Dispersion Size-Consistency

A multivariate adiabatic connection (MAC) framework for describing dispersion interactions in a system consisting of non-overlapping monomers is presented. By constraining the density to the physical ground-state density of the supersystem, the MAC enables a rigorous separation of induction and dispersion effects. The exact dispersion energy is obtained from the zero-temperature fluctuation-dissipation theorem and partitioned into increments corresponding to the interaction energy gained when an additional monomer is added to a -monomer system. The total dispersion energy of an -monomer system is independent of any partitioning into subsystems. This statement of dispersion size consistency is shown to be an exact constraint. The resulting additive separability of the dispersion energy results from multiplicative separability of the generalized screening factor defined as the inverse generalized dielectric function. Many-body perturbation theory (MBPT) is found to violate dispersion size-consistency because perturbative approximations to the generalized screening factor are nonseparable; on the other hand, random phase approximation-type methods produce separable generalized screening factors and therefore preserve dispersion size-consistency. This result further explains the previously observed increase in relative errors of MBPT for dispersion interactions as the system size increases. Implications for electronic structure theory and applications to supramolecular materials and condensed matter are discussed.

Supramolecular assemblies of organo-functionalised hybrid polyoxometalates: from functional building blocks to hierarchical nanomaterials

Organic–inorganic hybrid polyoxometalates are versatile building blocks for the self-assembly of functional supramolecular materials.

Enabling Technology for Supramolecular Chemistry

Supramolecular materials–materials that exploit non-covalent interactions–are increasing in structural complexity, selectivity, function, stability, and scalability, but their use in applications has been comparatively limited. In this Minireview, we summarize the opportunities presented by enabling technology–flow chemistry, high-throughput screening, and automation–to wield greater control over the processes in supramolecular chemistry and accelerate the discovery and use of self-assembled systems. Finally, we give an outlook for how these tools could transform the future of the field.

Evolution of Supramolecular Systems Towards Next-Generation Biosensors

Supramolecular materials, which rely on dynamic non-covalent interactions, present a promising approach to advance the capabilities of currently available biosensors. The weak interactions between supramolecular monomers allow for adaptivity and responsiveness of supramolecular or self-assembling systems to external stimuli. In many cases, these characteristics improve the performance of recognition units, reporters, or signal transducers of biosensors. The facile methods for preparing supramolecular materials also allow for straightforward ways to combine them with other functional materials and create multicomponent sensors. To date, biosensors with supramolecular components are capable of not only detecting target analytes based on known ligand affinity or specific host-guest interactions, but can also be used for more complex structural detection such as chiral sensing. In this Review, we discuss the advancements in the area of biosensors, with a particular highlight on the designs of supramolecular materials employed in analytical applications over the years. We will first describe how different types of supramolecular components are currently used as recognition or reporter units for biosensors. The working mechanisms of detection and signal transduction by supramolecular systems will be presented, as well as the important hierarchical characteristics from the monomers to assemblies that contribute to selectivity and sensitivity. We will then examine how supramolecular materials are currently integrated in different types of biosensing platforms. Emerging trends and perspectives will be outlined, specifically for exploring new design and platforms that may bring supramolecular sensors a step closer towards practical use for multiplexed or differential sensing, higher throughput operations, real-time monitoring, reporting of biological function, as well as for environmental studies.

Structural Diversity of Hydrogen-Bonded 4-Aryl-3,5-Dimethylpyrazoles for Supramolecular Materials

The 1H-pyrazoles have high versatility and ability to form hydrogen-bonded supramolecular materials. In this study, the thermal stability, fluorescence, and H-bonding ability of the studied 3,5-dimethyl-4-(4-X-phenyl)-1H-pyrazoles showed large differences depending on the terminal substituent. Supramolecular structures were analyzed using X-ray diffraction and Hirshfeld surface calculations. Compounds were found to arrange in different hydrogen-bonded structures, depending on the substitution at the para position of the phenyl ring (X = OCH3, NO2, NH2). The methoxy-substituted compounds arranged in dimers through methanol bridges, the nitro-substituted compound formed supramolecular polymers or catemers, and the amino-substituted compound gave rise to a new structure based on a 2D hydrogen-bonded network.

Exploiting Peptide Self-Assembly for the Development of Minimalistic Viral Mimetics

Viruses are natural supramolecular nanostructures that form spontaneously by molecular self-assembly of complex biomolecules. Peptide self-assembly is a versatile tool that allows mimicking viruses by creating their simplified versions through the design of functional, supramolecular materials with modularity, tunability, and responsiveness to chemical and physical stimuli. The main challenge in the design and fabrication of peptide materials is related to the precise control between the peptide sequence and its resulting supramolecular morphology. We provide an overview of existing sequence patterns employed for the development of spherical and fibrillar peptide assemblies that can act as viral mimetics, offering the opportunity to tackle the challenges of viral infections.

Biomedical Applications of Supramolecular Materials in the Controllable Delivery of Steroids

Glucocorticoids are a class of steroid hormones secreted from the adrenal glands. The strong anti-inflammatory effects make it be one of the most popular and versatile drugs available to treat chronic inflammatory diseases. Additionally, supramolecular materials have been widely exploited in drug delivery, due to their biocompatibility, tunability, and predictability. Thus, steroid-based supramolecular materials and the release of steroids have been applied in the treatment of inflammatory diseases. This mini-review summarized recent advances in supramolecular materials loaded with glucocorticoid drugs in terms of hydrophobic interactions, electrostatic interactions, hydrogen bonding, and π-π stackings. We also discussed and prospected the application of the glucocorticoid drugs-based supramolecular system on chronic rhinosinusitis, multifactorial inflammatory disease of the nasal and paranasal sinuses mucosal membranes. Overall, supramolecular materials can provide an alternative to traditional materials as a novel delivery platform in clinical practice.

Metal Cation Triggered Peptide Hydrogels and Their Application in Food Freshness Monitoring and Dye Adsorption

Metal-ligand interactions have emerged as an important tool to trigger and modulate self-assembly, and to tune the properties of the final supramolecular materials. Herein, we report the metal-cation induced self-assembly of a pyrene–peptide conjugate to form hydrogels. The peptide has been rationally designed to favor the formation of β-sheet 1D assemblies and metal coordination through the Glu side chains. We studied in detail the self-assembly process in the presence of H+, Li+, Na+, K+, Ca2+, Ni2+, Cu2+, Zn2+, Cd2+, Co2+, Fe3+, and Cr3+ and found that the morphology and mechanical properties of the hydrogels are ion-dependent. Moreover, thanks to the presence of the metal, new applications could be explored. Cu2+ metallogels could be used for amine sensing and meat freshness monitoring, while Zn2+ metallogels showed good selectivity for cationic dye adsorption and separation.