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Nanozymes, defined as nanomaterials with intrinsic enzymatic properties, have evoked fundamental new science and offer new paradigm technologies for developing multifunctional diagnostic and therapeutic nanoplatforms. To comprehend the field of nanozymes, this Editorial briefly reviews the significant developments in their design and fabrication, highlighting existing challenges and future perspectives, promoting the further flourishing development of nanozyme-based materials toward superior biomedical applications.

Abstract Avoiding the tedious process of crystal cultivation and directly obtaining organic crystals with desirable phosphorescent performance is of great significance for studying their structure and properties. Herein, a set of benzophenone‐cored phosphors with bright green afterglow are obtained on a large scale through in‐situ generation via an end‐capping strategy to suppress non‐radiative triplet excitons and reinforce the intermolecular interactions. The ordered arrangement of phosphors with alkyl‐cyano groups as regulators is crucial for the enhancement of room‐temperature phosphorescence (RTP) emission, which has been further verified by the attenuated lifetimes in isolated states through the formation of inclusion complexes upon binding with pillar[5]arenes. Moreover, the hierarchical interactions of phosphors, including hydrogen bonding, π‐π stacking interactions, and van der Waals forces, are quantified by crystal structures and theoretical calculation to deeply interpret the origins of RTP emission. With this study, we provide a potential strategy for the direct acquisition of crystalline organic phosphors and modulation of RTP.

Abstract In the treatment of refractory corneal ulcers caused by Pseudomonas aeruginosa, antibacterial drugs delivery faces the drawbacks of low permeability and short ocular surface retention time. Hence, novel positively‐charged modular nanoparticles (NPs) are developed to load tobramycin (TOB) through a one‐step self‐assembly method based on metal‐phenolic network and Schiff base reaction using 3,4,5‐trihydroxybenzaldehyde (THBA), ε‐poly‐ʟ‐lysine (EPL), and Cu2+ as matrix components. In vitro antibacterial test demonstrates that THBA‐Cu‐TOB NPs exhibit efficient instantaneous sterilization owing to the rapid pH responsiveness to bacterial infections. Notably, only 2.6 µg mL−1 TOP is needed to eradicate P. aeruginosa biofilm in the nano‐formed THBA‐Cu‐TOB owing to the greatly enhanced penetration, which is only 1.6% the concentration of free TOB (160 µg mL−1). In animal experiments, THBA‐Cu‐TOB NPs show significant advantages in ocular surface retention, corneal permeability, rapid sterilization, and inflammation elimination. Based on molecular biology analysis, the toll‐like receptor 4 and nuclear factor kappa B signaling pathways are greatly downregulated as well as the reduction of inflammatory cytokines secretions. Such a simple and modular strategy in constructing nano‐drug delivery platform offers a new idea for toxicity reduction, physiological barrier penetration, and intelligent drug delivery.

The development of responsive and smart drug nanocarriers that defeat the tumor microenvironment that resists cancer therapy has attracted considerable attention in recent decades. Upgrades are sought to effectively increase the therapeutic efficacy of chemotherapy drugs and reduce damage to normal tissues. In this study, a new type of silica nano-particle carrier, dual-functionalized mesoporous silica nanobeans (DF-MSNB), is used to encapsulate the drug, doxorubicin (DOX), to form the DOX@DF-MSNB complex. The complex simultaneously releases drugs and tracks drug uptake by cells after the environmentally triggered release of the encapsulated drug and fluorophore. Upon sensing the high GSH level and low pH in the tumor microenvironment, the disulfide bond breaks in the linker between the drug and the carrier. An attached fluorescent group is activated, and the DOX drug is released from the carrier. Our results show that DOX@DF-MSNB co-localizes with mitochondria and lysosomes in A2780 cells, enabling DOX to subvert the cells’ mitochondrial function and activate macrophage and mitochondrial autophagy. The application of a mitochondrial autophagy inhibitor confirms that DOX@DF-MSNB inhibits tumor development by activating mitochondrial autophagy.

