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Barium oxide is a conventional promoter for various transition‐metal (TM) catalysts in ammonia synthesis. Ba‐promoted Ru catalysts are widely used for ammonia synthesis under mild reaction conditions. However, the promotion mechanism, including the active factor, remains unclear. In this study, the excellent promotion effect of barium oxynitride is reported, which creates anionic electrons in the lattice, forming an electride (BaOxNy:e−z) with the same rocksalt structure as BaO. The BaOxNy:e−z enhances the ammonia synthesis activity of the supported Ru catalyst by 40–100 fold compared with the BaO promotor. This study reveals that a low‐work‐function electron formed in the BaO lattice plays a pivotal role in the electronic promotion effect in catalytic ammonia synthesis, suggesting that BaOxNy:e−z formed near the surface during the ammonia synthesis reaction is an active species for the promotion effect of conventional BaO. [ABSTRACT FROM AUTHOR]

Significant charge recombination that is difficult to suppress limits the practical applications of hematite (α‐Fe2O3) for photoelectrochemical water splitting. In this study, Ti‐modified hematite mesocrystal superstructures assembled from highly oriented tiny nanoparticle (NP) subunits with sizes of ca. 5 nm were developed to achieve the highest photocurrent density (4.3 mA cm−2 at 1.23 V vs. RHE) ever reported for hematite‐based photoanodes under back illumination. Owing to rich interfacial oxygen vacancies yielding an exceedingly high carrier density of 4.1×1021 cm−3 for super bulk conductivity in the electrode and a large proportion of ultra‐narrow depletion layers (<1 nm) inside the mesoporous film for significantly improved hole collection efficiency, a boosting of multihole water oxidation with very low activation energy (Ea=44 meV) was realized. [ABSTRACT FROM AUTHOR]

Serum uric acid (SUA) is a new therapeutic target for non-alcoholic fatty liver disease (NAFLD). In this study, we introduced a chemiluminescence (CL) method combined with microarray technology and a simple fabrication procedure to obtain a highly sensitive SUA probe based on a mesoporous metal oxide nanomaterial. The high-throughput method was based on the generation of H2O2 from SUA by immobilized uricase and its measurement by a CL reaction catalyzed by mesoporous metal oxide nanomaterials. The CL probe was designed for SUA The linear range of the uric acid concentration was 0.6-9 μM and the detection limit was 0.1 μM. In comparison with the other SUA detection techniques, this method has the advantages of a low detection limit, high sensitivity and simplicity. A new sensitive high-throughput approach was obtained for the determination of SUA. [ABSTRACT FROM AUTHOR]

ABSTRACT We developed a sensitive and robust electrogenerated chemiluminescence (ECL) flow sensor based on Ru(bpy)32+ immobilized with a Nepem-211 perfluorinated ion exchange conductance membrane, which has robustness and stability under a wide range of chemical and physical conditions, good electrical conductivity, isotropy and a high exchange capacity for immobilization of Ru(bpy)32+. The flow sensor has been used as a post-column detector in high-performance liquid chromatography for determination of erythromycin and clarithromycin in honey and pork, and tricyclic antidepressant drugs in human urine. Under optimal conditions, the linear ranges were 0.03-26 ng/μL and 0.01-1 ng/μL for macrolides and tricyclic antidepressant drugs, respectively. The detection limits were 0.02, 0.01, 0.01, 0.06 and 0.003 ng/μL for erythromycin, clarithromycin, doxepin, amitriptyline and clomipramine, respectively. There is no post-column reagent addition. In addition to the conservation expensive reagents, the experimental setup was simplified. The flow sensor was used for 2 years with high sensitivity and stability. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Tumor-associated factors are related to increased accumulation of CD11b+Gr1+myeloid-derived suppressor cells (MDSCs). However, the exact mechanism of how genetic factors control the expansion of MDSCs in tumor-bearing hosts remains elusive. Herein, we found that tumor-associated MDSCs and their subsets, mononuclear MDSCs and polymorphonuclear MDSCs, have decreased expression of miR-223 when compared to CD11b+Gr1+ cells from the spleen of disease-free mice. With the differentiation of CD11b+Gr1+MDSCs from bone marrow cells (BMCs) upon exposure to tumor-associated factors, the expression of both pri-miR-223 and mature miR-223 was downregulated, indicating that the expression of miR-223 could be regulated by tumor-associated factors. Interestingly, miR-223 remarkably inhibits differentiation of BMCs into CD11b+Gr1+MDSCs in the presence of tumor-associated factors by targeting myocyte enhancer factor 2C (MEF2C). Using reconstituted s.c. tumor models, miR-223 also suppresses accumulation of CD11b+Gr1+MDSCs, whereas its targeting molecule MEF2C increases the number of MDSCs. Tumor growth is slower in mice infused by miR223-engineered BMCs than in mice infused with control transfected BMCs. As miR-223 and its target molecule MEF2C are highly conserved between mice and humans, the modulation of miR-223 in tumor-induced CD11b+Gr1+MDSCs may exert an important role in controlling the increased accumulation of CD11b+Gr1+MDSCs in patients with tumor. