New Chiral Ligands: From Fundamental Research to Potential Industrial Applications

Asymmetric catalysis is one of the most extensively studied areas in chemistry over the past three decades. In this presentation we will discuss the new advancements in the design, synthesis, and application of chiral ligands used for catalytic reactions in our laboratory. Particular emphasis will be placed on new, highly efficient synthetic methodologies and their potential industrial applications.New Chiral Ligands: From Fundamental Research to Potential Industrial Applications@Albert S.…     

Stiff-Stilbene Photoswitches: From Fundamental Studies to Emergent Applications

Stiff-stilbene, a sterically restricted fused ring analogue of stilbene, has been regularly used as a model compound in theoretical studies of stilbene photoisomerization. Lately, owing to its excellent photoswitching properties, it is increasingly being applied to reversibly control the properties and function of chemical as well as biological systems. Stiff-stilbene photoswitches possess a number of advantageous properties including a high quantum yield for photoisomerization and a high thermal stability. Furthermore, they undergo a large geometrical change upon isomerization and their synthesis is straightforward. Herein, we provide an overview of the basic properties of stiff-stilbene and of recent applications in supramolecular chemistry, catalysis, and biological systems.     

Interfacial Properties of Hydrophobically Modified Biomolecules: Fundamental Aspects and Applications

This review describes the interfacial behavior of biomolecules, which were converted to more hydrophobic derivatives by covalent attachment of hydrophobic chains. The molecules presented are proteins (glucose oxidase, immunoglobulin G, gelatin, ovalbumin) and polysaccharides (carboxymethylcellulose, pullulan). In general, it was found that such hydrophobically modified biomolecules have enhanced surface activity and ability to penetrate into phospholipid monolayers. In addition, it has been demonstrated, that such molecules can be used as efficient emulsifiers and foaming agents, and in unique biomedical application based on combining the surface activity and recognition ability.

     

Stiff‐Stilbene Photoswitches: From Fundamental Studies to Emergent Applications

Stiff‐stilbene, a sterically restricted fused ring analogue of stilbene, has been regularly used as a model compound in theoretical studies of stilbene photoisomerization. Lately, owing to its excellent photoswitching properties, it is increasingly being applied to reversibly control the properties and function of chemical as well as biological systems. Stiff‐stilbene photoswitches possess a number of advantageous properties including a high quantum yield for photoisomerization and a high thermal stability. Furthermore, they undergo a large geometrical change upon isomerization and their synthesis is straightforward. Herein, we provide an overview of the basic properties of stiff‐stilbene and of recent applications in supramolecular chemistry, catalysis, and biological systems.     

Recent Advance in Carbon Dots:From Properties to Applications

As a new type of nanomaterial,carbon dots (CDs) have been recognized as a versatile nanoplatform with enormous potential for biomedical and op-toelectronic appl...     

New Catalysts of the Metal-Filamentary Carbon Type: From Fundamental Research to Technology

A principally new basic catalytic system is developed. The system is based on dispersed metal particles incorporated into carbon filaments by the catalytic decomposition of hydrocarbons on these particles. The basic system enables one to synthesize a series of catalysts for different processes. Mechanisms and methods for controlling the catalytic properties of this system are studied. The role of the crystal faces of the metal particles and of chemisorbed hydrogen species in selective hydrogenation is established. The chemical composition of the active component is optimized for the removal of acetylene from ethylene and of butadiene from butenes. A technology for catalyst precursor preparation is developed, which includes a mechanochemical activation stage and the shaping of the resulting powder. Optimum conditions are found for hydrocarbon decomposition in order to obtain metal-carbon catalysts for selective hydrogenation.     

