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The phenomena that results on supramolecular aggregations of bimetallic[Pt2L4] and [AuL2] are reviewed. Supramolecular [AuL2]n (n = 2,3) wereobserved in some cases in solution as a result of Au(I)···Au(I) aurophilicinteractions, which also direct the assembly of oligomeric structures in crys-tal phase. Analogously, Pt(II)···Pt(II) attraction accounts for the assembly of[Pt2L4]nsupramolecules which can result on 1D semiconductive arrangementsin crystal phase and direct the formation of 1D nanofibres on surfaces. Finally,oxidation of [Pt2L4] to [Pt2L4I]n produces highly conductive polymers thatcan reversibly assemble/disassemble into [Pt2L4] and [Pt2L4I2]. Such out-standing ability results on an unprecedented processability that enables MMXpolymers for technological applications as molecular wires.

It is a great challenge for the rational molecular design of light-emitting conjugated polymers to inherently suppress the ubiquitous coffee-ring effect (CRE), which is the critical bottleneck for ...

Chiral recognition of essential amino acids (EAAs) is a huge challenge that keeps plaguing analytical scientists due to their cryptochirality and limited steric interaction sites. Inspired by the superior enantioselectivity of functional supramolecular cyclodextrins (CDs) and strong signal amplification ability of field effect transistors (FETs), this work firstly reports a cationic supramolecular charge switch for facile enantiodiscrimination of EAAs based on extended-gate organic FET (EG-OFET). The cationic phenylcarbamoylated-CD single isomer acts as a charge switch via interacting with different enantiomers and the weak stereo-differentiation intermolecular interaction signals between the cationic perphenylcarbamoylated CDs and EAAs on the EG can be strongly and rapidly amplified through an OFET. Efficient chiral differentiation of six EAAs, including phenylalanine, tryptophan, leucine, isoleucine, lysine and valine, are successfully achieved without any derivation process and the detection limit for D-phenylalanine is down to 10−13 mol/L. We believe that this study provides a new and facile sensing perspective for natural amino acids and may afford deeper understanding of molecular chirality.

A linear supramolecular polymer with controllable features based on twisted cucurbit[14]uril (tQ[14]) and cucurbit[8]uril (Q[8]) was firstly fabricated via an effective self-sorting strategy. Herein we designed a monomer, 1-butyl-1′-(naphthalen- 2-ylmethyl)-4,4′-bipyridinium bromide (BNB), that contains bipyridyl, aliphatic butyl and aromatic naphthyl groups, simultaneously. Two host molecules, tQ[14] and Q[8] were employed to develop an effective strategy for constructing a linear supramolecular polymer with controllable features. The alkyl groups on both sides of BNB could insert into the two cavities of tQ[14], the naphthyl part of BNB via π-π stacking in Q[8] cavity, serving as the driving force for supramolecular polymerization. Through self-sorting of the monomer, tQ[14] and Q[8], led to the formation of the linear supramolecular polymer. Depolymerization could be achieved by addition of adamantane hydrochloride (AH) which driven two BNB guest molecules out of the Q[8] cavity. This self-sorting strategy has great potential, not only for designing supramolecular polymer materials with different controllable structures through introduction of multiple functional groups, but also for broadening the application of twisted cucurbit[14]uril in supramolecular chemistry.

Conformational regulation among two or more distant sites is not only one of the main pathways to accomplish multiple tasks in complex biological systems but also represents a powerful strategy to obtain stimuli-responsive supramolecular nanoconstructs with tailored physicochemical performance. We herein report the fabrication of a photochromic supramolecular assembly, which can be synergistically activated by the conformational regulation with bis(4,8-disulfonato-1,5-naphtho)-32-crown-8 and then reversibly switched by the through-space communication between restricted stilbazolium salt and photochromic dithienylethene. This work demonstrates that the synergistic conformational modulation via intra- and intermolecular interactions can be developed as a generalizable approach to construct more advanced biomimetic nanomaterials.

Detection of nucleoside derivatives has paramount importance because they are the essential biomolecular units for all life. Herein, we report a host-guest approach by using a fluorescent tetraphenylethene-based octacationic cage as host and 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS) as guest and fluorescent indicator to form non-fluorescent 1:1:1 host-(endo-exo)guest complex in water. This new host-(endo-exo)guest complex can be successfully used for detecting nucleosides (e.g., ATP and GTP), DNA (e.g., sm-DNA), and antibiotics (e.g., Penicillin G) with off-on fluorescence response via a competitive host-guest exchange with HPTS as exo-guest in water. Furthermore, this on-off-on fluorescent host-guest complex is also used for cell imaging based on ATP concentration in HeLa cells. Therefore, this study not only provides insight into the construction of a supramolecular probe with on-off-on fluorescence via host-guest complexation and exchange in solution, but also realizes a universal method for detecting and monitoring biomolecules.

The topology of polymers plays an essential role in their chemical, physical and biological properties. However, their effects on chirality-related functions remain unclear. Here, we reported the topology-controlled chirality expression in the chiral supramolecular system for the first time. Two topological supramolecular polymers, hyperbranched (HP) and linear (LP) supramolecular polymers produced by the host–guest interactions of branched and linear monomers, respectively, exhibited completely different chirality expressions despite the same molecular chirality of their monomers. Significantly, due to the branch points and strong steric hindrance existing in HP, cis-HP showed an enhanced and sign-inverted Cotton effect in the n–π* bands compared with cis-LP, as a result that the distinctive chirality induction and transfer were controlled by the topological skeletons. This topology-controlled chirality induction and transfer in the photoswitchable supramolecular polymers not only enables us to elucidate the in-depth effects of topology on the chiral expression in biopolymers but also inspires the design of chiroptical and bioinspired materials.

