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Albumin, the most abundant protein in plasma, has been widely used in drug delivery studies. Here, we developed maleimide-functionalized liposomes (Mal-Lip) that can bind to endogenous albumin to improve the tumor targeting efficiency of liposomes. Transmission electron microscopy and gel electrophoresis studies showed that albumin can bind to Mal-Lip due to the chemical coupling of the albumin thiol groups with the maleimide group. Both conventional liposomes and Mal-Lip showed minimal cytotoxicity within the tested range of lipid concentrations, indicating that the maleimide functionality did not increase the toxicity of liposomes to various cells. Mal-Lip was taken up by 4T1 cells to a greater extent than conventional liposomes, and Mal-Lip accumulated in 4T1 tumors in mice more than conventional liposomes after intravenous injection. These results suggest that the maleimide group can improve the tumor targeting efficiency of liposomes in vivo by binding to endogenous albumin in situ. However, the maleimide group also enhanced the uptake of Mal-Lip by Raw264.7 cells and shortened their time in circulation, indicating that further studies should be performed to prevent elimination of Mal-Lip by the immune system.

Norfloxacin (NF) is an emerging antibiotic contaminant due to its significant accumulation in the environment. Photocatalytic degradation is an effective method for removing emerging contaminant compounds in aqueous solution; however, it is not commonly applied because of the poor solubility of contaminant compounds in water. In this study, a photocatalytic degradation experiment was carried out on NF using a self-made ceria catalyst. At an initial concentration of NF of 2.5 mg L -1 , the dosage of CeO₂ was 0.1 g L -1 photocatalyst in water, and the initial pH of the NF solution was 8.0. With a reaction time of 180 min, the total removal rate of NF could reach 95%. Additionally, the studies on hydrogen production show that the maximum hydrogen production with 2% Fe-CeO₂ can reach 25,670 μ mol h -1 g -1 under close to 8 W of 365 nm, a methanol concentration of 20%, and a catalyst dose of 0.1 g L -1 photocatalyst in water. Furthermore, the intensities of photoluminescence (PL) emission peaks decreased with increased Fe-doped amounts on CeO₂, suggesting that the irradiative recombination seemed to be weakened.

Hierarchical rose-like structured MnCo₂O₄ spinel was synthesized via a facile solvothermal process using polyvinyl pyrrolidone (PVP) as the soft template, which was characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), etc. When evaluated as the anode materials for lithium ion batteries, the as-synthesized MnCo₂O₄ spinel exhibited excellent cycling performance and rate capacity. The initial discharge and charge capacity reached 1502 mA·h·g -1 and 1131 mA·h·g -1 at the current density of 100 mA·g -1 , respectively.

The exact mechanism of delayed death of Toxoplasma gondii is not known. FAS II synthesis in the apicoplast of T. gondii is essential for the survival of Toxoplasma gondii, while β-hydroxyacylacyl carrier protein dehydratase (FabZ) is indispensable for fatty acid synthesis. The present study investigated the relationship between the delayed death of T. gondii by inducing metabolic disorders due to suppression the expression of FabZ. A tetracycline-induced knockout vector inserted with T. gondii fabZ gene was constructed, and transfected into T. gondii TATi strain by electroporation. The stable mutants with tetracycline-induced knockout were selected, expression of FabZ was suppressed by using anhydrotetracycline (ATc), and FAS II deficient tachyzoites were prepared. The Western blot and qPCR results revealed that proliferation of FAS II deficient tachyzoites was not significantly different compared to the normal tachyzoites at 24 h and 48 h; however, after 72 h, the number of T. gondii tachyzoites in the ATc treated group was significantly (p < 0.05) less than that of non-treated group, indicating the delayed death of T. gondii caused by the loss of apicoplast and decrease in the expression of FabZ, which inhibited the FAS II metabolism. The results of this study can be used for prevention of toxoplasmosis by inducing delayed death of T. gondii.

