The importance of permeability as well as solubility of the drug has been recognized in improving the solubility of poorly water-soluble drugs. This study investigated the impact of amorphous composites of indomethacin (IMC) and sulindac (SLD) on the membrane permeability of drugs. The IMC/SLD (1/1) formulation prepared by dry grinding was amorphous with a single glass transition temperature. The Fourier transform IR spectra and Raman spectra revealed formation of hydrogen bonds between the OH group of IMC and the carbonyl group of SLD. These results suggest that an amorphous composite was formed between IMC and SLD through hydrogen bonding. The amount of dissolved IMC and SLD from the amorphous composite of IMC/SLD (1/1) was higher than that of the untreated IMC or SLD in the dissolution test. The permeated amounts and permeation rates of both drugs were enhanced by increasing the solubility of the amorphous composite. Conversely, the apparent membrane permeability coefficients (P app ) were almost same for untreated drugs and amorphous composites. In the case of hydroxypropyl-β-cyclodextrin and sodium dodecyl sulfate, P app of the drugs decreased with the addition of these compounds, although the drug solubility was enhanced by the solubilization effect. This study revealed that an amorphous composite formed through hydrogen bonding is an attractive pharmaceutical way to enhance the permeated amount and permeation rate without changing the P app of both the drugs.

13 14 H 2 S decomposition was examined in the gas and liquid phases over TiO 2 photocatalyst. In the gas phase reaction, H 2 was obtained 15 using TiO 2 as a photocatalyst. After the photocatalytic reaction, the color of TiO 2 changed from white to yellow. SEM-EDS results 16 revealed that sulfur was present on the TiO 2 surface. H 2 evolution rate was remarkably higher in the liquid phase reaction than in 17 the gas phase reaction. Thus, liquid phase reaction is optimal to obtain H 2 from the decomposition of H 2 S. Ethanolamine as a solvent 18 of H 2 S underwent little photocatalytic decomposition. TiO 2 photocatalyst has high potential for use in a new H 2 recycling process 19 in the petroleum industry. 20

Coamorphous formulation is a useful approach for enhancing the solubility of poorly water-soluble drugs via intermolecular interactions. In this study, a hydrogen-bondingbased coamorphous system was developed to improve drug solubility, but it barely changed the apparent permeability (P app ) of the drug. This study aimed to design a novel coamorphous salt using ionic interactions to improve drug permeability and absorption. Telmisartan (TMS), with an acidic group, was used to form a coamorphous salt with basic amlodipine (AML). Evaluation of the physicochemical properties confirmed the formation of a coamorphous salt via ionic interactions between the amine group of AML and the carboxyl group of TMS at a molar ratio of 1:1. The coamorphous salt of TMS/AML enhanced the partitioning of both drugs into octanol, indicating increased lipophilicity owing to the interaction between TMS and AML. The coamorphous salt dramatically enhanced TMS solubility (99.8 times that of untreated TMS) and decreased AML solubility owing to the interaction between TMS and AML. Although the coamorphous salt showed a decreased P app in the permeation study in the presence of a thicker unstirred water layer (UWL) without stirring, P app increased in the presence of a thinner UWL with stirring. The oral absorption of TMS from the coamorphous salt increased by up to 4.1 times compared to that of untreated TMS, whereas that of AML remained unchanged. Although the coamorphous salt with increased lipophilicity has a disadvantage in terms of diffusion through the UWL, the UWL is thin in human/animal bodies owing to the peristaltic action of the digestive tract. Dissociation of the coamorphous salt on the membrane surface could contribute to the partitioning of the neutral form of drugs to the membrane cells compared with untreated drugs. As a result, coamorphous salt formation has the advantage of improving the membrane permeation and oral absorption of TMS, owing to the enhanced solubility and supply of membrane-permeable free TMS on the surface of the membrane.

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Mit Pt beladene CdS‐Pulver mit hexagonaler Struktur zeigen eine wesentlich höhere Effizienz als Photokatalysator bei der H2‐Entwicklung aus wäßrigen Sulfitlösungen als solche mit kubischer Kristallstruktur.