Novel aggregation-induced charge transfer (CT) emission systems with long luminescence lifetime directed by supramolecular strategy have been successfully developed in water. The dimethylacridine-based electron donor (BrAc) with excellent aggregation ability can co-aggregate with a triazine-based electron acceptor (TRZ) to form nanorods in water, which exhibit CT emission with long lifetime (τ = 0.92 μs). As for a similar electron donor (QaAc) with poor aggregation ability, water-soluble pillar[5]arene (WP5) can be introduced to promote the aggregation process, leading to the obvious CT emission with long lifetime (τ = 0.61 μs). In addition, structural modification of the acceptor with substituent groups possessing stronger electron-accepting capabilities will cause red-shift (about 50 nm) of the emission, which allows conveniently constructing long lifetime organic luminescent materials with different emission colors.

In recent years, polymeric materials with the ability to self-assemble into micelles have been increasingly investigated for application in various fields, mainly in biomedicine. Micellar morphology is important and interesting in the field of drug transport and delivery since micelles can encapsulate hydrophobic molecules in their nucleus, improve the solubility of drugs, have active molecules in their outer layer, and, due to their nanometric size, they can take advantage of the EPR effect, prolong circulation time and avoid renal clearance. Furthermore, bioactive molecules (could be joined covalently or by host-host interaction), such as drugs, bioimaging molecules, proteins, targeting ligands, “cross-linkable” molecules, or linkages sensitive to internal or external stimuli, can be incorporated into them. The confined multivalent cooperativity and the ability to modify the dendritic structure provide versatility to create and improve the amphiphiles used in the micellar supramolecular field. As discussed in this review, the most studied structures are hybrid copolymers, which are formed by the combination of linear polymers and dendrons. Amphiphilic dendrimer micelles have achieved efficient and promising results in both in vitro and in vivo tests, and this encourages research for their future application in nanotherapies.

As an important attempt towards creating hierarchical structures more like nature, the peptide is employed as a building block to build supramolecular architectures. An emerging question is whether the molecular mechanism of self-assembly obtained from the small molecule system, e.g., the driving forces of assembly are conventionally regarded as pairwise-additive, can be manifested in the self-association of biologically relevant amphiphilic peptides. A peptide, KRT-R, was derived from the 120-144 segment of keratin 14. The single cation-to-cation substitution with KRT-R at the site of 125 from arginine (R) to either lysine (K) or histidine (H) results in the peptide helices, KRT-K and KRT-H, sharing 96% sequence identity. These KRT-derived peptides possess similarities in the folding structures but exhibit divergent self-assembled structures. KRT-R and KRT-K self-assemble into sheets and fibrils, respectively. Whereas KRT-H associates into heterogeneous structures, including sheets, particles, and branched networks. The intrinsic tyrosine fluorescence spectroscopy measurements with the KRT-derived peptides within a temperature range of 25 °C to 95 °C reveal that the heating-triggered structural transitions of KRT-derived peptides are divergent. The alternation of single cationic residue changes the thermodynamic signature of peptide assemblies upon heating. A chemical denaturation experiment with KRT-derived peptides indicates that the intermolecular interactions that govern the supramolecular architectures formed by peptides are distinct. Overall, our work demonstrates the contribution of the interplay among various noncovalent interactions to supramolecular assembly.

Hypothesis Mixtures of colloids and supramolecular polymers may exhibit stimuli-responsive phase behaviour. However, in theoretical descriptions of such systems, the polymers are commonly described either as flexible chains or as rigid rods, while in experimental systems supramolecular polymers usually fall in between these two limits. We expect the flexibility of the polymers to have a profound effect on the stimuli-responsive phase behaviour. Theory We propose a general approach to predict the phase behaviour of colloidal hard spheres mixed with covalent or supramolecular polymers of arbitrary persistence length using free volume theory and an interpolation between flexible and rigid chains. Findings The binodals are predicted to shift to lower monomer concentrations as the persistence length is increased, making the polymers more efficient depletants. The persistence length is therefore an additional degree of freedom for manipulating the phase behaviour of colloid–polymer mixtures. We show that by manipulating the persistence length of temperature responsive supramolecular polymers, a wide range of phase diagrams with various topologies can be obtained. For example, we find phase diagrams with a critical point but no triple point or displaying two triple points for temperature-sensitive supramolecular polymers mixed with hard spheres.

Hypothesis: In the quest for large but well-controlled supramolecular structures, the discotic benzene-1,3,5-tricarboxamide (BTA) has received quite some attention, because it can form hydrogen-bonded stacks that can be regarded as supramolecular polymers of which the single BTA molecule is the monomer. In this report, we consider a more complex BTA-based supramolecular polymer, namely one that is built up from supramolecular ‘monomers’. Experiments: We design a tris-ligand L3 consisting of a BTA core carrying three dipicolinic acid (DPA) groups. L3 itself is too small to form polymers, but in the presence of appropriate metal ions, each L3 can form three coordination bonds and so form (L3)n clusters that are large enough to stack successfully: at an appropriate metal dose, long and stable filaments with a cross-sectional diameter of 12 nm appear. We monitor the growth process by UV–vis spectroscopy and light scattering, and use small angle X-ray scattering (SAXS), TEM as well as molecular simulation to confirm the filamentous structure of the fibers and determine their dimensions. Findings: The formation and structure of the fiber are very similar for various transition metal ions, which enables introducing different functionalities, e.g., magnetic relaxivity, by proper choice of the metal ions. Hence, we obtain a doubly supramolecular polymer, connected axially by hydrogen bonds, and radially by coordination bonds. Not only does this realize a higher level of complexity, but it also allows to easily introduce and vary metal-derived functionalities.

