BACKGROUND Titania dioxide (TiO(2)) photocatalyst is primarily induced by ultraviolet light irradiation. Visible-light responsive anion-doped TiO(2) photocatalysts contain higher quantum efficiency under sunlight and can be used safely in indoor settings without exposing to biohazardous ultraviolet light. The antibacterial efficiency, however, remains to be further improved. METHODOLOGY/PRINC...

TiO₂ photocatalysis is considered as an alternative to conventional disinfection processes for the inactivation of waterborne microorganisms. The efficiency of photocatalysis is limited by charge carrier recombination rates. When the photocatalyst is immobilized on an electrically conducting support, one may assist charge separation by the application of an external electrical bias. The aim of ...

The formation of a dispersed titanium oxide layer on Cabosil-fumed silica and on nonporous silica spheres was studied by infrared and Raman spectroscopies and by transmission electron microscopy (TEM). The procedure for obtaining the titania coatings involved reacting the silanol groups on the silica surface with titanium alkoxides under a N 2 atmosphere. This self-limiting reaction led to a co...

Recently we prepared sulfated, low-molecular-weight lignins (LMWLs) to mimic the biological activities of heparin and heparan sulfate. Chemo-enzymatically prepared sulfated LMWLs represent a library of diverse non-sugar, aromatic molecules with structures radically different from the heparins, and have been found to potently inhibit thrombin and factor Xa. To assess their effect on the fibrinol...

Heparin-like polysaccharides possess the capacity to inhibit cancer cell proliferation, angiogenesis, heparanase-mediated cancer cell invasion, and cancer cell adhesion to vascular endothelia via adhesion receptors, such as selectins. The clinical applicability of the antitumor effect of such polysaccharides, however, is compromised by their anticoagulant activity. We have compared the potentia...

Sulfated polysaccharides from the egg jelly of sea urchins act as species-specific inducers of the sperm acrosome reaction, which is a rare molecular mechanism of carbohydrate-induced signal-transduction event in animal cells. The sea urchin polysaccharides differ in monosaccharide composition (l-fucose or l-galactose), glycosylation, and sulfation sites, but they are always in the alpha-anomer...

Dermatan sulfates and heparin, similar to the mammalian glycosaminoglycans, but with differences in the degree and position of sulfation were previously isolated from the body of the ascidian Styela plicata and Ascidia nigra. These differences produce profound effects on their anticoagulant properties. S. plicata dermatan sulfate composed by 2-O-sulfated alpha-L-iduronic acid and 4-O-sulfated N...

We demonstrate a method for embossing titania sol--gel precursor with poly(methyl methacrylate) (PMMA) molds to make thin films of titania that have dense arrays of 35--65 nm diameter pores, whose features are 1 order of magnitude smaller than those previously demonstrated for sol--gel molding. We show that the high modulus of PMMA is necessary to preserve small features with high aspect ratios...

Coating titania shells onto sub-micron sized particles has been widely studied recently, with success mainly limited to objects with sizes above 50 nm. Direct coating on particles below this size has been difficult to attain especially with good control over properties such as thickness and crystallinity. Here we demonstrate that titanium-glycolate formed by reacting titanium alkoxide and ethyl...