Nanomaterials have been widely used to immobilize biomolecules, amplify the signals and concentrate the analytes for detection with good properties including large surface area, good adsorption capacity and high surface activity. In recent years, nanomaterials such as carbon nanomaterials, noble metal nanomaterials, polymers, are widely applied to research and develop immunosensors with high sensitivity and selectivity, which monitor the antigen-antibody reaction for the detection of tumor markers. This review provides an introduction of immunosensors and focuses on the design of electrochemical (EC) immunosensors, electrochemical luminscence (ECL) immunosensors and photoelectrochemical (PEC) immunosensors based on nanomaterials in nearly three years.

In this paper, M3(VO4)2 (M = Mg, Ca, Sr, and Ba) self-activated phosphors were prepared by a solid-state reaction method at 1,000 °C for 5 h. The phase formation and micrographs were analyzed by X-ray diffraction and scanning electron microscopy. The Ca3(VO4)2 phosphor does not show any emission peaks under excitation with ultraviolet (UV) light. However, the M3(VO4)2 (M = Mg, Sr, and Ba) samples are effectively excited by UV light chips ranging from 200 nm to 400 nm and exhibit broad emission bands due to the charge transfer from the oxygen 2p orbital to the vacant 3d orbital of the vanadium in the VO4. The color of these phosphors changes from yellow to light blue via blue-green with increasing ionic radius from Mg to Sr to Ba. The luminescence lifetimes and quantum yield decrease with the increasing unit cell volume and V-V distance, in the order of Mg3(VO4)2 to Sr3(VO4)2 to Ba3(VO4)2. The emission intensity decreases with the increase of temperatures, but presents no color shift. This confirms that these self-activated M3(VO4)2 phosphors can be suggested as candidates of the single-phase phosphors for light using UV light emitting diodes (LEDs).

Using Ce(NO₃)₃· 6H₂O, Fe(NO₃)₃· 9H₂O and Ni(NO₃)₃· 6H₂O as the main raw materials, nano Ni-doped CeFeO₃ was prepared by the microwave method for the first time. The Ni-doped CeFeO₃samples were characterized by XRD, SEM, DRS and EDS. The results show that Ni-doped CeFeO₃exhibits a perovskite structure (ABO₃), and contains nanosheets less than 10 nm thick. The prepared nanosheets have an optical band gap of 1.93 eV. The effect of different doping amounts on the photocatalytic properties of Ni-doped CeFeO₃ was studied under visible light, using methyl-orange. When the concentration of the methyl-orange solution was 10 mg/L, and the illumination time allowed for photocatalysis was 90 min, the degradation rate rose to nearly 98%. Moreover, Ni-doped CeFeO₃ has a higher photocatalytic activity than pure CeFeO₃ powder, making it suitable for a broad range of applications.

Well-crystallized NaTaO3 nanoparticles doped with and without Bi were synthesized by a hydrothermal method. X-ray diffraction (XRD) patterns showed a systematic shift toward lower angles, which was followed by broadened peaks as the dopant content of Bi3+ increased. The doping of Bi3+ in NaTaO3 was also found to give rise to finer particle sizes. For undoped samples, transmission electron microscopy (TEM) showed the well-crystallized cubic morphology, which however, changed to fairly rough surfaces and somewhat irregular distorted cube-like shaped geometries with the addition of Bi3+. The swelling of the crystallized cell volume was demonstrated by the increased lattice d-spacing from high-resolution transmission electron microscopy (HRTEM) studies. The diffuse reflection spectra showed a red shift in absorbance wavelength with Bi3+ doping, which suggests a decreased band gap energy. Emissions of the TaO6 octahedra unit were observed at 435 nm in the photoluminescence (PL) spectra. The PL intensities increased with the doping content of Bi3+, which was attributed to the increase of oxygen vacancies caused by the substitution of Ta5+ by Bi3+. The photocatalytic degradation of methylenebluechloride was taken as the model reaction to examine the activity of the sample. It was found that the activity decreased with the Bi3+ content.