Summary Although advances in coating technologies have allowed us to match—or even exceed—the lubricity of Nature’s low-friction surfaces, the performance of synthetic materials inevitably diminishes over time as the surfaces are worn and damaged by irreversible breakage of covalent bonds. Synthetic systems lack the bespoke repair mechanisms that replenish hydration lubrication surfaces in Nature. Here, we demonstrate dynamic repair of low-friction surfaces prepared through a surface-selective self-assembly strategy. Monolayers of lubricating polymers associate with functionalized surfaces through strong and specific host–guest interactions, leading to hydration lubrication surfaces with low coefficients of friction (0.024–0.028). Following friction-induced dissociation of the polymers, the polymer-to-surface interaction is restored by the reformation of host–guest complexes, thus repairing the monolayer, renewing the lubricity, and reducing the effects of wear. Such dynamically restored low-friction materials will be an essential tool in decreasing global energy use—a fifth of which is expended overcoming friction.

Purely organic room-temperature phosphorescence (RTP) has attracted tremendous attention, but is rarely reported to possess stimulus responsiveness. Herein, we report a supramolecular RTP switch based on a dicationic guest molecule (BPA) and cucurbituril. BPA possesses a photosensitive 9,10-diphenylanthracene core and terminal 4-(4-bromophenyl)pyridium, which can form 1 : 4 supramolecular assembly with cucurbit[7]uril (CB[7]) and an n : n linear supramolecular polymer with cucurbit[8]uril (CB[8]). The assemblies can exhibit tunable fluorescence emission after undergoing a photoreaction of the anthracene unit in BPA. It is interesting that CB[8] can bind two bromophenylpyridinium units to form a green phosphorescent switch. Notably, the RTP of the assemblies can be reversibly switched on/off by UV irradiation or heating through a tunable Forster resonance energy transfer from 4-(4-bromophenyl)pyridium to anthracene. Moreover, the addition of cucurbituril can significantly accelerate the photoreaction rate of anthracene and enable the assembly to respond quickly to UV irradiation, which expands the application potential of this strategy in stimulus responsive RTP materials.

Pagoda[5]arene (P5), which is composed of five 2,6-dimethoxylanthracene (2,6-DMA) subunits bridged by methylene groups at 1,5 positions, was conveniently synthesized in 43% by trifluoroacetic acid ...

In this work we report on new heteroleptic coordination compounds [Pb2(LI)2](NO3)2∙2MeOH (1), [Pb2(LII)2](NO3)2 (2), [Pb2(LIII)2](NO3)2∙MeOH∙H2O (3) and [Pb2(LIII)2(H2O)](NCS)2 (4), which were obtained through self-assembling of 2-(amino(pyridin-2-yl)methylene)hydrazine-1-carbothioamide (HLI), 2-(amino(pyrazin-2-yl)methylene)hydrazine-1-carbothioamide (HLII) or 2-(amino(pyridin-2-yl)methylene)-N-methylhydrazine-1-carbothioamide (HLIII) with Pb(NO3)2 or a mixture of Pb(ClO4)2 and KNCS, respectively. In all the obtained complexes the lead(II) cation is N,N',S-chelated by the tridentate pincer type monodeprotonated ligand LI–III. In addition to the thiosemicarbazone chelation, the sulfur atom in each structure acts as bridging to connect two [Pb(LI–III)]+ units to form a dinuclear dimeric species having a centrosymmetric geometry, so that the ligands are directed either at different, in 1 and 2, or the same, in 3 and 4, side of the coplanar Pb2S2 core. In the latter structures two metal centers are additionally linked with each other through the oxygen atom of the bridging water molecule. The dimeric units in 1–4 are further linked through the Pb–N tetrel bonds, yielding 1D supramolecular polymeric chains, which, in turn, are interlinked though a myriad of other intermolecular noncovalent inetaractions, including tetrel bonds, hydrogen bonds and π-stacking. Counterions (NO3– and NCS–) as well as co-crystallized solvent molecules (MeOH and H2O) are also responsible in further stabilization of the overall crystal packing of the obtained complexes as a source of either tetrel and/or hydrogen bonds. The observation of the recurrent tetrel bonds in compounds 1–4 has been rationalized using DFT calculations and molecular electrostatic potential (MEP) surface plots. Moreover, coordination bonds (covalent character) and tetrel bonds (noncovalent character) between the complexes and their conterions (and water moelcule) have been differentiated using the quantum theory of «atoms-in-molecules» (QTAIM) and the noncovalent interaction index (NCI index) computational methods.