Abstract Synthetic macrocycles have proved to be of great application value in functional charge-transfer systems in the solid state in recent years. Here we show a switchable on-off type vapochromic system toward 1-/2-bromoalkane isomers by constructing solid-state charge-transfer complexes between electron-rich perethylated pillar[5]arene and electron-deficient aromatic acceptors including 4-nitrobenzonitrile and 1,4-dinitrobenzene. These charge-transfer complexes with different colors show opposite color changes upon exposure to the vapors of 1-bromoalkanes (fading) and 2-bromoalkanes (deepening). Single-crystal structures incorporating X-ray powder diffraction and spectral analyses demonstrate that this on-off type vapochromic behavior is mainly attributed to the destruction (off) and reconstruction (on) of the charge-transfer interactions between perethylated pillar[5]arene and the acceptors, for which the competitive host-guest binding of 1-bromoalkanes and the solid-state structural transformation triggered by 2-bromoalkanes are respectively responsible. This work provides a simple colorimetric method for distinguishing positional isomers with similar physical and chemical properties.

Abstract Colorectal cancer (CRC) is generally characterized by a high prevalence of Fusobacterium nucleatum (F. nucleatum), a spindle‐shaped, Gram‐negative anaerobe pathogen derived from the oral cavity. This tumor‐resident microorganism has been closely correlated with the occurrence, progression, chemoresistance and immunosuppressive microenvironment of CRC. Furthermore, F. nucleatum can specifically colonize CRC tissues through adhesion on its surface, forming biofilms that are highly resistant to commonly used antibiotics. Accordingly, it is crucial to develop efficacious non‐antibiotic approaches to eradicate F. nucleatum and its biofilms for CRC treatment. In recent years, various antimicrobial strategies, such as natural extracts, inorganic chemicals, organic chemicals, polymers, inorganic‐organic hybrid materials, bacteriophages, probiotics, and vaccines, have been proposed to combat F. nucleatum and F. nucleatum biofilms. This review summarizes the latest advancements in anti‐F. nucleatum research, elucidates the antimicrobial mechanisms employed by these systems, and discusses the benefits and drawbacks of each antimicrobial technology. Additionally, this review also provides an outlook on the antimicrobial specificity, potential clinical implications, challenges, and future improvements of these antimicrobial strategies in the treatment of CRC.

Abstract Synthetic macrocycles have served as principal tools for supramolecular chemistry since their establishment, and the investigation of macrocycles‐aided organic‐inorganic hybrid nanomaterials has also attracted broad interest in chemistry and material communities during the past decade owing to their widespread applications in optical sensing, catalytic degradation, biomedicine, and other related fields. Herein, a new class of silver nanoparticles (AgNPs) modified by anionic water‐soluble [2]biphenyl‐extended pillar[6]arene (WBpP6), namely WBpP6‐AgNPs, is designed and synthesized through a facile one‐pot method. WBpP6‐AgNPs with good dispersion and stability exhibit efficient catalytic properties toward the hydrogenation of a series of aromatic nitro compounds and also show good performance in label‐free detection toward diquat.

A new supramolecular approach toward the reductive degradation of organic dyes by hybridizing hydrophilic hydrazide-pillar[5]arene (HP5A) as surface-modifiers with silver nanoparticles (AgNPs) has been demonstrated. The fabricated supramolecular hybrid nanomaterial (denoted as HP5A-AgNPs) with ideal mono-dispersity, improved stability, and smaller size, show high catalytic activity in boosting organic dyes degradation, as delivered by a broad spectrum of organic dyes, including rhodamine B, rhodamine 6G, methylene blue, and methyl orange. This work expands the application scope of macrocycles-derived organic-inorganic nanohybrids into catalytic degradation and environmental protection areas.

Abstract Developing smart room‐temperature phosphorescence (RTP) materials with facile and efficient strategies have attracted increasing attention. Herein, tunable RTP materials with two phosphorescent sources and stepwise enhanced phosphorescence in water are obtained through an in‐situ self‐assembly strategy based on the sensitization of phosphors by trimesic acid (TMA) through simple doping and the rigidification of phosphors by hydrogen‐bonded organic frameworks (HOFs). As expected, doped TMA+phosphors simultaneously promote the RTP emission of phosphors and maintain TMA phosphorescence. In‐situ assembled HOF(MA‐TMA)@phosphors facilitate smart RTP emission in water due to the coexistence of phosphorescent HOF(MA‐TMA) host and phosphors guest. Additionally, such RTP materials with good processability demonstrate the application potential in information security, benefitting from their varied afterglow lifetimes and easy luminous recognition in the darkness. This work will inspire the design of dual phosphorescent source RTP systems and provide new strategies for the development of smart RTP materials in water.

