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ZrO2-carbon nanotube (CNT) composites are synthesized through decomposition of Zr(NO3)4.5H2O in supercritical carbon dioxide-ethanol solution with dispersed CNTs at relatively low temperatures and the samples are characterized using various spectroscopies. The chemiluminescent sensor prepared from ZrO2-carbon nanotube composites has displayed dramatic sensitivity as well as high stability and selectivity to ethanol.

A hydrothermal reaction route using dithiol glycol as the sulfur source is used to synthesize wurtzite-type CdS nanostructures, also enabling generation of nanostructures with controllable geometric shapes and structures and thus, optical properties. Their photoluminescence peaks change due of the change in their shape, and these samples facilitate the study of evolution of crystal growth and optical properties, with the shape of the nanocrystals varying from nearly spherical particles to wires.

A simple fabrication of two-dimensional (2D) arrays of zinc sulfide (ZnS) microspheres synthesized with a biomolecule-assisted method is reported. These 2D ZnS colloidal arrays are studied by using ethanol and poly(ethylene glycol) (PEG) and can be used as biosensor and electrooptical devices as well as a platform for studies of energy transfer between colloidal particles.

A simple synthesis using a low-temperature self-assembly synthetic route to generate ZnS microspheres with several hundred nanometer diameters, which are composed of hexagonal wurtzite ZnS nanocrystals, is reported. The results suggest that the monodentage ammonia ligand plays a role comparable to that of the bidentate en ligand in the formation of wurtzite-type ZnS microspheres, exhibiting blue fluorescence emission bands centered at 415 and 466 nm in wavelength.

The chemiluminescence screening method is presented by evaluating the catalytic activity of a gold catalyst. The chemiluminescence (CL) behaviors of catalytic CO oxidation on the surface of various gold catalysts are also examined.

ZrO2−carbon nanotube (CNT) composites have been successfully synthesized via decompositoin of Zr(NO3)4·5H2O in supercritical carbon dioxide−ethanol solution with dispersed CNTs at relatively low temperatures. The samples were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX) analyses. It was demonstrated that CNTs were fully coated with an amorphous ZrO2layer, and the coating layer was nominally complete and uniform. In addition, the thickness of the coating sheath could be readily controlled by tuning the Zr(NO3)4·5H2O/CNTs ratio used. Furthermore, the chemiluminescent sensor prepared from ZrO2−carbon nanotube composites exhibited dramatic sensitivity as well as high stability and selectivity to ethanol. [ABSTRACT FROM AUTHOR]

Fast screening for anabolic steroids in whole urine is achieved by combining reactive desorption electrospray ionization (reactive DESI) and tandem mass spectrometry. Spray solutions containing hydroxylamine allow heterogeneous reactions of hydroxylamine with the carbonyl group of the steroids during the ionization process. Seven steroids, including a glycosteroid, were examined. The ion/molecule reaction adduct and the oxime formed via its dehydration were observed using reactive DESI; the protonated and sodiated forms of the ionized steroid were also observed both in reactive DESI and in DESI performed without the added hydroxylamine reagent. Paper, glass, and polytetrafluoroethylene were tested as sample substrates, but the glycosteroid was ionized intact without hydrolysis only from polytetrafluoroethylene. Limits of detection for the pure compounds were less than 1 ng, dynamic ranges were typically 2 orders of magnitude, and analysis times were just a few seconds. Concentration levels of ketosteroids in raw urine relevant to screening for sports doping (approximately 20 ng/mL) can be reached using a simple solid-phase microextraction (SPME) preconcentration step. Reactive DESI provided significant improvements in ionization efficiency of these steroids in raw undiluted urine as compared to conventional DESI; suppression effects due to the sample matrix were minimal and the urine matrix had no deleterious effect on steroid detection limits. Tandem mass spectrometry provided confirmation of analyte identification in this rapid screening process. [ABSTRACT FROM AUTHOR]

Inductively coupled plasma mass spectrometry (ICPMS) has been successfully used for the detection of element-tagged biomolecules with the advantage of multielement capability. However, this technique cannot be used for microarray detection due to the necessity to dissolve the elemental tags before introducing them to the plasma source. Here, we report the detection of multiple proteins on each spot of the immuno-microarray by laser ablation ICPMS. α-Fetoprotein IgG (AFP), carcinoembryonic antigen (CEA), and human IgG, as model proteins, have been detected on the basis of sandwich-type immunoreactions on a microarray with Sm3+-labeled AFP antibody, Eu3+-labeled CEA antibody, and Au-labeled goat-anti-human IgG (GAB) as labeled antibodies. The detection limits were 0.20, 0.14, and 0.0 12 ng mL-1 (3σ) with the RSD of 5.7%, 2.6%, and 2.3% at the concentration of 1.0 ng mL-1 for AFP, CEA, and human IgG, respectively. The present detection method permits detecting multiple analytes from each spot of microarray with a spatial resolution at micrometer range, which can alleviate the stress to fabricate high-density arrays. Furthermore, the substrate materials and immobilized proteins do not interfere with the detection. The present technique provides a new strategy for readout of microarray. [ABSTRACT FROM AUTHOR]