The pollution and damage caused by antibiotics in water have aroused serious concern. Metal–organic frameworks (MOF), which have been hotly investigated as a novel kind of sensing materials, have been tentatively applied to the detection of antibiotics in recent years. In this work, four new Zn(II)/Cd(II) coordination polymers, [Cd(opda)(mbib)(H2O)] (1), [Cd(opda)(pbib)(H2O)] (2), [Cd(ppda)(mbib)] (3), and [Zn2(mpda)2(mbib)2]·2H2O (4), (H2opda = 1,2-phenylenediacetic acid, H2mpda = 1,3-phenylenediacetic acid, H2ppda = 1,4-phenylenediacetic acid, mbib = 1,3-bis(imidazolyl)benzene, pbib = 1,4-bis(imidazolyl)benzene), have been synthesized using bis(imidazole) and phenylenediacetate isomers under hydrothermal conditions. The flexible pda and bib ligands in 1–3 afford 2D (4,4)-connected layers, which are further stacked in an offset fashion with an ABAB sequence to propagate into a 3D supramolecular architecture through strong C–H⋯π and C–H⋯O interactions. In contrast, the flexible cis-conformation mpda and mbib ligands in 4 can be seen as “V”-type building blocks, linking Zn(II) atoms to form a 1D loop chain. The structural diversity of these complexes is mainly attributed to the different coordination modes and isomer conformations of the flexible phenylenediacetic acid and bis(imidazole) ligands. The application of the fluorescence properties of the four complexes for detecting the antibiotics cefixime (CEF) and tetracycline (TEC) and the related mechanisms have been researched. Complexes 1–4 exhibit high quenching percentages in low-concentration aqueous solutions, with values of 94.9%, 97.8%, 95.5%, and 97.2% (toward CEF) and 97.7%, 96.7%, 96.4%, and 97.4% (toward TEC), respectively. Compared with 1–3, complex 4 has a higher quenching percentage, which may be because 4 is a 3D porous supramolecular network. The detection limits of complexes 1–4 have been measured to be 0.278 μM, 0.379 μM, 0.52 μM, and 0.171 μM (for CEF) and 0.384 μM, 0.189 μM, 0.421 μM, and 0.137 μM (for TEC), which surpass/approach those of most of the reported MOF-based fluorescent sensing materials. Systematic analysis of the sensing mechanism reveals that photoinduced electron transfer and the inner filter effect contribute to the realization of the sensing process.

Over the past few decades, supramolecular chemistry has entered the field of scientific research and attracted extensive attention. Among supramolecular macrocycles, cyclodextrins (CDs) are widely applied in the field of adsorption due to their unique structure and properties. This review focuses on the important role of cyclodextrin polymers (CDPs) as adsorbents in the adsorption of different substances. It covers the category of CDPs adsorbents (including crosslinked CDPs, grafted CDPs, CD-based polyrotaxanes/pseudo-polyrotaxanes, and imprinted CDPs), their adsorption mechanism and applications in the adsorption of inorganic metal ions, organic pollutants, and biomacromolecules. Finally, the challenges and future perspectives in relative research fields are discussed.

International audience; Out-of-plane deformations of metalloporphyrin skeletons have been well documented as playing important roles in relevant biological processes. In contrast, out-of-plane binding to the N-core of large metal cations as period 6 post-transition elements has remained poorly investigated. We describe herein monometallic complexes of Pb(II) and Bi(III) with 5,10 single strapped porphyrin ligands bearing a carboxylic acid group with two possible “in/out” orientations, in which the metal ions are bound to the N-core of the macrocycle either from the strap side or from the naked side. In the case of Pb(II), both the kinetics of insertion and resulting OOP stereoselectivity are influenced by the “in/out” stereoisomerism of the overhanging COOH. Remarkably, Bi(III) insertion proceeded quasi-instantaneously at RT owing to the transmetalation of its Pb(II) counterpart. The addition of a cyano group in position of the carboxylic acid group generates a ligand exhibiting an increased stereoselectivity in the metalation processes with Pb(II) and Bi(III): these cations are coordinated exclusively from the naked and strap side of the macrocycle, respectively. This difference in behavior is likely explained by steric hindrance for the divalent cation, which is counterbalanced by the establishment of the second sphere of coordination with the strap for the trivalent cation. Such a behavior is thought of interest for the further design of adaptable supramolecular coordination assemblies.

11 p.-7 fig.-1 tab.1 graph. abst., Dynamic binding events are key to arrive at functionality in nature, and these events are often governed by electrostatic or hydrophobic interactions. Synthetic supramolecular polymers are promising candidates to obtain biomaterials that mimic this dynamicity. Here, we created four new functional monomers based on the benzene-1,3,5-tricarboxamide (BTA) motif. Choline or atropine groups were introduced to obtain functional monomers capable of competing with the cell wall of Streptococcus pneumoniae for binding of essential choline-binding proteins (CBPs). Atropine-functionalized monomers BTA-Atr and BTA-Atr3 were too hydrophobic to form homogeneous assemblies, while choline-functionalized monomers BTA-Chol and BTA-Chol3 were unable to form fibers due to charge repulsion. However, copolymerization of BTA-Chol3 with non-functionalized BTA-(OH)3 yielded dynamic fibers, similar to BTA-(OH)3. These copolymers showed an increased affinity toward CBPs compared to free choline due to multivalent effects. BTA-based supramolecular copolymers are therefore a versatile platform to design bioactive and dynamic supramolecular polymers with novel biotechnological properties., The authors acknowledge the financial support from the Dutch Ministry of Education, Culture and Science (Gravity program 024.001.035), the ERC Advanced Grant (SYNMAT─788618), the Gravitation Program “Materials Driven Regeneration”, funded by the Netherlands Organization for Scientific Research (024.003.013), and the Agencia Estatal de Investigacion AEI/FEDER-EU-10.13039/501100011033- and Ministerio de Ciencia e Innovación, Spain (PID2019-105126RB-I00)

Anti-Aβ therapy has dominated clinical trials for the prevention and treatment of Alzheimer's disease (AD). However, suppressing Aβ aggregation and disintegrating mature fibrils simultaneously remains a great challenge. In this work, we developed a new strategy using a charged tubular supramolecule (CTS) with pillar[5]arene as the backbone and modifying amino and carboxyl groups at the tubular terminals (noted as CTS-A, CTS-A/C, and CTS-C, respectively) to suppress Aβ fibrillation for the first time. According to the spectroscopic and microscopic characterizations, Aβ40 fibrillation can be efficiently suppressed by CTS-A in a very low inhibitor:peptide (I:P) molar ratio (1:10). A greatly alleviated cytotoxic effect of Aβ peptides after the inhibition or disaggregation process is further disclosed. The well-organized supramolecular structure drives multivalent interaction and gains enhanced efficiency on amyloid fibrillar modulation. These results open a new path for the design of supramolecules in the application of AD treatment.