Abstract Aggregation‐induced emission (AIE), as an exciting photophysical phenomenon, has been regarded as one frontier research topic within both ranges of molecular luminescence and materials science over the last two decades. Since controllable molecular ensembles with particular morphologies and tunable functions can be elegantly constructed in the realm of supramolecular chemistry, the integration of supramolecular assembly and AIE systems can expectedly bring about luminescent materials with tunable emission and tailorable well‐ordered architectures. In this review, we will provide a summary of the creation and working mechanisms of AIE systems involving supramolecular systems that are driven by different supramolecular driving forces including hydrogen bonding, host−guest interactions, metal coordination, and π–π interactions. The morphological and photoluminescent features of these AIE‐active supramolecular assemblies will be elucidated, and the regulated fluorescence properties of the AIEgens induced by the assembling–disassembling processes will be discussed in detail.

Summary: Graphdiyne (GDY) as an emerging 2D carbon-network nanomaterial possesses many fascinating properties that lead to numerous exciting applications, but the use of GDY and its derivatives in the antibacterial field has not yet been discovered. In this study, we first report on the use and evaluation of GDY and graphdiyne oxide (GDYO) as antibacterial agents and propose the antibacterial mechanisms of GDY-based nanomaterials. GDYO has been synthesized via the surface oxidation of GDY, and the antibacterial activity of GDYO has been compared with that of GDY through a series of antibacterial tests. Surprisingly, surface oxidation endowed inert GDY with superior antibacterial capability against two representative bacterial models: Escherichia coli and Staphylococcus aureus. Antibacterial mechanism experiments disclose that the antibacterial function of GDYO is a result of reactive oxygen species-dependent oxidation stress when a dispersed GDYO suspension has a direct contact with bacteria especially under visible light irradiation. : Chemical Synthesis; Nanomaterials; Materials Characterization Subject Areas: Chemical Synthesis, Nanomaterials, Materials Characterization

Fluorescent N-doped carbon dots (CN-dots) covalently functionalized with carboxylatopillar[5]arene (CP[5]), namely CCDs, have been prepared the first time. Compared with CN-dots without pillarene units, the newly constructed fluorescent CCDs could recognize Fe3+ with high selectivity. Therefore, such CCDs can potentially serve as a promising chemical sensor for Fe3+ ions.

The study of aqueous-phase molecular recognition of artificial receptors is one of the frontiers in supramolecular chemistry since most biochemical processes and reactions take place in an aqueous medium and heavily rely on it. In this work, a water-soluble version of leggero pillar[5]arene bearing eight positively charged pyridinium moieties (CWP[5]L) was designed and synthesized, which exhibited good binding affinities with certain aliphatic sulfonate species in aqueous solutions. Significantly, control experiments demonstrate that the guest binding performance of CWP[5]L is superior to its counterpart water-soluble macrocyclic receptor in traditional pillararenes.

Abstract Agricultural chemicals have been widely utilized to manage pests, weeds, and plant pathogens for maximizing crop yields. However, the excessive use of these organic substances to compensate their instability in the environment has caused severe environmental consequences, threatened human health, and consumed enormous economic costs. In order to improve the utilization efficiency of these agricultural chemicals, one strategy that attracted researchers is to design novel eco‐friendly nanoplatforms. To date, numerous advanced nanoplatforms with functional components have been applied in the agricultural field, such as silica‐based materials for pesticides delivery, metal/metal oxide nanoparticles for pesticides/mycotoxins detection, and carbon nanoparticles for fertilizers delivery. In this review, the synthesis, applications, and mechanisms of recent eco‐friendly nanoplatforms in the agricultural field, including pesticides and mycotoxins on‐site detection, phytopathogen inactivation, pest control, and crops growth regulation for guaranteeing food security, enhancing the utilization efficiency of agricultural chemicals and increasing crop yields are highlighted. The review also stimulates new thinking for improving the existing agricultural technologies, protecting crops from biotic and abiotic stress, alleviating the global food crisis, and ensuring food security. In addition, the challenges to overcome the constrained applications of functional nanoplatforms in the agricultural field are also discussed.

Summary: Infectious endophthalmitis is a growing concern that causes irreversible intraocular tissue and optic nerve damage. Here, we report a theranostic nanoplatform based on UiO-66-NH2 to combine photodynamic therapy (PDT) and lipopolysaccharide (LPS) targeting through polypeptide (YVLWKRKRKFCFI-NH2) modification. Toluidine blue (TB), serving as a photosensitizer (PS), is loaded into UiO-66-NH2 nanoparticles (NPs) for both self-imaging and PDT functions. The accelerated TB release at pH 5.5 compared to pH 7.4 demonstrates the responsive drug release feature. In vitro antibacterial tests, including contact incubation-agar plate counting, bacterial live/dead staining, and scanning electron microscopy observations, confirm the utility of the TB@UiO-66-NH2@PEP&PEG NPs (UTPP NPs) in biofilms removal and sterilization of Pseudomonas aeruginosa and Staphylococcus epidermidis. Furthermore, the UTPP NPs also show good biocompatibility toward human retinal pigment epithelial cells, as well as in situ self-imaging property. Finally, an in vivo infectious endophthalmitis model supports the application of the UTPP NPs in infectious endophthalmitis treatment.

