Effect of Ti³⁺ Ions and Conduction Band Electrons on Photocatalytic and Photoelectrochemical Activity of Rutile Titania for Water Oxidation

Although TiO₂ is generally considered to be an oxygen deficient n-type compound, the role of oxygen vacancies and Ti³⁺ ions on its photocatalytic activity is not fully understood. In this study, we investigated the effects of high-temperature calcination and H₂ reduction treatment on the water oxidation activity of rutile TiO₂ under ultraviolet irradiation. Calcination above 900 °C decreased the photocatalytic activity of the TiO₂ owing to strong oxidation, but its initial activity was restored by H₂ treatment at above 500 °C. Electron spin resonance (ESR) spectra showed that the high-temperature calcination created O^•– radicals (trapped hole in oxygen lattice site), while the H₂ reduction treatment created Ti³⁺ ions (trapped electron in titanium lattice site) with oxygen vacancies. Diffuse reflectance ultraviolet–visible–near-infrared (UV–vis–NIR) spectroscopy indicated an increase in the amount of electrons in shallow traps and the conduction band with H₂ treatment temperature. Measurements of the sheet resistance and space charge layer capacitance of the thermally oxidized TiO₂ films indicated that the H₂ treatment improved the electrical conductivity owing to an increase in donor density (electron density). Thus, the increase in the photocatalytic and photoelectrochemical activities of the rutile TiO₂ was attributed to donor doping by H₂ reduction

Noble-Metal-Free NO_<i>x</i> Storage over Ba-Modified TiO₂ Photocatalysts under UV-Light Irradiation at Low Temperatures

Photoassisted nitrogen oxide (NO_<i>x</i>) storage was investigated over the barium-modified titanium dioxide (Ba/TiO₂) photocatalysts under UV-light irradiation at a high concentration of nitrogen monoxide (NO) of 200 ppm and a high gas hourly space velocity (GHSV) of 50 000 h^–1. The NO removal efficiency was kept >99% during the 1020 s interval from the start of the reaction over the Ba/TiO₂ photocatalyst. The temperature-programed desorption (TPD) measurement and X-ray diffraction (XRD) technique revealed that barium oxide (BaO) species functioned as a NO_<i>x</i> storage material even at low temperatures, which result in improvement of the performance of the photoassisted NO_<i>x</i> storage

Time-courses of the plasma concentration, and bone, liver, kidney, and lung accumulation of ¹¹¹In-labeled BSA derivatives in mice after intravenous injection at a dose of 1 mg protein/kg.

<p>The total wet bone weight was estimated as 12% of the body weight, and the radioactivity in the bone was based on activity determined in tibiae and femurs extrapolated to whole wet bone as reported previously [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135966#pone.0135966.ref022" target="_blank">22</a>].Results are expressed as the mean ± S.D. of three mice. ●: BSA, ○: BSA-ALN (3), ▼: BSA-ALN (28), ▽: BSA-ALN (40).</p

Time-courses of the plasma concentration, and bone, liver, kidney, and lung accumulation of ¹¹¹In-labeled GR derivatives in mice after intravenous injection at a dose of 1 mg protein/kg.

<p>The total wet bone weight was estimated as 12% of the body weight, and the radioactivity in the bone was based on activity determined in tibiae and femurs extrapolated to whole wet bone as reported previously [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135966#pone.0135966.ref022" target="_blank">22</a>]. Results are expressed as the mean ± S.D. of three mice. ●: GR, ○: GR-ALN (4), ▼: GR-ALN (17).</p

Physicochemical characteristics of ALN-modified proteins.

<p>^a) The alendronate (ALN) content was determined by the molybdenum method using ALN as a standard. The number of ALN residues was calculated using the molar ratio of ALN residues attached to the protein.</p><p>^b)The number of PEG was estimated by the number of unreacted free amino groups, which was determined by the trinitrobenzenesulfonic acid method.</p><p>^c) The molecular weight of each protein derivative was estimated by considering of the number of ALN residues and PEG modifications.</p><p>N.D.; not determined</p><p>Physicochemical characteristics of ALN-modified proteins.</p

Physicochemical characteristics of ALN-modified proteins.

<p>^a) The alendronate (ALN) content was determined by the molybdenum method using ALN as a standard. The number of ALN residues was calculated using the molar ratio of ALN residues attached to the protein.</p><p>^b)The number of PEG was estimated by the number of unreacted free amino groups, which was determined by the trinitrobenzenesulfonic acid method.</p><p>^c) The molecular weight of each protein derivative was estimated by considering of the number of ALN residues and PEG modifications.</p><p>N.D.; not determined</p><p>Physicochemical characteristics of ALN-modified proteins.</p

Craniocaudal maximum intensity projections of reconstructed magnetic resonance angiography.

<p>(A) SoS image and sample images from a visual rating of (B) 1 (α = 1.0 × 10⁻⁴, β = 3.2 × 10⁻³), (C) 2 (α = 1.0 × 10⁻⁷, β = 1.0 × 10⁻⁶), (D) 3 (α = 3.2 × 10⁻⁵, β = 1.0 × 10⁻⁴), (E) 4 (α = 1.0 × 10⁻⁶, β = 1.0 × 10⁻⁵) and (F) 5 (α = 3.2 × 10⁻⁵, β = 3.2 × 10⁻⁵).</p

AUC and clearance of ¹¹¹In-labeled ALN-modified proteins in mice after intravenous injection of 1 mg protein/kg.

<p>AUC and clearance of ¹¹¹In-labeled ALN-modified proteins in mice after intravenous injection of 1 mg protein/kg.</p

Permeation of sumatriptan succinate across human skin using multiple types of self-dissolving microneedle arrays fabricated from sodium hyaluronate

<p>Available formulations of sumatriptan succinate (SS) have low bioavailability or are associated with site reactions. We developed various types of self-dissolving microneedle arrays (MNs) fabricated from sodium hyaluronate as a new delivery system for SS and evaluated their skin permeation and irritation in terms of clinical application. <i>In vitro</i> permeation studies with human skin, physicochemical properties (needle length, thickness and density), and penetration enhancers (glycerin, sodium dodecyl sulfate and lauric acid diethanolamide) were investigated. SS-loaded high-density MNs of 800 µm in length were the optimal formulation and met clinical therapeutic requirements. Penetration enhancers did not significantly affect permeation of SS from MNs. Optical coherence tomography images demonstrated that SS-loaded high-density MNs (800 µm) uniformly created drug permeation pathways for the delivery of SS into the skin. SS-loaded high-density MNs induced moderate primary skin irritations in rats, but the skin recovered within 72 h of removal of the MNs. These findings suggest that high-density MNs of 800 µm in length are an effective and promising formulation for transdermal delivery of SS. To our knowledge, this is the first report of SS permeation across human skin using self-dissolving MNs.</p

Effect of the number of ALN residues on bone accumulation of ¹¹¹In-labeled ALN-modified proteins.

<p>¹¹¹In-labeled ALN-modified proteins were intravenously administered into mice at a dose of 1 mg protein/kg. The total wet bone weight was estimated as 12% of the body weight, and the radioactivity in the bone was based on activity determined in tibiae and femurs extrapolated to whole wet bone as reported previously [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135966#pone.0135966.ref022" target="_blank">22</a>]. Results are expressed as the mean ± S.D. of three mice. ●: GR-ALN, ▲: BSA-ALN, □: SOD-ALN, ○: LZM-ALN, △: PEG-SOD-ALN.</p