Three porous polymer networks (PPNs) have been synthesized by the homocoupling of tetrahedral monomers. Like other hyper-cross-linked polymer networks, these materials are insoluble in conventional solvents and exhibit high thermal and chemical stability. Their porosity was confirmed by N2 sorption isotherms at 77 K. One of these materials, PPN-3, has a Langmuir surface area of 5323 m2 g−1. Their clean energy applications, especially in H2, CH4, and CO2 storage, as well as CO2/CH4 separation, have been carefully investigated. Although PPN-1 has the highest gas affinity because of its smaller pore size, the maximal gas uptake capacity is directly proportional to their surface area. PPN-3 has the highest H2 uptake capacity among these three (4.28 wt %, 77 K). Although possessing the lowest surface area, PPN-1 shows the best CO2/CH4 selectivity among them.

Supercritical fluid reactive deposition was used for the deposition of highly dispersed platinum nanoparticles with controllable metal content and particle size distribution on beta-cyclodextrin. The average particle size and size distribution were steered by the precursor reduction conditions, resulting in particle preparations <20, <100, and >100 nm as characterized by transmission electron microscopy and scanning electron microscopy (SEM). These particle preparations of different size distributions were used to address the question as to whether metallic platinum particles are able to invade cells of the gastrointestinal tract as exemplified for the human colon carcinoma cell line HT29 and thus affect the cellular redox status and DNA integrity. Combined focused ion beam and SEM demonstrated that platinum nanoparticles were taken up into HT29 cells in their particulate form. The chemical composition of the particles within the cells was confirmed by energy-dispersive X-ray spectroscopy. The potential influence of platinum nanoparticles on cellular redoxsystems was determined in the DCF assay, on the translocation of Nrf-2 and by monitoring the intracellular glutathione (GSH) levels. The impact on DNA integrity was investigated by single cell gel electrophoresis (comet assay) including the formation of sites sensitive to formamidopyrimidine-DNA-glycosylase. Platinum nanoparticles were found to decrease the cellular GSH level and to impair DNA integrity with a maximal effect at 1 ng/cm(2). These effects were correlated with the particle size in an inverse manner and were enhanced with increasing incubation time but appeared not to be based on the formation of reactive oxygen species.

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Tetrahedral DNA hybrids with tetrakis(p-hydroxyphenyl)methane cores hybridize in a sequence-specific fashion at much higher temperatures than isolated linear duplexes. Dinucleotide DNA arms suffice to induce the formation of a solid at room temperature; this demonstrates the strength of multivalent binding. The graphic shows a view of a modeled assembly.

Front Cover: Complex star polymer architectures are constructed for the first time via supramolecular self‐assembly driven by Hamilton wedge and cyanuric acid recognition units based on a scaffold generated by click chemistry. Further details can be found in the article by O. Altintas, T. Muller, E. Lejeune, O. Plietzsch, S. Bräse,* and C. Barner‐Kowollik* .

A modular concept for the generation of achiral and chiral non-racemic tetrahedral tectons from common precursors was developed. The tectons presented here are based on tetraphenylmethane or 1,3,5,7-tetraphenyladamantane core structures. They are obtained through high-yielding four-fold click reactions, using either the tetraazido or the tetraalkyne precursors. In most cases, the tetratriazoles are obtained as pure products after simple washing with water and methanol. The side chains of the tectons prepared include a self-complementary DNA dimer, obtained from a 3'-azidonucleoside and a phosphoramidite. The concept allows for a variation of the "sticky ends", leading to tecton or ligand libraries.

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Click the CMPs and POPs: The Huisgen 1,3‐dipolar cycloaddition reaction can be used to generate covalent porous organic materials such as conjugated microporous polymers (CMPs) and porous organic polymers (POPs). A triazole‐linked network based on complementary tetrahedral monomers has been prepared by means of click chemistry.