We construct a fluorescent supramolecular system (TPE-Q4⊂ DSP5) of excellent tolerance to a wide range of pH by the facile self-assembly of a new pillar[5]arene bearing disulfonated arms (DSP5) with an AIE-active tetraphenylethene-based tetratopic guest bearing four quaternary ammonium binding sites (TPE-Q4), which exhibits strong blue emission even in dilute aqueous solutions along with much higher quantum yield and longer fluorescence lifetime than TPE-Q4 itself. This appreciable property can be attributed to the supramolecular assembly-induced emission (SAIE) mechanism endowed by the host-guest inclusion complexation based on synthetic macrocycles. Remarkably, the enhanced fluorescence of the supramolecular assembly is quenched efficiently and exclusively by ferric ions in water with a high Stern–Volmer formula constant of 1.3 × 105 mol-1, demonstrating the excellent cation selectivity and visualized responsiveness in ion sensing and detection.

Recently, transition metal oxides, such as ruthenium oxide (RuO2), manganese dioxide (MnO2), nickel oxides (NiO) and cobalt oxide (Co3O4), have been widely investigated as electrode materials for pseudo-capacitors. In particular, these metal oxides with mesoporous structures have become very hot nanomaterials in the field of supercapacitors owing to their large specific surface areas and suitable pore size distributions. The high specific capacities of these mesoporous metal oxides are resulted from the effective contacts between electrode materials and electrolytes as well as fast transportation of ions and electrons in the bulk of electrode and at the interface of electrode and electrolyte. During the past decade, many achievements on mesoporous transition metal oxides have been made. In this mini-review, we select several typical nanomaterials, such as RuO2, MnO2, NiO, Co3O4 and nickel cobaltite (NiCo2O4), and briefly summarize the recent research progress of these mesoporous transition metal oxides-based electrodes in the field of supercapacitors.

Ventilator-associated pneumonia (VAP) is a common nosocomial infection among intensive care unit (ICU) patients. Pseudomonas aeruginosa (PA) is the most common multidrug-resistant Gram-negative pathogen and VAP caused by PA carries a high rate of morbidity and mortality. This study examined the molecular mechanism of PA VAP-induced lung injury. C57BL/6 wild-type (WT) mice and JNK1 knockout (JNK1-/-) mice received mechanical ventilation (MV) for 3 h at 2 days after receiving nasal instillation of PA. The WT and JNK1-/- mice also received MV after the induction of lung injury by instillation of supernatants from PA-stimulated alveolar macrophages (AMs). AMs isolated from WT, IκB-kinase (IKK)βΔMye (IKKβ was selectively deleted in macrophages), and JNK1-/- mice were ex vivo stimulated with live PA and supernatants were collected for cytokine assay. Intranasal instillation of 106 PA enhanced MV-induced NF-κB DNA binding activity in the lungs and nitrite levels in BALF. MV after PA instillation significantly increased the expression of ICAM and VCAM in the lungs and TNF-α, IL-1β, and IL-6 levels in bronchoalveolar lavage fluid (BALF) of WT mice, but not in JNK1-/- mice. MV after supernatant instillation induced more total protein concentration in BALF and neutrophil sequestration in the lungs in WT mice than JNK1-/- mice and cytokine assay of supernatants indicated that TNF-α is a critical regulator of PA VAP-induced lung injury. Ex vivo PA stimulation induced TNF-α production by AMs from WT as well as JNK1-/- mice but not IKKβΔMye mice. In summary, PA colonization plays an important role in PA VAP-induced lung injury through the induction of JNK1-mediated inflammation. These results suggest that the pathogenesis mechanism of PA VAP involves production of TNF-α through activation of IKK/NF-κB pathways in AMs and JNK signaling pathway in the lungs.

