Search Results (14)

The limitations of conventional inorganic electrodes call for organic alternatives for advanced energy storage. Metal–covalent organic frameworks (MCOFs) integrate the metal active sites of metal–organic frameworks (MOFs) with the high chemical stability imparted by strong covalent bonds in covalent organic frameworks (COFs) while retaining the high specific surface area and tunable porosity of both material classes. Among these, MCOFs constructed from porphyrin and phthalocyanine building units have emerged as a research hotspot in electrochemical energy storage owing to their inherent 18π-conjugated macrocyclic electronic systems, well-defined M–N₄ coordination sites, and potential bipolar charge storage characteristics. This review systematically summarizes recent advances in this class of materials. First, from the perspective of metal center introduction timing, three core synthetic strategies—pre-metallation, simultaneous metallation, and post-metallation—are categorized and evaluated in terms of coordination precision, synthetic efficiency, and scalability potential. Second, the regulatory effects of two-dimensional layered and three-dimensional interpenetrated structures on charge transport pathways and structural stability are elucidated. Subsequently, the applications of porphyrin/phthalocyanine-based MCOFs in lithium-based batteries, zinc-based batteries, sodium/potassium-ion batteries, and supercapacitors are reviewed in detail, with emphasis on the key roles of metal active sites in catalytic conversion, chemical anchoring/confinement, interface stabilization, and pseudocapacitive contribution. Finally, future directions to address key performance and mechanistic bottlenecks are discussed. This review aims to provide a systematic reference for the rational design and energy storage applications of high-performance porphyrin/phthalocyanine-based MCOFs. Full article

In recent years, metal phthalocyanine (MPc)-based sensors have garnered significant interest for applications in environmental monitoring, biomedical diagnostics, and industrial process control, owing to their efficient and cost-effective sensing capabilities. In contrast to conventional inorganic materials, MPcs are a class of small-molecule materials characterized by a stable, π-conjugated macrocyclic framework with a tunable central metal ion. This structural architecture imparts unique physicochemical properties, including high chemical stability, excellent redox activity, structural versatility, considerable dielectric constant and electrical conductivity, along with pronounced optical absorption and excellent environmental stability. By incorporating different metal ions into the macrocyclic core, their functional characteristics can be precisely modulated to achieve high sensitivity and selectivity toward various gas, ion, or biomolecule targets. Leveraging these advantages, MPcs have been extensively utilized in diverse sensing platforms, such as photoelectric, gas, and biosensors. This review outlines recent advances in MPc-based sensor research and provides perspectives on their future development trends. Full article

Redox mediators are central to electrochemical biosensors, enabling electron transfer between deeply buried enzymatic cofactors and electrode surfaces when direct electron transfer is kinetically inaccessible. Among all design parameters, the reversibility of mediator redox cycling remains the most decisive yet under-examined factor governing biosensor stability, drift and long-term reproducibility. This review establishes reversibility as a unifying framework grounded in inorganic and organometallic redox chemistry, with particular emphasis on coordination environments, ligand-field effects and outer-sphere electron-transfer pathways. Recent advances (2010–2025) in ruthenium and osmium polypyridyl complexes, cobalt macrocycles, hexacyanoferrates and Prussian Blue analogues are examined alongside ferrocene derivatives and other organometallic mediators, which together define the upper limits of reversible behaviour. Organic mediator families, including quinones, phenazines, indophenols, aminophenols and viologens, are discussed as mechanistic contrasts that highlight the structural and thermodynamic constraints that limit long-term cycling in aqueous media. Mechanistic indicators of reversibility, including peak separation, current ratios and heterogeneous electron-transfer rate constants, are linked to mediator architecture, coordination chemistry and immobilisation environment. By integrating molecular electrochemistry with applied sensor engineering, this review provides a mechanistically grounded basis for selecting or designing redox mediators that sustain efficient electron transfer, minimal fouling and calibration stability across diverse sensing platforms. Full article

