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Type I photodynamic therapy (PDT) with less oxygen consumption shows great potential to overcome the malignant hypoxia in solid tumors. Herein, a novel meso phosphate-substituted pyronin PY-P and its nanoparticles (PY-P NPs) were prepared as an efficient type I organic photosensitizer. The

Achieving CO oxidation at room temperature is significant for gas purification but still challenging nowadays. Pt promoted by 3d transition metals (TMs) is a promising candidate for this reaction, but TMs are prone to be deeply oxidized in an oxygen-rich atmosphere, leading to low activity. Herein we report a unique structure design of graphene-isolated Pt from CoNi nanoparticles (PtǀCoNi) for efficiently catalytic CO oxidation in an oxygen-rich atmosphere. CoNi alloy is protected by ultrathin graphene shell from oxidation and therefore modulates the electronic property of Pt-graphene interface via electron penetration effect. This catalyst can achieve near 100% CO conversion at room temperature, while there are limited conversions over Pt/C and Pt/CoNiOx catalysts. Experiments and theoretical calculations indicate that CO will saturate Pt sites, but O2 can adsorb at the Pt-graphene interface without competing with CO, which facilitate the O2 activation and the subsequent surface reaction. This graphene-isolated system is distinct from the classical metal-metal oxide interface for catalysis, and it provides a new thought for the design of heterogeneous catalysts., Achieving CO oxidation at room temperature is significant for gas purification but remains challenging to perform. Here, the authors report design of graphene-isolated Pt from cobalt-nickel nanoparticles for efficiently catalytic CO oxidation in an oxygen-rich atmosphere.

This manuscript reports a strategy for controlling the crystallization kinetics and improving the quality of engineered self-assembled 3D DNA crystals. Growing large, high-quality biomacromolecule crystals is critically important for determining the 3D structures of biomacromolecules. It often presents a great challenge to structural biologists. Herein, we introduce a rationally designed agent to modulate the crystallization process. Under such conditions, fewer, but larger, crystals that yield diffraction patterns of modestly higher resolution are produced compared with the crystals from conditions without the modulating agent. We attribute the improvement to a smaller number of nuclei and slow growth rate of crystallization. This strategy is expected to be generally applicable for crystallization of other biomacromolecules.

Synthetic single crystals are usually homogeneous solids. Biogenic single crystals, however, can incorporate biomacromolecules and become inhomogeneous solids so that their properties are also extrinsically regulated by the incorporated materials. The discrepancy between the properties of synthetic and biogenic single crystals leads to the idea to modify the internal structure of synthetic crystals to achieve nonintrinsic properties by incorporation of foreign material. Intrinsically colorless and diamagnetic calcite single crystals are turned into colored and paramagnetic solids, through incorporation of Au and Fe3O4 nanoparticles without significantly disrupting the crystalline lattice of calcite. The crystals incorporate the nanoparticles and gel fibers when grown in agarose gel media containing the nanoparticles, whereas the solution-grown crystals do not. As such, our work extends the long-history gel method for crystallization into a platform to functionalize single-crystalline materials.

Supported nanocrystalline titanium dioxide (TiO2) has been prepared by a post-synthesis step via Ti-alkoxide hydrolysis through the use of mesoporous SBA-15 silica. TiO2/SBA-15 composites with various TiO2 loading have been prepared and characterized by X-ray diffraction, nitrogen adsorption, Fourier transform infrared spectroscopy and diffusive reflective UV-vis spectroscopy. The addition of mesoporous SBA-15 prevents the anatase to rutile phase transformation and the growth of crystal grain. TiO2 did not block the SBA-15 pores, and their surface was fully accessible for nitrogen adsorption. Calcination in air of the composites up to 800 degrees C did not change the nanocrystal phase and slightly increased the domain size from 5.0 to 7.5 nm, indicating that the anatase TiO2 grains in the mesostructures have a relatively high thermal stability and proper pore diameter allows controlling the size of obtained titania particles. The TiO2/SBA-15 composites prepared by this study showed much higher photodegradation ability for methylene blue (MB) than commercial pure TiO2 nanoparticles P-25. Experimental results indicate that the photocatalytic activity of titania/silica mixed materials depends on the adsorption ability of composite and the photocatalytic activity of the titania, and there is an optimal ratio of Ti:Si, too high or low Ti:Si ratio will lower the photodegradation ability of the composites.