Traditional ionic liquids (ILs) catalysts suffer from the difficulty of product purification and can only be used in homogeneous catalytic systems. In this work, by reacting ILs with co-catalyst (ZnBr2), we successfully converted three polyether imidazole ionic liquids (PIILs), i.e., HO-[Poly-epichlorohydrin-methimidazole]Cl (HO-[PECH-MIM]Cl), HOOC-[Poly-epichlorohydrin-methimidazole]Cl (HOOC-[PECH-MIM]Cl), and H2N-[Poly-epichlorohydrin-methimidazole]Cl (H2N-[PECH-MIM]Cl), to three composite PIIL materials, which were further immobilized on ZSM-5 zeolite by chemical bonding to result in three immobilized catalysts, namely ZSM-5-HO-[PECH-MIM]Cl/[ZnBr2], ZSM-5-HOOC-[PECH-MIM]Cl/[ZnBr2], and ZSM-5-H2N-[PECH-MIM]Cl/[ZnBr2]. Their structures, thermal stabilities, and morphologies were fully characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The amount of composite PIIL immobilized on ZSM-5 was determined by elemental analysis. Catalytic performance of the immobilized catalysts was evaluated through the catalytic synthesis of propylene carbonate (PC) from CO2 and propylene oxide (PO). Influences of reaction temperature, time, and pressure on catalytic performance were investigated through the orthogonal test, and the effect of catalyst circulation was also studied. Under an optimal reaction condition (130 °C, 2.5 MPa, 0.75 h), the composite catalyst, ZSM-5-HOOC- [PECH-MIM]Cl/[ZnBr2], exhibited the best catalytic activity with a conversion rate of 98.3% and selectivity of 97.4%. Significantly, the immobilized catalyst could still maintain high heterogeneous catalytic activity even after being reused for eight cycles.

The fabrication of smart materials is gradually becoming a research focus in nanotechnology and materials science. An important criterion of smart materials is the capacity of stimuli-responsiveness, while another lies in selective recognition. Accordingly, supramolecular host-guest chemistry has proven a promising support for building intelligent, responsive systems; hence, synthetic macrocyclic hosts, such as calixarenes, cucurbiturils, cyclodextrins, and pillararenes, have been used as ideal building blocks. Meanwhile, manipulating and harnessing light artificially is always an intensive attempt for scientists in order to meet the urgent demands of technological developments. Fluorescence resonance energy transfer (FRET), known as a well-studied luminescent activity and also a powerful tool in spectroscopic area, has been investigated from various facets, of which the application range has been broadly expanded. In this review, the innovative collaboration between FRET and supramolecular macrocyclic chemistry will be presented and depicted with typical examples. Facilitated by the dynamic features of supramolecular macrocyclic motifs, a large variety of FRET systems have been designed and organized, resulting in promising optical materials with potential for applications in protein assembly, enzyme assays, diagnosis, drug delivery monitoring, sensing, photosynthesis mimicking and chemical encryption.

Innovative design of smart organic materials is of great importance for the advancement of modern technology. Macrocycle hosts, possessing cyclic skeletons, intrinsic cavities, and specific guest binding properties, have demonstrated pronounced potential for the elaborate fabrication of a variety of functional organic materials with smart stimuli-responsive characteristics. In this tutorial review, we outline the current development of smart organic materials based on macrocycle hosts as key building blocks, focusing on the design principles and functional mechanisms of the tailored systems. Three main types of macrocycle-based smart organic materials are exemplified as follows according to the distinct forms of construction patterns: (1) supramolecular polymeric materials and nanoassemblies; (2) adaptive molecular crystals; (3) smart porous organic materials. The responsive performances of macrocycle-containing smart materials in versatile aspects, including mechanically adaptive polymers, soft optoelectronic devices, data encryption, drug delivery systems, artificial transmembrane channels, crystalline-state gas adsorption/separation, and fluorescence sensing, are illustrated by discussing the representative studies as paradigms, where the roles of macrocycles in these systems are highlighted. We also provide in the conclusion part the perspectives and remaining challenges in this burgeoning field. [ABSTRACT FROM AUTHOR]

The syntheses of bridged bis (beta-cyclodextrin (CD)) s with different spacers and their molecular recognition thermodynamics and solution structures upon inclusion complexation with representative steroids are reported. Studies disclosed the enhanced binding ability and molecular selectivity of steroid by bis (beta-CD) and established the correlation between thermodynamic parameters and solution structure in the complexation of bridged bis (beta-CD) and steroid.

The article presents a new approach, which employs different types of molecular machines for the synthesis of the dual-controlled nanoparticles (DCNPs). The manufactured DCNPs are shown to exhibit an AND logic, while behaving as a sophisticated controllable release system.