A number of artificial cation ionophores (or transporters) have been developed for basic research and biomedical applications. However, their mechanisms of action and the putative correlations between changes in intracellular cation concentrations and induced cell death remain poorly understood. Here we show that three hemispherand-strapped calix[4]pyrrole based ion pair receptors act as efficient Na+/K+ exchangers in the presence of Cl- in liposomal models, and promote Na+ influx and K+ efflux (Na+/K+ exchange) in cancer cells to induce apoptosis. Mechanistic studies reveal that these cation exchangers induce endoplasmic reticulum (ER) stress in cancer cells by perturbing intracellular cation homeostasis, promote generation of reactive oxygen species, and eventually enhance mitochondria-mediated apoptosis. However, they neither induce osmotic stress nor affect autophagy. The present study provides support for the notion that synthetic receptors which perturb cellular cation homeostasis may provide a new approach to generating agents with potentially useful apoptotic activity.

Herein, nanocomposites films were prepared via the facile casting method by incorporating cellulose nanocrystals (CNCs) with arabinogalactan (AG), galactomannan (GM) or konjac glucomannan (KGM) respectively. The introduced polysaccharides maintained the transparency of CNCs films and promoted the UV blocking properties. In addition, mechanical strength of the nanocomposite films was greatly improved after the combination of polysaccharides. The interactions of hydroxyl-abundant macromolecules, smoother and tighter morphological structures, as well as the disturbed crystal structure were proved to be responsible for the improved properties. Hydrophilic lattice planes of cellulose crystallites were determined to interact with polysaccharides resulting in lower crystallite sizes and crystallinity. The cell culture assay revealed that the films had no cytotoxicity and presented a satisfactory cytocompatibility, because of the polysaccharides from plant cell walls introduced into the films. Therefore, the biocompatible nanocomposites films can be tuned by the addition of polysaccharides, which show great potentials for materials modification in optical, packaging and biomedical fields.

A sandwich-like melamine/phytic acid/silicon nitride hybrid (SW-Si3N4) sheets were prepared by supramolecular wrapping as the hybrid flame retardants for thermoplastic polyurethane (TPU). The introduction of Si3N4 sheets as a template could not only induce the generation of two-dimensional phytic/melamine (PAMA) capping layers, but also produce the synergistic flame-retardant effect on TPU composites. Cone test showed that heat release rate (HRR), smoke production rate (SPR) and total smoke production (TSP) values of TPU were decreased obviously by adding SW-Si3N4. TG-IR test indicated the dramatic inhibition of aromatic compound, hydrocarbons, CO and HCN release. Besides, the thermal conductivity of composites was obviously improved by adding SW-Si3N4. This work may provide better reference for developing multi-functional TPU composites for diverse application.

Small-molecular targeting peptides possess features of biocompatibility, affinity, and specificity, which is widely applied in molecular recognition and detection. Moreover, peptides can be developed into highly ordered supramolecular assemblies with boosting binding affinities, diverse functions, and enhanced stabilities suitable for biosensors construction. In this Review, we summarize recent progress of peptide-based biosensors for precise detection, especially on tumor-related analysis, as well as further provide a brief overview of the progress in tumor immune-related detection. Also, we are looking forward to the prospective future of peptide-based biosensors.

Homoleptic pyridyl-3(N) functionalized dithiocarbamate complexes namely, [Zn(L1)2]2 1 (L1 = (C5H4NCH2)2NCS2) and [Cd(L2)2] ∞ 2 (L2 = CH3C6H4CH2NCS2CH2C4H3O) have been synthesized and characterized by elemental analysis and different spectroscopic techniques. Single crystal structural studies reveal that compound 1 is binuclear while, 2 is polymeric structure. The presence of weak interactions between complexes and solvent molecules in the lattice results in one-dimensional and three-dimensional supramolecular structures of 1 and 2 respectively. In the case of complex 2, a rare and significant S···Cl chalcogen bonding interaction was found, which involve the solvent molecule in chain motifs. Complex 2 is a unique example of homoleptic metal dithiocarbamate complexes exhibiting such types of interactions. Complexes showed emission in the solid state. The TGA studies of complexes revealed that complex 1 would be a good precursor for the preparation of ZnS thin film via metal organic chemical vapor deposition (MOCVD).

We present the design, synthesis, and characterization of triple hydrogen-bond-forming precursors and their supramolecular triblock copolymers. Thymine end-functionalized polystyrene-b-polyisoprene...

The controlled release of guest molecules from cyclodextrin (CD) inclusion complexes is very important for specific industrial applications in foods, medicine, cosmetics, textiles, agriculture, environmental protection, and chemical materials. The term "controlled release" encompasses several related methods, including those referred to as immediate release, sustained release and targeted release. Many different CD-based controlled release systems are currently used in practical applications. CD inclusion complexes, CD coupling, supramolecular hydrogels, and supramolecular micelles are among the most common. This review systematically introduces the principles and applications of CD-based controlled release systems, providing a theoretical basis for improving the bioavailability of effective substances and broadening their range of application.