Phenols are well known noxious compounds, which are often found in various water sources. A novel analytical method has been researched and developed based on the properties of hemin-graphene hybrid nanosheets (H-GNs). These nanosheets were synthesized using a wet-chemical method, and they have peroxidase-like activity. Also, in the presence of H2O2, the nanosheets are efficient catalysts for the oxidation of the substrate, 4-aminoantipine (4-AP), and the phenols. The products of such an oxidation reaction are the colored quinone-imines (benzodiazepines). Importantly, these products enabled the differentiation of the three common phenols - pyrocatechol, resorcin and hydroquinone, with the use of a novel, spectroscopic method, which was developed for the simultaneous determination of the above three analytes. This spectroscopic method produced linear calibrations for the pyrocatechol (0.4-4.0 mg L(-1)), resorcin (0.2-2.0 mg L(-1)) and hydroquinone (0.8-8.0 mg L(-1)) analytes. In addition, kinetic and spectral data, obtained from the formation of the colored benzodiazepines, were used to establish multi-variate calibrations for the prediction of the three phenol analytes found in various kinds of water; partial least squares (PLS), principal component regression (PCR) and artificial neural network (ANN) models were used and the PLS model performed best.

In many organic reactions, the O(2) activation process involves a key step where inert ground triplet O(2) is excited to produce highly reactive singlet O(2). It remains elusive what factor induces the change in the electron spin state of O(2) molecules, although it has been discovered that the presence of noble metal nanoparticles can promote the generation of singlet O(2). In this work, we first demonstrate that surface facet is a key parameter to modulate the O(2) activation process on metal nanocrystals, by employing single-facet Pd nanocrystals as a model system. The experimental measurements clearly show that singlet O(2) is preferentially formed on {100} facets. The simulations further elucidate that the chemisorption of O(2) to the {100} facets can induce a spin-flip process in the O(2) molecules, which is achieved via electron transfer from Pd surface to O(2). With the capability of tuning O(2) activation, we have been able to further implement the {100}-faceted nanocubes in glucose oxidation. It is anticipated that this study will open a door to designing noble metal nanocatalysts for O(2) activation and organic oxidation. Another perspective of this work would be the controllability in tailoring the cancer treatment materials for high (1)O(2) production efficiency, based on the facet control of metal nanocrystals. In the cases of both organic oxidation and cancer treatment, it has been exclusively proven that the efficiency of producing singlet O(2) holds the key to the performance of Pd nanocrystals in the applications.

Cyclohexanone is an important intermediate in the manufacture of polyamides in chemical industry, but direct selective hydrogenation of phenol to cyclohexanone under mild conditions is a challenge. We report here a catalyst made of Pd nanoparticles supported on a mesoporous graphitic carbon nitride, Pd@mpg-C(3)N(4), which was shown to be highly active and promoted the selective formation of cyclohexanone under atmospheric pressure of hydrogen in aqueous media without additives. Conversion of 99% and a selectivity higher than 99% were achieved within 2 h at 65 °C. The reaction can be accelerated at higher temperature, but even at room temperature, 99% conversion and 96% selectivity could still be obtained. The generality of the Pd@mpg-C(3)N(4) catalyst for this reaction was demonstrated by selective hydrogenation of other hydroxylated aromatic compounds with similar performance.

An effective method was developed for separating gold-nanoparticle clusters in high resolution; dimer and trimer samples were obtained with 95% and 81% purity, respectively.