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, the novel trivalent copper-periodate complex {K5[Cu(HIO6)2], DPC} has been applied in a luminol-based chemiluminescence (CL) reaction. Coupled with flow injection (FI) technology, the FI-CL method was proposed for the determination of lincomycin hydrochloride. The CL reaction between luminol and DPC occurred in an alkaline medium. The CL intensity could be greatly enhanced by lincomycin hydrochloride. The relative CL intensity was proportional to the concentration of lincomycin hydrochloride in the range of 1 × 10−8 to 5 × 10−6 g mL−1 and the detection limit was at the 3.5 × 10−9 g mL−1 level. The relative standard deviation at 5 × 10−8 g mL−1 was 1.7% ( n = 9). The sensitive method was successfully applied to the direct determination of lincomycin hydrochloride (ng mL−1) in serum. A possible mechanism of the lumonol-DPC CL reaction was discussed by the study of the CL kinetic characteristics and the spectra of CL reaction. The oxidability of DPC was studied by means of its electrochemical response. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel flow injection chemiluminescence method is proposed for determination of cholesterol in this paper. The cholesterol oxidase was immobilized onto sol-gel and prepared as an enzymatic reaction column. The determination of cholesterol was performed by quantitative determination of hydrogen peroxide produced from an enzymatic reaction. The luminol-H2O2-metal chelate diperiodatocuprate(III) system ensured that the method was highly sensitive and selective. Free cholesterol was determined over the range 5.0 × 10-8 mol/L-5.0 × 10-7 mol/L, with a limit of detection (3σ) of 1.9 × 10-8 mol/L. The relative standard deviation (RSD) for 2.5 × 10-7 mol/L was 2.7% ( n = 7). The proposed method offered the advantages of sensitivity, selectivity, simplicity and rapidity for free cholesterol determination, and was successfully applied to the direct determination of free cholesterol in serum. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A non-competitive immunoassay based on capillary electrophoresis (CE) with chemiluminescence (CL) detection has been developed for the determination of luteinizing hormone (LH) in human serum. The work involved the development of separation and CL conditions, allowing for routine analysis of serum samples. In this study, horseradish peroxidase (HRP)-labelled monoclonal anti-LH can catalyse the luminol-hydrogen peroxide reaction. The determined LH can react with excessive amount of HRP-labelled anti-LH. Within 14 min, free enzyme conjugate and immune complex could be separated in alkaline borate buffer by means of a high voltage (15 kV). To improve sensitivity, a series of measures were adopted, including the choice of para-iodophenol as a CL enhancer, unique design in detect window. Under the optimal conditions, the calibration curve for LH was established in the concentration range 1-200 mIU/mL and the detection limit was 0.08 mIU/mL. Compared with ELISA, this method decreased the detection limit by about 12 times, and it has been successfully employed in the determination of LH in human serum. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel fluorimetric model of on-line electrochemical oxidation for the determination of methotrexate (MTX) is described in this paper. The method was based on the oxidation of MTX to a highly fluorescent product, 2,4-diaminopteridine-6-carboxylic acid, by constant potential in the electrochemical oxidation flow cell. Stopped-flow techniques were employed. Under optimal conditions, the fluorescence intensity of 2,4-diaminopteridine-6-carboxylic acid was measured at excitation and emission wavelengths of 380 and 465 nm, respectively. The calibration graph was linear over concentrations of methotrexate in the range 2.0 × 10−7-1.0 × 10−5 g/mL, with a detection limit of 5.2 × 10−8 g/mL (3 σ). The method has been successfully applied to the determination of methotrexate in human urine samples and showed a percentage recovery in the range 94.3-102.5%. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A highly sensitive flow-injection chemiluminescence (FI-CL) method has been developed for the determination of dihydroxybenzene, based on the hydroxyl radical reaction. Hydroxyl radical (·OH) produced by the reaction of Fe3+ and H2O2 oxidize rhodamine 6G to produce weak CL. It was observed that catechol and hydroquinone greatly enhanced the weak CL reaction. However, the proposed CL system is not suitable for determination of resorcinol because the enhancement reaction is very slow. The proposed procedure has a linear range of 0.01-2 mg/L for catechol, with a detection limit of 0.006 mg/L, and 0.008-1 mg/L for hydroquinone, with a detection limit of 0.004 mg/L. The possible mechanism of the CL system is discussed. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new microflow injection analysis ( µFIA) system on a chip coupled with chemiluminescence (CL) for the non-enzymatic determination of uric acid is described. The µFIA system produced by using two transparent poly(methylmethacrylate) (PMMA) chips measured 50 × 40 × 5 mm, the microchannels, etched by CO2 laser, were 200 µm wide and 100 µm deep, and the volume of the reaction area (RA) was about 1.2 µL. The injection pump, with accurate time control, monitored all reagents, including the sample. The uric acid was sensed by the chemiluminescence reaction between luminol and ferricyanide. The linear range of the uric acid concentration was 0.8-30 mg/L and the detection limit was 0.5 mg/L (S/N = 3). The relative standard deviation was 4.42% for 5 mg/L uric acid ( n = 8). The proposed method has been successfully applied to the non-separation determination of uric acid in human serum and urine. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Chemiluminescence microflow-injection analysis (µFIA) systems on a chip have been developed. The technology of laser ablation was used to fabricate the microchannels on the polymethyl methacrylate (PMMA) chip. The three sampling structure, including double-tee sampling structure, microvalve sampling structure and injection pump with accurate time control, were used. The microcolumn for specific molecular recognition, including molecularly imprinted polymer, enzyme and bacteria, were used to enhance selectivity. These µFIA systems have been applied to clinical analysis, assessment of food safety, in vivo and real-time determination of drugs, and pharmacokinetics studies. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A simple and sensitive flow-injection electrogenerated chemiluminescence (ECL) method for the determination of fluoroquinolones was developed. The method is based on the sensitizing effect of fluoroquinolones on the weak ECL signal of electrochemical oxidation of luminol on the surface of the platinum flake electrode in the medium of 0.1 mol/L Na2CO3-NaHCO3. At the optimum experimental conditions, the relative ECL intensity increased linearly with increasing fluoroquinolones concentration, in the ranges 1.0 × 10−8-2.0 × 10−4 g/mL for norfloxacin, 5.0 × 10−9-6.0 × 10−6 g/mL for oxfloxacin, 2.0 × 10−8-1.4 × 10−5 g/mL for ciprofloxacin, 1.0 × 10−8-1.4 × 10−5 g/mL for pefloxacin, and 1.0 × 10−9-1.0 × 10−5 g/mL for enoxacin, with detection limits of 4.0 × 10−9 g/mL, 2.0 × 10−9 g/mL, 1.0 × 10−8 g/mL, 8.0 × 10−9 g/mL, and 8.0 × 10−10 g/mL, respectively. The relative standard deviations were all less than 2.5% for the determination of 2.0 × 10−6 g/mL fluoroquinolones ( n = 11). The method was used to determine these medicines in pharmaceutical samples with satisfactory results. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A simple, accurate, sensitive and selective fluorescence analysis method for rapid determination of trace amounts of ergometrine maleate has been developed. The method is based on the fluorescence of ergometrine maleate. The calibration graph was linear in the range of 1 × 10−4 to 0.2 µg[sol ]mL and the detection limit was 4 × 10−5 µg[sol ]mL, with a relative standard deviation of 0.32% at 0.05 µg[sol ]mL ( n = 11) ergometrine maleate. The influence of foreign compounds was tested. The proposed method was applied successfully to the determination of ergometrine maleate in pharmaceutical preparations and human plasma. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hematite‐based mesocrystals assembled from highly oriented tiny nanoparticle subunits achieve superior photoelectrochemical water splitting performance under solar irradiation. In their Research Article on page 9047, T. Tachikawa and co‐workers show how rich interfacial oxygen vacancies yield an exceedingly high carrier density and a large proportion of ultra‐narrow depletion layers (<1 nm) inside the mesoporous film, thus boosting multihole water oxidation with a very low activation energy. [ABSTRACT FROM AUTHOR]

Hämatit‐basierte Mesokristalle aus hochorientierten Nanopartikelbausteinen zeigen eine überlegene Aktivität in der photoelektrochemischen Wasserspaltung unter Einstrahlung von Sonnenlicht. Wie T. Tachikawa et al. in ihrem Forschungsartikel auf S. 9132 zeigen, sorgen die reichhaltigen Sauerstoffvakanzen an den Grenzflächen für eine außerordentlich hohe Ladungsträgerdichte sowie eng benachbarte Depletionsschichten (<1 nm) innerhalb des mesoporösen Films. Diese Eigenschaften führen zu einer starken Beschleunigung der Wasseroxidation mit sehr niedriger Aktivierungsenergie. [ABSTRACT FROM AUTHOR]