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Diatoms are unicellular algae of enormous biodiversity that occur in all water habitats on earth. Their cell walls are composed of amorphous biosilica and exhibit species-specific nanoporous to microporous and macroporous patterning. Therefore, diatom biosilica is a promising renewable material for various applications, such as in catalysis, drug-delivery systems, and biophotonics. In this study, diatom biosilica of three different species ( Stephanopyxis turris , Eucampia zodiacus , and Thalassiosira pseudonana ) was used as support material for gold nanoparticles using a covalent coupling method. The resulting catalysts were applied for the oxidation of d -glucose to d -gluconic acid. Because of its high specific surface area, well-established transport pores, and the presence of small, homogeneously distributed gold nanoparticles on the surface, diatom biosilica provides a highly catalytically active surface and advanced accessibility to the active sites. In comparison to those of the used reference supports, higher catalytic activities (up to 3.28 × 10 –4 mmol Glc s –1 mg Au –1 for T. pseudonana biosilica) and slower deactivation were observed for two of the diatom biosilica materials. In addition, diatom biosilica showed very high gold-loading capacities (up to 45 wt %), with a homogeneous nanoparticle distribution.

A novel strategy for a directed nanoparticle coupling to isolated Stephanopyxis turris valves is presented. After pyrolysis, the valves exhibit incomplete wetting due to their characteristic T-shaped profiles as a prerequisite for a regioselective coupling reaction. A micromanipulation system allows for precise handling and their immobilization onto an adhesive substrate and manipulation into arrays.

Biosilica of the diatom species Thalassiosira pseudonana is used as hard template for the synthesis of silicon carbide-derived carbons. The typical species-specific macroporous structure is retained during the nanocasting-chlorine treatment process and the resulting materials exhibit very high specific surface areas up to 2300 m g. Bioinspired carbons show very high capacities in mercury adsorption from aqueous solution compared to reference materials.

PREVIOUSLY HEALTHY 48-YEAR-OLD WOMAN was admitted to the hospital with acute hematemesis and melena. A physical examination revealed that she was in good general health without any abdominal tenderness or pain on palpation and normal bowel sounds. Her vital signs showed a slightly reduced blood pressure (120/70 mm Hg) with tachycardia of 110 beats/ min. Within a few hours, her hemoglobin concentration rapidly dropped from 111 g/L to 85 g/L and further to 74 g/L even after she received 2 red blood cell transfusions. An esophagogastroduodenoscopy did not show any bleeding lesions in the upper gastrointestinal (GI)

Alcohol adsorption by metal-organic frameworks (ZIF-8 and ZIF-11) in aqueous solutions is investigated including alcohol mixtures. Solid-state 13C NMR spectroscopy is demonstrated to be well-suited for such liquid-phase adsorption studies...