Chelating Ligands Tethered to Carbon Nanotubes

Summary: Carbon nanotubes offer an inert platform on which various species may be supported. A range of applications have been addressed using this approach. Anchoring sites on the nanotubes are usually groups introduced via an oxidative procedure. These groups provide convenient reactive functionality that can be accessed in a variety of ways. In this case, carboxyl functionality have been utilized to attach, through a linker, a good coordinating ligands, 1-10-phenanthroline. In the first instance, 1,10-phenanthroline was converted to the 5,6-epoxide by treatment with hypochlorite. The epoxide was opened in sulfuric acid to generate the 5-hydroxy compound. This, in turn, was treated with ethylene oxide in the presence of a base to provide the alkoxylated compound. The alcohol terminus, as the alkoxide, was used to couple the nanotubes by displacement of tosyl anion from the methylol ester. The carboxyl groups at the nanotubes surface were reduced to the corresponding alcohol and treated with p-toluenesulfonyl chloride in the presence of pyridine to generate the tosylate used for coupling. In a second approach the carboxyl groups were converted to the corresponding acid chloride which was treated with alkoxylated phenanthroline to achieve coupling via an ester linkage.     

Fundamental Technological Approaches to the Synthesis of Carbon Sorbents for Medical and Veterinary Applications

Russian Journal of General Chemistry - Some approaches to the synthesis of various modified carbon sorbents developed at the Laboratory of Synthesis of Functional Carbon Materials, Institute of...     

DNA Switches: From Principles to Applications

The base sequence of nucleic acid encodes structural and functional properties into the biopolymer. Structural information includes the formation of duplexes, G‐quadruplexes, i‐motif, and cooperatively stabilized assemblies. Functional information encoded in the base sequence involves the strand‐displacement process, the recognition properties by aptamers, and the catalytic functions of DNAzymes. This Review addresses the implementation of the information encoded in nucleic acids to develop DNA switches. A DNA switch is a supramolecular nucleic acid assembly that undergoes cyclic, switchable, transitions between two distinct states in the presence of appropriate triggers and counter triggers, such as pH value, metal ions/ligands, photonic and electrical stimuli. Applications of switchable DNA systems to tailor switchable DNA hydrogels, for the controlled drug‐release and for the activation of switchable enzyme cascades, are described, and future perspectives of the systems are addressed.     

Ferroptosis Detection: From Approaches to Applications

Understanding the intricate molecular machinery that governs ferroptosis and leveraging this accumulating knowledge could facilitate disease prevention, diagnosis, treatment, and prognosis. Emerging approaches for the in situ detection of the major regulators and biological events across cellular, tissue, and in living subjects provide a multiscale perspective for studying ferroptosis. Furthermore, advanced applications that integrate ferroptosis detection and the latest technologies hold tremendous promise in ferroptosis research. In this review, we first briefly summarize the mechanisms and key regulators underlying ferroptosis. Ferroptosis detection approaches are then presented to delineate their design, mechanisms of action, and applications. Special interest is placed on advanced ferroptosis applications that integrate multifunctional platforms. Finally, we discuss the prospects and challenges of ferroptosis detection approaches and applications, with the aim of providing a roadmap for the theranostic development of a broad range of ferroptosis-related diseases.     

Stimuli-Responsive DNA Self-Assembly: From Principles to Applications

Stimuli-responsive DNA self-assembly shares the advantages of both designed stimuli-responsiveness and the molecular programmability of DNA structures, offering great opportunities for basic and applied research in dynamic DNA nanotechnology. In this minireview, we summarize the most recent progress in this rapidly developing field. The trigger mechanisms of the responsive DNA systems are first divided into six categories, which are then explained with illustrative examples following this classification. Subsequently, proof-of-concept applications in terms of biosensing, in vivo pH-mapping, drug delivery, and therapy are discussed. Finally, we provide some remarks on the challenges and opportunities of this highly promising research direction in DNA nanotechnology.     

From Binuclear Complexes to Molecular Necklaces: Incorporating Flexible Ligands into Rotaxanes

The conversion of binuclear complexes into larger molecular necklaces can be achieved through rigidifying flexible ligands by threading them through a crown ether to form either an interpenetrated [2]pseudorotaxane or a permanently interlocked [2]rotaxane. The resulting complexes and assemblies are characterized by ¹H and DOSY NMR in solution and single‐crystal X‐ray diffraction in the solid‐state.     