In this short review, recent findings from both theory and experiment regarding the process of hydration of α-, β-, and γ-cyclodextrins are summarized and critically assessed. Key important questions are addressed, including: What factors govern the number of water molecules entrapped in the internal cavity of the host macrocycle? What is the driving force behind this process? What are the “hot spots” for water entrapment inside the host cavity? What is the underlying mechanism of water hydration and dehydration of cyclodextrins? What is the role of the confined water cluster in determining the outcome of the host–guest complexation between cyclodextrins and molecules of inorganic/organic nature? To what extent does water hydration affect the crystalline structure of the cavitand? Full article

A comprehensive thermodynamic and structural study of the complexation affinities of tetra (L1), penta (L2), and hexaphenylalanine (L3) linear peptides towards several inorganic anions in acetonitrile (MeCN) and N,N-dimethylformamide (DMF) was carried out. The influence of the chain length on the complexation thermodynamics and structural changes upon anion binding are particularly addressed here. The complexation processes were characterized by means of spectrofluorimetric, ¹H NMR, microcalorimetric, and circular dichroism spectroscopy titrations. The results indicate that all three peptides formed complexes of 1:1 stoichiometry with chloride, bromide, hydrogen sulfate, dihydrogen phosphate (DHP), and nitrate anions in acetonitrile and DMF. In the case of hydrogen sulfate and DHP, anion complexes of higher stoichiometries were observed as well, namely those with 1:2 and 2:1 (peptide:anion) complexes. Anion-induced peptide backbone structural changes were studied by molecular dynamic simulations. The anions interacted with backbone amide protons and one of the N-terminal amine protons through hydrogen bonding. Due to the anion binding, the main chain of the studied peptides changed its conformation from elongated to quasi-cyclic in all 1:1 complexes. The accomplishment of such a conformation is especially important for cyclopeptide synthesis in the head-to-tail macrocyclization step, since it is most suitable for ring closure. In addition, the studied peptides can act as versatile ionophores, facilitating transmembrane anion transport. Full article

Helminth parasitic infections are a considerable constraint to the livestock industries worldwide. Nematode parasites cause the major proportion of harm to livestock. The infections caused are accountable for severe economic losses in cattle, goat and sheep farming industries. Morbidity and mortality in livestock due to parasitic diseases are increasing alarmingly. Also, their zoonotic influence on human health is considered significant. Anthelmintic drugs have been developed occasionally to curb this disease and prevent major losses. But the development of resistance against these drugs has put another constraint on this flourishing industry. Helminth parasites have developed resistance against three main classes of anthelmintics: benzimidazoles, macrocyclic lactones and nicotinic agonists. With the intensification of resistance, various screening and confirmatory tests have been developed for the speedy introduction of newer drugs in the livestock industry. At the same time, designing and launching novel anthelmintics is time-consuming and economically restrained. Phytochemicals attract much attention because of their pharmacotherapeutic potential, least toxic profile and low environmental hazards. A lot of work is going on plant-based anthelmintic drugs throughout the world. Plants possessing anthelmintic activity have been found efficacious against gastrointestinal parasites. Nevertheless, these herbal medicines have various drawbacks, which include poor efficacy and the absence of target selectivity. These problems are now being taken care of with the help of nanotechnology. Nanoparticles improve the drug’s effectiveness, enhance drug delivery, and target selectivity at specific sites. A comprehensive literature survey was carried out via electronic searches of Google Scholar, PubMed, MEDLINE, Science Direct, Scopus and Cochrane Library databases and based on inclusion and exclusion criteria; articles were selected for this review. The review aims at providing a comprehensive overview of plant-based nanoparticles as therapeutic alternatives over conventional synthetic anthelmintic drugs. It also encompasses the methods of detection of resistance and the ways to overcome this menace. The effectiveness of various organic and inorganic nanoparticles against helminthes is also discussed in this review. Full article