Chiral amphiphiles are useful for controlling the structures and properties of supramolecular assemblies, but their stereocontrolled synthesis is generally difficult, because their long alkyl chains tend to bring unfavorable effects on the solubility, reactivity, and crystallinity of molecules. Typical examples are amphiphilic 1,2-amino alcohols (S)-1 and (1S,2S)-2 developed by our group, which were known to serve as chiral reaction media for controlling the stereochemistry of asymmetric photoreactions. We previously developed synthetic schemes for these 1,2-amino alcohols, but their synthetic efficiencies were unsatisfactory (13 steps with 2% overall yield for (S)-1; eight steps with 8% yield for (1S,2S)-2). As the main reason of such low efficiencies, the stereocontrolling methods we previously employed (diastereomer-salt crystallization for (S)-1; stereoselective reactions for (1S,2S)-2) were not ideal. Here, we report highly improved synthetic schemes for (S)-1 and (1S,2S)-2 based on the enantioselective high performance liquid chromatography (HPLC) separation of intermediates in preparative scales. Compared with the previous schemes, the new schemes are advantageous in fewer number of steps, higher overall yield, and lower risk of racemization (seven steps with 15% overall yield for (S)-1; seven steps with 26% overall yield for (1S,2S)-2).

Supramolecular antimicrobial materials based on synthetic macrocycles have recently aroused enormous interests due to their controllable and effective antibacterial treatment. Herein, a multicharged supramolecular assembly was fabricated employing the moderate host-guest interaction between hexa-adamantane-appended ruthenium polypyridyl (Ru2) and polycationic cyclodextrin (CD-QAS) in water. The positively multicharged feature of supramolecular assembly could remarkably enhance the specific intercalation and accumulation in negatively charged bacteria membrane leading to the physical membrane damage. Subsequently, the assembly could efficiently initiate the significant generation of singlet oxygen (

Nucleobase mimicking small molecules able to reconfigure DNA are a recently discovered strategy that promises to extend the structural and functional diversity of nucleic acids. However, only simple, unfunctionalized molecules such as cyanuric acid and melamine have so far been used in this approach. In this work, we show that the addition of substituted cyanuric acid molecules can successfully program polyadenine strands to assemble into supramolecular fibers. Unlike conventional DNA nanostructure functionalization, which typically end-labels DNA strands, our approach incorporates functional groups into DNA with high density using small molecules and results in new DNA triple helices coated with alkylamine or alcohol units that grow into micrometer-long fibers. We find that small changes in the small molecule functional group can result in large structural and energetic variation in the overall assembly. A combination of circular dichroism, atomic force microscopy, molecular dynamics simulations, and a new thermodynamic method, transient equilibrium mapping, elucidated the molecular factors behind these large changes. In particular, we identify substantial DNA sugar and phosphate group deformations to accommodate a hydrogen bond between the phosphate and the small-molecule functional groups, as well as a critical chain length of the functional group which switches this interaction from intra- to interfiber. These parameters allow the controlled formation of hierarchical, hybrid DNA assemblies simply through the addition and variation of small, functionalized molecules.

A new 2D coordination polymer, namely{[Cd2(BDC)2(bmb)2]·H2O}n (1) (H2BDC = 1,4-benzenedicarboxylic acid and bmb = 1,4-bis(2-methyl-1H-imidazol-1-yl)butane), has been prepared and full characterized. Coordination polymer 1 has 2D layer, which was further extended into 3D supramolecular motif through the π–π packing interactions. Coordination polymer 1 illustrated effectively photocatalytic performance to the disintegration of dyes Rhodamine B (Rh B), methyl orange (MO) and methylene blue (MB). Coordination polymer 1 can remove the dye MB with 90.37% after 100 min under simulated UV light and its catalytic feature conforms to the first order kinetics model. In addition, the possible mechanism of the catalytic degradation toward MB was suggested through the trapping experiments and LC–MS methods.

Fibril motion improves peptide signaling Artificial scaffolds that bear the peptide-signaling sequences of proteins for tissue regeneration often have limited effectiveness. Álvarez et al . synthesized supramolecular peptide fibril scaffolds bearing two peptide sequences that promote nerve regeneration, one that reduces glial scarring and another that promotes blood vessel formation (see the Perspective by Wojciechowski and Stevens). In a mouse model of paralyzing human spinal cord injury, mutations in a tetrapeptide domain outside of the signaling regions improved recovery by promoting intense supramolecular motion within the fibrils. The mutation with the most intense dynamics resulted in corticospinal axon regrowth and myelination, functional revascularization, and motor neuron survival. —PDS

The research in circularly polarized luminescence has attracted wide interest in recent years. Efforts on one side are directed toward the development of chiral materials with both high luminescence efficiency and dissymmetry factors, and on the other side, are focused on the exploitations of these materials in optoelectronic applications. This review summarizes the recent frontiers (mostly within five years) in the research in circularly polarized luminescence, including the development of chiral emissive materials based on organic small molecules, compounds with aggregation-induced emissions, supramolecular assemblies, liquid crystals and liquids, polymers, metal-ligand coordination complexes and assemblies, metal clusters, inorganic nanomaterials, and photon upconversion systems. In addition, recent applications of related materials in organic light-emitting devices, circularly polarized light detectors, and organic lasers and displays are also discussed.

Supramolecular adhesives that enable debonding on-demand are of significant research interest for the development of adaptive and smart materials, yet, biodegrable supramolecular adhesives have been rarely exploited. Herein, telechelic, three-armed and four-armed CO2-based polyols with close molecular weights and various CO2 content (or carbonate unite content) have been synthesized via a zinc-cobalt double metal cyanide complex catalyzed ring-opening copolymerization of CO2 and propylene oxide, and further exploited as sustainable and biodegradable building blocks for supramolecular polymers (SMPs) with 2-ureido-4[1H]-pyrimidinone (UPy) motifs. Notably, the orthogonal modulation of the CO2 content and the topology of CO2-based polyols provide a unique opportunity to fine-tune the surface energy as well as the cohesive strength of the resulting CO2-based SMPs. Notably, a three-armed SMP with 44% CO2 (3UPy-CO2-44%) can well balance the trade-off between surface energy and cohesive strength, therefore bestowing a high adhesive strength of 7.5 and 9.7 MPa towards stainless steel and wood substrates respectively by testing the corresponding single lap joints. Moreover, the light-responsive adhesion property of 3UPy-CO2-44% has been demonstrated exemplarily by blending with a UV sensitizer.