Serial semiconductors core-shell and hollow sphere structures were prepared by using silica colloidal spheres as template in alkaline solution. This method presented in this paper involves mainly two steps with metal ions stored into surface layer of silica colloidal spheres in alkaline condition in the first step, followed metal ions reacted with thioacetamide to form semiconductor shell under microwave heating in a short-time. Cadmium ions were used as an example to illustrate the synthesis process. The electron microscopy results suggested that CdS core-shell structure and hollow spheres with complete and uniform shell were successfully synthesized, and the thickness of shell can be controlled in a certain range precisely. The mechanism of this method was discussed in detail. In addition, complex peanut hollow structure was synthesized by using this method, which indicated that this method might be extended to synthesize desired morphology with corresponding silica template. This novel method provides an avenue to synthesize uniform different semiconductor core-shell structure and hollow spheres with controllable morphology and shell thickness.

We have used Raman spectroscopy to study the behavior of multi-walled boron nitride nanotubes and hexagonal boron nitride crystals under high pressure. While boron nitride nanotubes show an irreversible transformation at about 12 GPa, hexagonal boron nitride exhibits a reversible phase transition at 13 GPa. We also present molecular dynamics simulations which suggest that the irreversibility of the pressure-induced transformation in boron nitride nanotubes is due to the polar nature of the bonds between boron and nitrogen.

Adopting a wet chemistry method, Au and Fe3O4 nanoparticles were functionalized on boron nitride nanotubes (BNNTs) successfully for the first time. X-ray diffraction pattern and transmission electron microscopy were used to characterize the resultant products. Subsequently, a method was proposed to fabricate heterojunction structures based on the particle-functionalized BNNTs. As a demonstration, BNNT-carbon nanostructure, BNNT-ZnO and BNNT-Ga2O3 junctions were successfully fabricated using the functionalized particles as catalysts.

A methanol-thermal method has been developed to fabricate one-dimensional composite nanowires by coating multiwalled carbon nanotubes with lanthanum oxide and iron oxide, respectively. The coating structure and composition have been investigated by transmission electron microscopy and the X-ray energy dispersive spectrum. Magnetic measurement for the iron oxide coatings indicated that the coercivity has been enhanced after coating. The method reported here provides a novel procedure for the fabrication of one-dimensional composite nanostructures.

SiC nanowires are effective reinforcement materials in ceramic matrix composites. A compliant coating such as carbon on nanowires is necessary in order to moderate the nanowire/matrix interfacial bounding for taking the most advantages of SiC nanowires. SiC nanowires with an in-situ deposition of carbon shell coating were fabricated by a novel chemical vapor growth process. Highresolution transmission electron microscopy examinations showed that the nanowires consisted of a single crystal beta-SiC core with an amorphous carbon shell 2-5 nm in thickness. The nanowires were straight with a length generally over 10 microm and a diameter 15-150 nm. The growth direction of the core SiC nanowires is (111). A simple three-step growth model for SiC nanowires was proposed based on a vapor-solid growth mechanism. Because the carbon-coated nanowires were grown directly on continuous Tyranno-SA SiC fibers, in-situ application of the present technique on the fabrication of SiC nanowire-reinforced SiC/SiC composites is expected.

Comparative study on the diameter distribution of MgO nanowires has been carried out. MgO nanowires could be synthesized by the direct reaction between metallic magnesium and silica, and the obtained nanowires have diameters ranging from 50 to 200 nm and lengths of several hundreds nanometers, exhibiting a straight wire. The diameter can be downscaled to smaller than 50 nm, and the nanowire exhibits a curved and twisted one-dimensional structure with lengths up to several micrometers, when a fine support catalyst was used as the reactant. The diameter-controlled growth mechanism was also explained in this work.