Since their discovery in 2008 by N. Ogoshi and co-authors, pillararenes (PAs) have become popular hosts for molecular recognition and supramolecular chemistry, as well as other practical applications. The most useful property of these fascinating macrocycles is their ability to accommodate reversibly guest molecules of various kinds, including drugs or drug-like molecules, in their highly ordered rigid cavity. The last two features of pillararenes are widely used in various pillararene-based molecular devices and machines, stimuli-responsive supramolecular/host–guest systems, porous/nonporous materials, organic–inorganic hybrid systems, catalysis, and, finally, drug delivery systems. In this review, the most representative and important results on using pillararenes for drug delivery systems for the last decade are presented. Full article

Host–guest assemblies open up opportunities for developing novel functional CLUSPOM multicomponent systems based on transition metal clusters (CLUS), polyoxometalates (POMs) and macrocyclic organic ligands. In water–ethanol solution γ-cyclodextrin (γ-CD) interacts with halide metal clusters [M₆Cl₁₄]^2– (M = Mo, W) to form sandwich-type structures. The supramolecular association between the clusters and CDs, however, remains weak in solution, and the interactions are not strong enough to prevent the hydrolysis of the inorganic guest. Although analysis of the resulting crystal structures reveals inclusion complexation, ¹H NMR experiments in solution show no specific affinity between the two components. The luminescent properties of the host–guest compounds in comparison with the initial cluster complexes are also studied to evaluate the influence of CD. Full article

An intriguing but rare silicon-centered spirocyclic compound, spiro[5.5]octaferrocenylpentasiloxane (4) featuring silicon fused six-membered ferrocenyl-functionalized siloxane rings, has been obtained during the thermally induced transformation of triferrocenylsilane Fc₃Si–H (1) into triferrocenylsilanol Fc₃Si–OH (2), when N,N-dimethylformamide (DMF) was used as a solvent in the presence of the metal carbonyl Mo(CO)₆. The unexpected formation of the maximally ferrocenyl substituted silicon centered spirocyclic 4 involves the obtention, and subsequent condensation, of different ferrocenylsilanol intermediates. Spirocyclic silicate 4 has been characterized using a combination of MALDI-TOF mass spectrometry, elemental analysis, and single crystal X-ray diffraction analysis. Full article

Copper-containing agents are promising antitumor pharmaceuticals due to the ability of the metal ion to react with biomolecules. In the current study, we demonstrate that inorganic Cu²⁺ in the form of oxide nanoparticles (NPs) or salts, as well as Cu ions in the context of organic complexes (oxidation states +1, +1.5 and +2), acquire significant cytotoxic potency (2–3 orders of magnitude determined by IC₅₀ values) in combinations with N-acetylcysteine (NAC), cysteine, or ascorbate. In contrast, other divalent cations (Zn, Fe, Mo, and Co) evoked no cytotoxicity with these combinations. CuO NPs (0.1–1 µg/mL) together with 1 mM NAC triggered the formation of reactive oxygen species (ROS) within 2–6 h concomitantly with perturbation of the plasma membrane and caspase-independent cell death. Furthermore, NAC potently sensitized HCT116 colon carcinoma cells to Cu–organic complexes in which the metal ion coordinated with 5-(2-pyridylmethylene)-2-methylthio-imidazol-4-one or was present in the coordination sphere of the porphyrin macrocycle. The sensitization effect was detectable in a panel of mammalian tumor cell lines including the sublines with the determinants of chemotherapeutic drug resistance. The components of the combination were non-toxic if added separately. Electrochemical studies revealed that Cu cations underwent a stepwise reduction in the presence of NAC or ascorbate. This mechanism explains differential efficacy of individual Cu–organic compounds in cell sensitization depending on the availability of Cu ions for reduction. In the presence of oxygen, Cu⁺¹ complexes can generate a superoxide anion in a Fenton-like reaction Cu⁺¹L + O₂ → O₂^−. + Cu⁺²L, where L is the organic ligand. Studies on artificial lipid membranes showed that NAC interacted with negatively charged phospholipids, an effect that can facilitate the penetration of CuO NPs across the membranes. Thus, electrochemical modification of Cu ions and subsequent ROS generation, as well as direct interaction with membranes, represent the mechanisms of irreversible membrane damage and cell death in response to metal reduction in inorganic and organic Cu-containing compounds. Full article

