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Microscopic Submarines for Your Stomach: Micromotors neutralize gastric acid and release drugs depending on pH
Tiny “submarines” that speed independently through the stomach, use gastric acid for fuel (while rapidly neutralizing it), and release their cargo precisely at the desired pH: Though it may sound like science fiction, this is a new method for treating stomach diseases with acid-sensitive drugs introduced by scientists in the journal Angewandte Chemie. The technique is based on proton-driven micromotors with a pH-dependent polymer coating that can be loaded with drugs.
Tough Aqua Material for Water Purification: Decontamination of water with a robust and sustainable membrane assembled from two synergistically working components
Water purification processes usually make use of robust membranes for filtering off contaminants while working at high pressures. Can materials employing water as major component be made strong enough to suit such a demanding application? Israeli scientists now report in the journal Angewandte Chemie that a supramolecular aqua material can be utilized as a sustainable membrane for water purification at high pressures.
Composite Material for Water Purification: Removal of multiple contaminants from water by supported ionic liquid phases
Fresh, clean water coming directly from the tap is a true luxury. In developing countries, people often have no choice but to use a contaminated river for drinking water. Water filters can help by quickly converting polluted surface or ground water into safe drinking water. In the journal Angewandte Chemie, researchers have now introduced a novel multifunctional composite material that removes inorganic, organic, radioactive, and microbial impurities from water.
Speeding Up 19th Century Oil Paintings: Lead acetate and mastic resin in paint mixtures helped artists 200 years ago
The fluid and loose brushwork used by J.W.M. Turner and other innovative 19th century artists to capture the momentary effects of light was technically made possible by the addition of "gumtion" or "megilp" to the paint matrix, which gave the paints the jelly-like consistency needed for their impasto-rich paintwork. In the journal Angewandte Chemie, scientists unveil the crucial role lead acetate played in this gelation process.
Harmonization Needed! Standardized analytic protocols will help to assess the amount, quality, and risk of microplastic contaminants in aquatic ecosystems, says a review
Since the first reports on a dramatic increase in microplastic contamination in the sea twenty years ago, research efforts have intensified worldwide. A review in the journal Angewandte Chemie has critically evaluated these studies and concludes that the analytical methods have to be harmonized to get comparable data. Further development is needed to assess particles in the lower micrometer range and below as well, as these pose the highest risks for aquatic ecosystems.
Anti-Tumor Synergy: Nanomedical treatment concept combines NO gas therapy with starvation of tumor cells
Biocompatible nanocapsules, loaded with an amino acid and equipped with an enzyme now combine two anti-tumor strategies into a synergistic treatment concept. Researchers hope this increases effectiveness and decreases side effects. In the journal Angewandte Chemie, the scientists explain the concept: tumor cells are deprived of their nutrient glucose as this is converted to toxic nitrogen monoxide (NO) and hydrogen peroxide (H2O2).
Hydrogen from Sunlight—But As a Dark Reaction: Generation, storage, and time-delayed release of electrons in graphitic carbon nitride material for artificial photosynthesis
The storage of photogenerated electric energy and its release on demand are still among the main obstacles in artificial photosynthesis. One of the most promising, recently identified photocatalytic new materials is inexpensive graphitic carbon nitride. Scientists have now explored a modified form that can produce light-generated electrons and store them for catalytic hydrogen production even after the light has been switched off. They present this biomimetic photosynthesis approach in the journal Angewandte Chemie.
Polymerization by chemical vapor deposition (CVD) is a simple method for modifying surfaces by which topologically challenging substrates can be evenly coated with polymers. In the journal Angewandte Chemie, researchers have now introduced the first CVD method for producing degradable polymers. Biomolecules or drugs can be attached by means of special side groups. This introduces new possibilities for applications like the coating of biodegradable implants.
Light Switch in Autumn Leaves: Yellow chlorophyll decomposition products are environment-responsive photoswitches
Before trees lose their leaves in the winter, they offer us a bright autumnal display of reds, oranges, and yellows. This results from the decomposition of the compound that makes leaves green: chlorophyll. Among the decomposition products are yellow phyllobilins that demonstrate unusual chemical properties. As reported by Austrian scientists in the journal Angewandte Chemie, these compounds act as four-step molecular “switches” that are triggered by light in different ways depending on the environment.
Implantable Catalyst Against Cancer: Biocompatible heterogeneous copper catalyst for click chemistry in living organisms
Assembling a drug from harmless components at the target location, such as a tumor, would help reduce the side effects of treatment. In the journal Angewandte Chemie, British and Malaysian scientists present a new, nontoxic catalyst made of copper nanoparticles that can be used to specifically and selectively assemble building blocks in a living system. It was shown to be possible to make an anti-tumor drug from two benign components in situ.