Hierarchic self-assembly underpins much of the form and function seen in synthetic or biological soft materials. Lipids are paramount examples, building themselves in nature or synthetically in a variety of meso/nanostructures. Synthetic block copolymers capture many of lipid's structural and functional properties. Lipids are typically biocompatible and high molecular weight polymers are mechanically robust and chemically versatile. The development of new materials for applications like controlled drug/gene/protein delivery, biosensors, and artificial cells often requires the combination of lipids and polymers. The emergent composite material, a "polymer-lipid hybrid membrane", displays synergistic properties not seen in pure components. Specific examples include the observation that hybrid membranes undergo lateral phase separation that can correlate in registry across multiple layers into a three-dimensional phase-separated system with enhanced permeability of encapsulated drugs. It is timely to underpin these emergent properties in several categories of hybrid systems ranging from colloidal suspensions to supported hybrid films. In this review, we discuss the form and function of a vast number of polymer-lipid hybrid systems published to date. We rationalize the results to raise new fundamental understanding of hybrid self-assembling soft materials as well as to enable the design of new supramolecular systems and applications.

Accurate control of the layer number of orderly stacked 2D polymers has been an unsettled challenge in self-assembly. Herein we describe the fabrication of a bilayer 2D supramolecular organic framework from a monolayer 2D supramolecular organic framework in water by utilizing the cooperative coordination of a rod-like bipyridine ligands to zinc porphyrin subunits of the monolayer network. The monolayer supramolecular framework is prepared from the co-assembly of an octacationic zinc porphyrin monomer and cucurbit[8]uril (CB[8]) in water through CB[8]-encapsulation-promoted dimerization of 4-phenylpyridiunium subunits that the zinc porphyrin monomer bear. The bilayer 2D supramolecular organic framework exhibits structural regularity in both solution and the solid state, which is characterized by synchrotron small-angle X-ray scattering and high-resolution transmission electron microscopic techniques. Atomic force microscopic imaging confirms that the bilayer character of the 2D supramolecular organic framework can be realized selectively on the micrometer scale.

Cholesterol crystals (CCs), originally accumulating in the lysosome of cholesterol-laden cells, can aggravate the progression of atherosclerosis. β-cyclodextrin (CD) is a potent cholesterol acceptor or CC solubilizer. However, the random extraction of cholesterol impedes the in vivo application of CD for removing lysosomal CCs. Here, we exploit poly-β-cyclodextrin (pCD) as a lysosomal CC solubilizer and dextran sulfate grafted with benzimidazole (BM) as a pH-sensitive switch (pBM) to self-assemble into a supramolecular nanoassembly (pCD/pBM-SNA). The CD cavity in pCD/pBM-SNA can be efficiently sealed by hydrophobic BM at pH 7.4 (OFF). After it enters the lysosome, pCD/pBM-SNA disassembles, recovers the CD cavity to dissolve CCs into free cholesterol due to the protonation of BM (ON), and reduces CCs, finally enhancing the cholesterol efflux and promoting atherosclerosis regression. Our findings provide an "OFF-ON" tactic to remove lysosomal CCs for antiatherosclerosis as well as other diseases such as Niemann-Pick type C diseases with excessive cholesterol accumulation in the lysosome.

Polymer nanocapsules have demonstrated significant value in materials science and biomedical technology, but require complicated and time-consuming synthetic steps. We report here the facile synthesis of monodisperse polymer nanocapsules via a redox-mediated kinetic strategy from two simple molecules: dopamine and benzene-1,4-dithiol (BDT). Specifically, BDT forms core templates and modulates the oxidation kinetics of dopamine into polydopamine (PDA) shells. These uniform nanoparticles can be tuned between ≈70 and 200 nm because the core diameter directly depends on BDT while the shell thickness depends on dopamine. The supramolecular core can then rapidly disassemble in organic solvents to produce PDA nanocapsules. Such nanocapsules exhibit enhanced physicochemical performance (e.g., loading capacity, photothermal transduction, and anti-oxidation) versus their solid counterparts. Particularly, this method enables a straightforward encapsulation of functional nanoparticles providing opportunities for designing complex nanostructures such as yolk-shell nanoparticles.

This article describes a generally applicable supramolecular design for construction of ultrathin two-dimensional (2D) nanosheets with a functionalized surface, by aqueous self-assembly of core-sub...

An amphiphilic phosphodiester-linked azobenzene trimer has been exploited in the development of stimuli-responsive water-soluble supramolecular polymers. It can reversibly undergo thermal and photoisomerization between Z and E isomers in EtOH solution. Its self-assembly properties in aqueous medium have been investigated by spectroscopic and microscopic techniques, demonstrating that E - and Z -azobenzene trimers form supramolecular nanosheets and toroidal nanostructures, respectively. By virtue of the E /Z photoisomerization of azobenzene units of the trimer, these two different supramolecular morphologies can be switched upon photoirradiation. This finding paves the way towards stimuli-responsive water-soluble supramolecular polymers which hold great promise in the construction of smart functional materials and also in biological applications.

Supramolecular organic frameworks (SOFs), due to the atomically precise integration of the repeated building units, exhibit intriguing properties and consequently potential applications in chemical...

