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To achieve selective recognition of water-soluble ionic compounds, we developed an effective preparation method that can construct specific recognition sites on a cross-linked polymer surface using ionic complexes of functional monomers and template molecules. The specific ionic complexes used for selective recognition were attached on the surface of cross-linked polymer pores via a reaction between ionic complexes and unreacted vinyl groups on the polymer. In this paper, we show that ionic complexes can attach to the polymer surface by determining the number of unreacted vinyl groups on the cross-linked base polymer. The prepared polymers had greater effective adsorption ability than normally prepared molecularly imprinted polymer because there were no dead sites in the cross-linked network. Furthermore, according to chromatographic evaluations involving frontal analyses, the prepared polymer has selective recognition ability based on the interval recognition of ionic compounds. The adsorption isotherm also suggests selectivity for the template molecule on the prepared polymer. Finally, the paralytic shellfish poison saxitoxin was selectively extracted using the prepared polymer. [ABSTRACT FROM AUTHOR]

In this study, we described the fundamental properties of novel polymer monoliths that were prepared from a water‐soluble crosslinking agent. Each monolith was evaluated by scanning electron microscope (SEM) and scanning probe microscope (SPM) to observe the monolithic structure, and the polymer films that were prepared from several monomers were evaluated by the contact angle of water. As results of evaluations, the polymer prepared from a water‐soluble crosslinking agent had high hydrophilicity. Furthermore, SEM evaluations suggested that polymer porogenic solvent (PEG) was contributed to the construction of monolithic structure, and the polymerization degree of PEG was also taken effect of the structural changing by the variation of phase separation. Additionally, the results of SPM evaluations and the differences of monolithic structure were also reflected under water condition although the swelling of polymer was observed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3811–3817, 2007 [ABSTRACT FROM AUTHOR]

Imidazolium salt type ionic liquids containing cyclic siloxane frameworks were successfully prepared by the hydrolytic condensation of 1-[3-(dimethoxymethylsilyl)propyl]-3-methylimidazolium chloride, which was synthesized by the reaction of 3-chloropropyldimethoxymethylsilane and 1-methylimidazole, using the superacid catalysts bis(trifluoromethane-sulfonyl)imide and trifluoromethanesulfonic acid. [ABSTRACT FROM AUTHOR]

We examined chromatographic retention properties of macroporous spongy monolithic columns. Detailed chromatographic evaluations showed that planar compounds were strongly retained on poly(ethylene-co-vinyl acetate)-based monoliths, whereas sterically bulky or hydrophilic compounds were weakly retained. The comparison results with commonly used columns suggested that the specific retention abilities were a result of the differences in the polymer-chain orientation on polymer pore surface. [ABSTRACT FROM AUTHOR]

Heyde syndrome describes the triad of aortic stenosis, acquired coagulopathy, and anemia due to bleeding from intestinal angiodysplasia. An 87-year-old man with iron deficiency anemia due to melena was admitted to our hospital. On examination, a systolic murmur was heard and echocardiography confirmed the presence of aortic stenosis. Esophagogastroduodenoscopy and colonoscopy were unremarkable. Capsule endoscopy and double balloon endoscopy revealed angiodysplasia throughout the small intestine. Laboratory investigations were significant for reduced plasma levels of high molecular weight von Willebrand factor multimers. On the basis of these findings, the patient was diagnosed with Heyde syndrome. The patient required frequent blood transfusions because of the intestinal bleeding, and underwent bioprosthetic aortic valve replacement. Twenty months after the operation, the gastrointestinal bleeding resolved and the patient no longer required blood transfusions. This is the first case report to describe an improvement in bleeding from angiodysplasia, one year after aortic valve replacement. It demonstrates the effective treatment of Heyde syndrome with aortic valve replacement, and highlights the importance of considering this differential diagnosis when evaluating patients presenting with repeated episodes of gastrointestinal bleeding and a concurrent systolic murmur. [ABSTRACT FROM AUTHOR]

Ultrahigh-efficiency separations based on the presence of one deuterium in benzene, toluene, and naphthalene were achieved by recycle chromatography using C18 silica columns. Larger isotopic separation factors, α(H/D), were observed in methanol-water than in acetonitrile-water, when the mobile phases provided similar retention factors (k), or similar methylene selectivity, α(CH2). Isotopic resolutions between nondeuterated and perdeuterated aromatic hydrocarbons at long separation times were estimated by using the plate counts obtainable by recycle operation as a function of a cycle time, along with the retention factors and the separation factors experimentally observed. Methanol-acetonitrile-water ternary mobile phases were predicted to provide the greatest resolution per unit time, and actually enabled separation by the difference of one H/D substitution on the aromatic hydrocarbons with α(H/D) = 1.008 or less, and also the differentiation of the isomers of monodeuterated toluene with α(toluene-4-d/toluene-α-d) = 1.0016. The discrimination mechanism of H/D isotopic species is discussed based on the dispersion interactions of a CH/CD group of the solute with the stationary phase as well as the mobile phase. [ABSTRACT FROM AUTHOR]