction systems with cations or/and anions, the dechlorination rates are similar to that containing HA alone. This study reveals that low pH and the presence of some anions such as Cl(-) facilitate the PCP dechlorination and induce the rapid consumption of nanosized zero-valent iron simultaneously. However, the dechlorination rate is no longer correlated to the inhibitory or accelerating effects by cations and anions in the presence of 10 mg/L HA.

Stabilized liposomal nanohybrid cerasomes for drug delivery applications.

Paclitaxel loaded cerasomes exhibited sophisticated controlled release behavior and remarkably high stability towards surfactant solubilization, long-term storage, acidic treatment, and all factors susceptible to destabilize conventional liposomes, demonstrating that liposomal nanohybrid cerasomes can be a new promising drug delivery system.