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The direct conversion of syngas into lower olefins is a highly attractive route for the synthesis of lower olefins. The selectivity of lower olefins via the conventional Fischer–Tropsch (FT) synthesis is restricted to ∼60% with high CH4 selectivity due to the limitation by the Anderson–Schulz–Flory (ASF) distribution. Here, we report the design of bifunctional catalysts for the direct conversion of syngas into lower olefins with selectivity significantly breaking the ASF distribution. The selectivity of C2–C4 olefins reached 87% at a CO conversion of 10% and was sustained at 77% by increasing CO conversion to 29% over a bifunctional catalyst composed of Zn-doped ZrO2 nanoparticles and zeolite SSZ-13 nanocrystals. The selectivity of CH4 was lower than 3% at the same time. It is demonstrated that the molar ratio of Zn/Zr, the density of Bronsted acid sites of SSZ-13 and the proximity of the two components play crucial roles in determining CO conversion and lower-olefin selectivity. Our kinetic studies indicate that methanol and dimethyl ether (DME) are key reaction intermediates, and the conversion of syngas to methanol/DME is the rate-determining step over the bifunctional catalyst. Formate and methoxide species have been observed on Zn-doped ZrO2 surfaces during the activation of CO in H2, and the formed methanol/DME are transformed into lower olefins in SSZ-13.

Detection and isolation of circulating tumor cells (CTCs) play a pivotal role in the diagnosis and prognosis of cancer, while the high capture efficiency and purity of CTCs are difficult to achieve simultaneously among the various isolation methods. In this work, we designed an inverted microchip integrating silicon nanowires (SiNWs) and multifunctional magnetic nanocomposites (Fe3O4@C6/Ce6@silane, Coumarin 6 (C6), Chlorin e6 (Ce6)) for enhanced capture efficiency and purity of CTCs. The Fe3O4@C6/Ce6@silane conjugated with antibody can label the CTCs and pull them to the upside SiNWs capture surface by the upward magnetic field with high purity. This inverted structure was also featured with real-time detection and photodynamic therapy (PDT) of CTCs with the confocal laser scanning microscope (CLSM). The results indicate the important role of the composites labels and the magnetic field, which greatly improves the capture purity of the CTCs to 90%. Meanwhile, capture efficiency of CTCs achieve to 90.3% in culture medium and 82% in blood with 2 mL/h flow rate, respectively. Based on the structure of the device and composites, the captured CTCs could be directly inactivated by the in situ photodynamic therapy in the capture process which holds positive impact to block cancer spread.

Cobalt nanoparticles were loaded onto mesoporous zeolite Na–Y (Na–meso-Y) by melt infiltration and impregnation methods. As compared to impregnation, melt infiltration resulted in Co nanoparticles with a narrower size distribution. The Co/Na–meso-Y catalyst prepared by the melt infiltration exhibited higher C10–C20 (diesel fuel) selectivity. The hydrogenolysis of heavier hydrocarbons was confirmed to occur under Fischer–Tropsch reaction conditions. Our studies for the hydrogenolysis of n-hexadecane revealed that the catalyst by the melt infiltration was more active and selective for the formation of C10–C15 hydrocarbons. We propose that the narrower Co size distribution favors the selective hydrogenolysis and thus the C10–C20 selectivity in Fischer–Tropsch synthesis. The addition of Mn with a proper content could further improve the diesel fuel selectivity to 65% by suppressing the formations of CH4 and lighter hydrocarbons. The Mn-modified Co/Na–meso-Y catalyst was very stable and no deactivation was obs...

A novel solvent-thermal Y2O3 template method was explored to synthesise NaYF4:Yb3+,Tm3+ IOPCs, which show highly improved UCL properties.

Background: Polyacrylic acid (PAA)–coated gold nanorods (GNRs) were prepared in this research, and then the structure, stability, temperature increment efficiency, and biocompatibility of GNRs@PAA were detected. Methods: It was demonstrated that GNRs@PAA coupled with an 808 nm laser had superior efficiency of hyperthermia therapy for MG63 human osteosarcoma cell. Results: The mechanism of photothermal therapy of GNRs@PAA was explored, and it was proved that damaged cell membrane and DNA integration caused cell apoptosis and death, and the cell apoptosis rate had been obviously promoted by in vitro photothermal therapy which exhibited time–dose dependence. Conclusion: The results demonstrated that the GNRs@PAA could be a promising candidate for phototherapeutic applications in human osteosarcoma.

Artificial fractal structures have attracted considerable scientific interest in circulating tumor cells (CTCs) detection and capture, which plays a pivotal role in the diagnosis and prognosis of cancer. Herein, we designed a bionic TiO2 inverse opal photonic crystal (IOPC) structure for highly efficient immunocapture of CTCs by combination of a magnetic Fe3O4@C6@silane nanoparticles with anti-EpCAM (antiepithelial cell adhesion molecule) and microchannel structure. Porous structure and dimension of IOPC TiO2 can be precisely controlled for mimicking cellular components, and anti-EpCAM antibody was further modified on IOPC interface by conjugating with polydopamine (PDA). The improvement of CTCs capture efficiency reaches a surprising factor of 20 for the IOPC interface compared to that on flat glass, suggesting that the IOPCs are responsible for the dramatic enhancement of the capture efficiency of MCF-7 cells. IOPC substrate with pore size of 415 nm leads to the optimal CTCs capture efficiency of 92% wi...

Regenerative medicine aims to achieve functional rehabilitation of tissue or cells injured through wound, disease, or aging. Recent findings suggest that nanotechnology provides advanced biomaterials with specified morphologies which can create a nanoscale extracellular environment capable of promoting the adhesion and proliferation of stem cells and accelerating stem cell differentiation in a controlled manner in tissue engineering. This review summarizes the biological effects of nanomaterials and their regenerative medicine applications in orthopedic surgery research, including bone, cartilage, tendons, and nerve tissue engineering.

In this work, a new photoelectrochemical biosensor based on Ag2S nanoparticles (NPs) modified macroporous ZnO inverse opals structure (IOs) was developed for sensitive and rapid detection of alpha fetal protein (AFP). Small size and uniformly dispersed Ag2S NPs were prepared using the Successive Ionic Layer Adsorption And Reaction (SILAR) method, which were adsorbed on ZnO IOs surface and frame work as matrix for immobilization of AFP. The composite structure of ZnO/Ag2S expanded the scope of light absorption to long wavelength, which can make full use of the light energy. Meanwhile, an effective matching of energy levels between the conduction bands of Ag2S and ZnO are beneficial to the photo-generated electrons transfer. The biosensors based on FTO (fluorine-doped tinoxide) ZnO/Ag2S electrode showed enough sensitivity and a wide linear range from 0.05 ng/mL to 200 ng/mL with a low detection limit of 8 pg/mL for the detection of AFP. It also exhibited high reproducibility, specificity and stability. The proposed method was potentially attractive for achieving excellent photoelectrochemical biosensor for detection of other proteins.