The development of hybrid materials based on polyoxometalates constitutes a strategy for the design of multifunctional materials. The slow evaporation of an aqueous solution of [NaP₅W₃₀O₁₁₀]¹⁴⁻ in the presence of γ-Cyclodextrin (γ-CD) led to the crystallization of a K₆Na₈{[NaP₅W₃₀O₁₁₀]•(C₄₈H₈₀O₄₀)}•23H₂O (NaP₅W₃₀•1CD) supramolecular compound, which was characterized by single-crystal X-ray diffraction, IR-spectroscopy, thermogravimetric and elemental analyses. Structural analysis revealed the formation of 1:1 {[NaP₅W₃₀O₁₁₀]•[γ-CD]}¹⁴⁻ adduct in the solid state. Studies in solution by cyclic voltammetry, electrochemical impedance spectroscopy, ¹H NMR spectroscopy, and ³¹P DOSY, have demonstrated weak interactions between the inorganic anion and the macrocyclic organic molecule. Full article

Encapsulation of cargoes in nanocontainers is widely used in different fields to solve the problems of their solubility, homogeneity, stability, protection from unwanted chemical and biological destructive effects, and functional activity improvement. This approach is of special importance in biomedicine, since this makes it possible to reduce the limitations of drug delivery related to the toxicity and side effects of therapeutics, their low bioavailability and biocompatibility. This review highlights current progress in the use of lipid systems to deliver active substances to the human body. Various lipid compositions modified with amphiphilic open-chain and macrocyclic compounds, peptide molecules and alternative target ligands are discussed. Liposome modification also evolves by creating new hybrid structures consisting of organic and inorganic parts. Such nanohybrid platforms include cerasomes, which are considered as alternative nanocarriers allowing to reduce inherent limitations of lipid nanoparticles. Compositions based on mesoporous silica are beginning to acquire no less relevance due to their unique features, such as advanced porous properties, well-proven drug delivery efficiency and their versatility for creating highly efficient nanomaterials. The types of silica nanoparticles, their efficacy in biomedical applications and hybrid inorganic-polymer platforms are the subject of discussion in this review, with current challenges emphasized. Full article

As is known, in the last fifty years of coordination of inorganic and organo-elemental chemistry, chemical compounds formed by chelating or macrocyclic organic and organo-elemental ligands (in particular, crown ethers, cryptands, calixarenes, cucurbituryls, porphyrins, and their various derivatives) and ions of various p-, d- and f-elements, have become of special interest [...] Full article

A novel inorganic-organic hybrid supramolecular macrocyclic compound, (4-nitroanilinium)(18-crown-6)(PF₆)(1), was synthesized and characterized by infrared spectroscopy, thermogravimetric analysis, elemental analysis, differential scanning calorimetry (DSC), and single-crystal X-ray diffraction. Crystal 1 is found to comprise 1D C–H···F–P hydrogen-bonded chains of (4-nitroanilinium⁺)(18-crown-6) supramolecular cations and PF₆⁻ anions. DSC measurements confirm that 1 undergoes a reversible phase transition at 255 K with a hysteresis width of 6 K. A strong dielectric response is observed above 250 K at a low frequency (500 Hz), suggesting the occurrence of proton transfer in the C–H···F–P hydrogen bonds. A precise analysis on the main packing and structural differences, as well as the changes in the intermolecular interaction between the low- and high-temperature phases, reveals that C–H···F–P hydrogen bonds are the main factors affecting phase transition and dielectric behavior. Full article