This paper describes a novel hydride atomizer based on atmospheric pressure dielectric barrier discharge (DBD) plasma. The plasma was generated with a 3700-V, 20.3-kHz, and 5-W electrical power supply and easily sustained with inert gases (He or Ar) at a flow rate of 250 mL.min-1 after optimization. However, it cannot be sustained with N2. This atomizer offers the advantages of low operation temperature and low power consumption in comparison with the currently used electrothermal quartz atomization operated at 900 °C with a power supply of several hundred watts. To confirm the utility of the proposed atomizer, four arsenic species (As(III), As(V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA)) were determined by the present atomization technique. A hyphenation of HPLC coupled to hydride generation MS with the optimized DBD atomizer has been successfully used for the speciation of arsenic in order to demonstrate the potential of this atomizer in the present study. The characteristics of the DBD atomizer and the effects of different parameters (discharge gas, gas flow rate, voltage, HCI concentration, KBH4 concentration) are discussed in the paper. Compared with other hydride atomization techniques, the proposed method shows the following features: (1) small size (70 mm x 15 mm x 5 mm), which is preferable for the miniaturization of the total analytical system; (2) low power consumption (⩽ 5W), which indicates the possibility of the development of portable, fieldable analytical instrumentation for in situ detection using battery as power supply; (3) low atomizer temperature (∼70 °C), which is in favor of the compactness of the total instruments; (4) avoidance of residue moisture removal in comparison with the existed GD system, which leads to the facility of the system. The analytical figures of the present technique were evaluated. The detection limits of As(III), As(V), MMA, and DMA obtained with HG-DBD-AAS were 1.0, 11.8, 2.0, and 18.0 μg.L-1, respectively. The accuracy of the system was verified by the determination of arsenic in reference material of orchard leaves SRM 1571. The concentration of As determined by the present method agreed well with the reference values. The speciation of arsenic in the freeze-dried urine SRM 2670 were carried out, and the results obtained were in agreement with the results of HPLC-ICPMS and the reported values by other laboratories. [ABSTRACT FROM AUTHOR]

A novel aerosol chemiluminescent (CL) detector coupling to capillary electrophoresis (CE) for the detection of saccharides is reported. This CL detector is composed of a postcapillary nebulizer and porous alumina as catalyzer in quartz tube. The CL emission could be generated due to the catalyzing oxidization of saccharides on the surface of porous alumina. The saccharides such as sucrose, α-lactose, maltose, raffinose, galactose, xylose, and glucose with only weak UV absorbance can be successfully detected. The linear ranges of those saccharides are from 30-2000 to 50-2000 mg/L; relative standard deviations range from 2.1 to 3.7% (200 mg/L, n = 11). Compared with the traditional UV detector currently used in CE, this novel detector shows the advantage of high sensitivity to the compounds with only weak UV absorption. Thus, it could be an important supplement of CE detectors for UV- lacking compounds. [ABSTRACT FROM AUTHOR]

Proposes a gas-sensing mode based on chemiluminescence generated on the surface of nanosized titanium dioxide (TiO[sub 2]). Detection of chemiluminescence in the nanosized materials; Characteristics of ethanol and acetone vapors passing through the surface of TiO[sub 2]; Removal of carbon deposited on TiO[sub 2] by controlling the temperature.

Describes the study of atomization of nanoparticles using inductively coupled plasma mass spectrometry (ICPMS). Sensitivity of the gold signal to the organic matrix; Correlation between the method and enzyme-linked immunosorbent assay; Advantages of ICPMS-based nonisotopic immunoassay method for the determination of biologic analytes.

The article presents a study on a catalytic nanomaterial-based optical chemo-sensor array known as electronic tongues that create sensing elements of the array. The researchers made an observation of Chemiluminescence (CL) generated on the surface of solid materials in the mixture of porous silicon with nitric acid. The study found out that CL luminescent efficiencies are different for a given compound on different nanomaterials.