Safe Fog: Phosphorus nitride could be used as a friction-stable, fast-burning, and very effective pyrotechnic obscurant
Safety combined with power and effectiveness is one of the most important targets in the development of pyrotechnic obscurants. In the journal Angewandte Chemie, German and Polish scientists introduced phosphorus nitride as a safe but very powerful alternative to the well-known red phosphorus formulations, which have been used in military and civilian applications for decades.
Salty Batteries: Sodium-oxygen batteries have improved cycle life due to highly concentrated electrolytes
Smartphones, laptops, electric cars—whatever the device, an efficient battery is high on any user’s wish list. The search for the next-generation battery has recently focused on sodium– oxygen batteries. Theoretically, these should provide previously unattainable efficiency but their practical implementation has proven to be a stumbling block. Researchers now report in the journal Angewandte Chemie, that a highly concentrated electrolyte solution may make the sodium–oxygen battery more stable, and therefore more practicable.
Lithium Ion Extraction: A combined polymer/metal–organic composite membrane allows for the effective separation of lithium from contaminants in brines
The increasing usage of lithium for batteries or high-performance metals requires improved extraction techniques of lithium from primary sources such as salt lake brines. Chinese scientists have now designed a solid composite membrane that combines the mimicking of the chemical selection process in biological ion channels with molecular sieve technology. In the journal Angewandte Chemie, they report the effective and fast separation of lithium ions from brines with that membrane.
Fighting the Gram-Negatives: Natural products inspire the design of molecular agents against drug-resistant bacterial strains
Many microorganisms produce secondary natural products, the potential antibiotic effects of which are extensively investigated. German scientists have now examined a class of quinone-like substances containing an additional epoxide functional group for their antibiotic activities. As they report in the journal Angewandte Chemie, the compounds can kill problematic Salmonella pathogens, probably by interfering with their bacterial stress response system.
Directed motion seems simple to us, but the coordinated interplay of complex processes is needed, even for seemingly simple crawling motions of worms or snails. By using a gel that periodically swells and shrinks, researchers developed a model for the waves of muscular contraction and relaxation involved in crawling. As reported in the journal Angewandte Chemie, they were able to produce two types of crawling motion by using inhomogeneous irradiation.
Where Does Cisplatin Bind?: Identification of genome-wide cisplatin cross-linking sites with DNA base resolution
Cisplatin is one of the most widely used agents in cancer chemotherapy. Its mode of action is cross-linking of the DNA, which can kill cells. But which part of the genome is more affected, and which is less affected? A Chinese team of scientists have now set up a universal, genome-wide assay system to detect the specific cisplatin action sites, In the journal Angewandte Chemie the scientists introduce their system and report initial results, which support the notion that the mitochondrial genome is one of cisplatin's main targets.
John Wiley & Sons, Inc., (NYSE: JWa, JWb) would like to acknowledge the laureates honored with the 2016 Nobel Prize. Six of these laureates have had their work published in Wiley’s medical, physiology, chemistry and economics journals and books.
Self-Healable Battery: Lithium ion battery for electronic textiles grows back together after breaking
Electronics that can be embedded in clothing are a growing trend. However, power sources remain a problem. In the journal Angewandte Chemie, scientists have now introduced thin, flexible, lithium ion batteries with self-healing properties that can be safely worn on the body. Even after completely breaking apart, the battery can grow back together without significant impact on its electrochemical properties.
Hidden Chirality: Nitrogen-15 isotope can trigger asymmetric autocatalytic reactions toward chiral organic compounds
The preparation of chiral compounds as intermediates in drug synthesis is one of the most important targets in synthetic organic chemistry. Japanese scientists have now shown that the autocatalytic preparation of a chiral intermediate can be triggered by a compound bearing hidden chirality, which consisted of nothing more than the difference between the isotopes nitrogen-15 and nitrogen-14. The study is published in the journal Angewandte Chemie.
Catalyst from the Microwave: Microwave-assisted thermolysis: New route to highly crystalline carbon nitrides for efficient photocatalytic hydrogen generation
Lunch out of the microwave usually doesn’t taste nearly as good as a meal made in a conventional oven. This difference in quality is reversed for graphitic carbon nitride, a catalyst used for generating hydrogen from sunlight. Treatment of a precursor material with microwaves delivers a significantly more crystalline product than conventional thermolysis in an oven. As scientists report in the journal Angewandte Chemie, a catalyst produced in this way is significantly more effective in the generation of hydrogen.