Sulfonic acid groups with C3ν symmetry can coordinate with metal ions to produce multidimensional structures due to their flexible coordination modes. They can also penetrate into supramolecular structures through an intriguing bridging pattern and weak interactions. Herein, a novel heterocyclic sodium sulfonate supramolecular structure, namely [Na(Pyr-SO3)(H2O)]n where Pyr-SO3H is pyrazine sulfonic acid, is synthesized by utilizing NaBF4 to coordinate with the P–SO3H ligand through the solvent evaporation method. The single crystal X-ray diffraction (XRD) data indicate that the as-formed structure belongs to the Pbca space group. Additional properties are characterized by powder XRD, thermal analysis, and solid-state fluorescence. In particular, the introduction of a soft alkali metal ion can coordinate with the oxygen atom of the sulfonate ligand and form a Na–O bridging configuration that can not only significantly improve the pyrazine sulfonic acid ligand coordination ability, but also provide a reference for the extended study of functional sulfonate polymers in the future. Electronic supplementary material Supplementary material is available for this article at 10.1134/S0022476621110172 and is accessible for authorized users.

Multivalent supramolecular assemblies have recently attracted extensive attention in the applications of soft materials and cell imaging. Here, we report a novel multivalent supramolecular assembly constructed from 4-(4-bromophenyl)pyridine-1-ium bromide modified hyaluronic acid (HABr), cucurbit[8]uril (CB[8]) and laponite® clay (LP), which could emit purely organic room-temperature phosphorescence (RTP) with a phosphorescence lifetime of up to 4.79 ms in aqueous solution via multivalent supramolecular interactions. By doping the organic dyes rhodamine B (RhB) or sulfonated rhodamine 101 (SR101) into the HABr/CB[8]/LP assembly, phosphorescence energy transfer was realized with high transfer efficiency (energy transfer efficiency = 73–80%) and ultrahigh antenna effect (antenna effect value = 308–362) within the phosphorescent light harvesting system. Moreover, owing to the dynamic nature of the noncovalent interactions, a wide-range spectrum of phosphorescence energy transfer outputs could be obtained not only in water but also on filter paper and a glass plate by adjusting the donor–acceptor ratio and, importantly, white-light emission was obtained, which could be used in the application of information encryption., An ultralong lifetime supramolecular assembly was constructed via multivalent supramolecular interactions and achieved phosphorescence light harvesting. Multicolor (including white) broad-spectrum outputs could be achieved in water and also on filter paper and a glass plate.

Zwitterionic polymer materials have been extensively studied, but zwitterionic peptides supramolecular hydrogel materials are rarely studied. In this study, the preparation of two zwitterionic hydrogels using self-assembled peptides were reported. The hydrogels could be fabricated easily by changing the temperature or enzyme catalysis in a short time. And the differences in structure and function of the zwitterion peptide hydrogels caused by the two preparation methods were also be compared. We found that the hydrogel prepared by enzyme induced self-assembly has better solubility and lower cytotoxicity than that prepared by the heating-cooling process. The result showed the enzyme induced self-assembly way to form zwitterionic peptides supramolecular hydrogel materials could have further biomedical applications.

A new series of metal Complexes were prepared by refluxing nickel chloride with hot methanolic solution mixture of 8-Hydroxyquinoline and Schiff bases(L1-L6). Schiff base ligands were synthesised by the condensation of 4-aminopheno, 4-aminosalicylic acid, 2-aminobenzthiazole with salicylaldehyde and vanillin. The metal complexes have been characterised by gravimetric metal analysis, magnetic moment,conductivity measurement, 1HNMR and IR analysis.

Recently, heterocyclic compounds play important role in drug industries. The benzothiazole (BTA) is a bicyclic compound in heterocyclic because of their biological properties. In this paper the synthesis and characterization of benzothiazole were reported. The chemical structures of synthesized compounds were established based on spectral data of 1HNMR, 13CNMR, and IR. The mass of the novel compounds was established with the help of the LCMS test. The formation of the crystal was confirmed by powder XRD and the sharp peaks show the purity and crystalline nature of the samples. The photoluminescence spectra explain the optical property of the compound. The biological studies of synthesized compounds show that compound 5c possesses good antibacterial activity and compound 5d has good antifungal activity.

Metallo-hydrazones having the formula [M(IBAH)2] (where, M = Ni(II), Cu(II) and Zn(II); IBAH = p-Isopropylbenzaldehyde acetoylhydrazone) are prepared and confirmed on the basis of physico-chemical and spectral analyses. Conductivity data revealed that the complexes are non-electrolytes. Metal-DNA interactions are investigated using absorption spectrophotometry. Binding constant (Kb) data revealed that the copper complex interact DNA more strongly than other complexes. Antibacterial activity studies indicated higher activity for complexes than the metal free hydrazone ligand. The copper compound displays higher activity. DNA binding constants are correlated with the activity of metal compounds in this article.

MoCl5 reactions with 4-methylpyridine/2-methylpyridine/1-methylimidazole in THF in 1:1/1:2 stoichiometric ratios, at room temperature were carried out. The following products were synthesized: MoO2Cl(C6H7N), 1;Mo2O2Cl5(C6H7N)2(C4H8O)2,2; Mo4O4Cl4(C6H7N)3(C4H8O)2, 3 and Mo2O4Cl4(C4H6N)2(C4H8O), 4. These compounds have been investigated by FT-IR (transmission mode), FT-1H NMR, FT -13C NMR, microbiological, LC-MS and elemental (C, H, N, Mo, Cl) studies. In view of the sensitivity of all the reactants and products towards oxidation/hydrolysis by air/moisture, all the reactions and products were handled using dry nitrogen atmosphere in vacuum line. LC-MS and elemental studies agree with the formulae of compounds.