Phosphorus Heterocycles: From Laboratory Curiosities to Ligands in Highly Efficient Catalysts

Phosphabenzenes and phosphaferrocenes were among the first compounds with P−C multiple bonds. For nearly 30 years the chemistry of these molecules was essentially a domain left to basic researchers. Recently, however, it was reported that transition metal complexes with phosphabenzene and phosphaferrocene ligands exhibit remarkable potential as catalysts. Catalysts based on rhodium (I ) and various phosphabenzenes appear to be superior to classical systems in the hydroformylation of terminal and internal alkenes. In addition planar‐chiral phosphaferrocene species display an excellent performance as directing ligands in a series of enantioselective asymmetric syntheses.     

Redox‐functionalized Ligands: From Molecular Electrochemical Sensors to Nanostructured Surfaces

The modification of ligands by functional groups can lead to novel, emergent ligand properties. Our group has focussed on bi‐ and tridentate N donor ligands which contain redox‐active groups derived from either ferrocene or cyclopentadienone. The present report describes the use of these modified ligands in diverse fields of application, ranging from molecular coordination chemistry to materials science.     

ESEM Applications: From Cultural Heritage Conservation to Nano-Behaviour

The application of ESEM technology to the conservation of cultural heritage and other fields is reviewed. Several applications are presented with a focus on reaction kinetics and micro to nano-scale material behaviours, including time-lapse studies of reaction kinetics for NaCl and NaNO₃; verification of the stone decay mechanism at the site of Copan, Honduras; and ESEM/EDS analysis of the first photograph (1826). A review of other ESEM applications reveals some important trends, especially in the materials science, electronics and biosciences fields, such as quantitative ESEM/EDS; 1.8 nm resolution imaging of extreme insulators in VP/ESEM; and ESEM analysis of emulsions and cells.     

Designing State-of-the-Art Gas Sensors: From Fundamentals to Applications

Gas sensors are crucial in environmental monitoring, industrial safety, and medical diagnostics. Due to the rising demand for precise and reliable gas detection, there is a rising demand for cutting-edge gas sensors that possess exceptional sensitivity, selectivity, and stability. Due to their tunable electrical properties, high-density surface-active sites, and significant surface-to-volume ratio, nanomaterials have been extensively investigated in this regard. The traditional gas sensors utilize homogeneous material for sensing where the adsorbed surface oxygen species play a vital role in their sensing activity. However, their performance for selective gas sensing is still unsatisfactory because the employed high temperature leads to the poor stability. The heterostructures nanomaterials can easily tune sensing performance and their different energy band structures, work functions, charge carrier concentration and polarity, and interfacial band alignments can be precisely designed for high-performance selective gas sensing at low temperature. In this review article, we discuss in detail the fundamentals of semiconductor gas sensing along with their mechanisms. Further, we highlight the existed challenges in semiconductor gas sensing. In addition, we review the recent advancements in semiconductor gas sensor design for applications from different perspective. Finally, the conclusion and future perspectives for improvement of the gas sensing performance are discussed.     

Triplex DNA Nanostructures: From Basic Properties to Applications

Triplex nucleic acids have recently attracted interest as part of the rich “toolbox” of structures used to develop DNA‐based nanostructures and materials. This Review addresses the use of DNA triplexes to assemble sensing platforms and molecular switches. Furthermore, the pH‐induced, switchable assembly and dissociation of triplex‐DNA‐bridged nanostructures are presented. Specifically, the aggregation/deaggregation of nanoparticles, the reversible oligomerization of origami tiles and DNA circles, and the use of triplex DNA structures as functional units for the assembly of pH‐responsive systems and materials are described. Examples include semiconductor‐loaded DNA‐stabilized microcapsules, DNA‐functionalized dye‐loaded metal–organic frameworks (MOFs), and the pH‐induced release of the loads. Furthermore, the design of stimuli‐responsive DNA‐based hydrogels undergoing reversible pH‐induced hydrogel‐to‐solution transitions using triplex nucleic acids is introduced, and the use of triplex DNA to assemble shape‐memory hydrogels is discussed. An outlook for possible future applications of triplex nucleic acids is also provided.