A versatile synthetic strategy is described that is used for preparing doubly threaded, bistable [c2]daisy chain compounds. Kinetics measurements have shown that the acid/base-promoted extension/contraction movements of the polymeric [c2]daisy chain are faster than those of its monomeric counterpart.

A series of inclusion complexes of alpha-, beta-, and gamma-cyclodextrins (CDs) with 4,4'-dipyridine is prepared and their assembly behaviors in the presence of transition-metal ions is investigated. The results show that the volume of CD used not only determines the inclusion complexation stoichiometry between the CD and 4,4'-dipyridine but also predominates the morphology of the resulting polypseudorotaxanes.

Thermodynamics and kinetics of the inclusion complexation of some bile salts with native beta-cyclodextrins (CD) by nuclear magnetic resonance (NMR) spectroscopy is described. It is concluded that the thermodynamically, the enhanced molecular recognition ability resulted from enthalpy gain with smaller entropy loss.

The inclusion complexation behaviors of a series of 6-O-(p-substituted phenyl)-modified beta-cyclodextrin derivatives are synthesized in an aqueous solution and their self-assembling behavior in the solid state are compared. This comparative study is conducted using NMR spectroscopy, microcalorimetry, crystallography, and scanning tunneling microscopy.

The design, synthesis and operation of a novel, biocompatible controlled-release motif, named as snap-top covered silica nanocontainers (SCSNs), are described. The results are shown to be a biocompatible controlled release system that has exploited enzymatic specificity.

Peroxidase mimetic catalytic atom transfer radical polymerization (ATRP) was first used to install tertiary amine-functionalized polymer brushes on the surface of mesoporous silica nanoparticles (MSNs) in a facile and highly efficient manner. Poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) brushes-grafted MSNs were fabricated by biocompatible deuterohemin-β-Ala-His-Thr-Val-Glu-Lys (DhHP-6)-catalyzed surface-initiated ATRP (SI-ATRP). The resulting organic-inorganic hybrid nanocarriers were fully characterized by Fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), SEM, TEM, Elemental analysis, Zeta-potential, and N2 adsorption-desorption isotherms, which demonstrated the successful coating of pH-responsive polymers on the MSN surface. Rhodamine 6G (Rh6G) dyes were further loaded within the mesopores of this nanocarrier, and the release of Rh6G out of MSNs in a controlled fashion was achieved upon lowing the solution pH. The electrostatic repulsion of positively-charged tertiary ammonium of PDMAEMAs in acidic environments induced the stretching out of polymer brushes on MSN surfaces, thus opening the gates to allow cargo diffusion out of the mesopores of MSNs. [ABSTRACT FROM AUTHOR]

In this feature article, we give an overview of the preparation and application of self-assembled architectures based on an emerging area of polymers, i.e., poly(glycidyl methacrylate)s (PGMAs) and their derivatives. A series of PGMA-based aggregates and hybrids, such as micelles, reverse micelles, capsules, nanoparticles, and inorganic-organic hybrid materials, has been constructed, and diverse morphologies were formed, driven by hydrophobic interactions, hydrogen bonding, ionic complexation, host-guest interactions, etc. In particular, the assemblies have shown great potential applications as drug vectors, gene vectors, solubilizing agents, antimicrobial agent, and so forth. Herein, the general guidelines are elaborately selected from literature examples and partially from our own. Although still in its infancy, self-assembly of PGMA-based polymers is expected to become a hot topic in polymer chemistry and materials science. [ABSTRACT FROM AUTHOR]

Ditopic pillarene-based fluorescence enhancement material induced by [c2]daisy chain formation has been successfully fabricated. The highly fluorescent smart material exhibits great adaptivity and can act as a multi-responsive supramolecular sensor. [ABSTRACT FROM AUTHOR]

A tetraphenylethene-bridged pillarene tetramer with aggregationinduced emission properties forms an A4/B2-type supramolecular polymer and a gel with a symmetric neutral guest linker, showing a remarkable fluorescence emission enhancement in solution and the solid state and a good responsiveness to temperature and solvent composition. [ABSTRACT FROM AUTHOR]

A gold nanodisk array, coated with bistable, redox-controllable [2]rotaxane molecules, when exposed to chemical oxidants and reductants, undergoes switching of its plasmonic properties reversibly. By contrast, (i) bare gold nanodisks and (ii) disks coated with a redox-active, but mechanically inert, control compound do not display surface-plasmon-based switching. Along with calculations based on time-dependent density functional theory, these experimental observations suggest that the nanoscale movements within surface-bound “molecular machines” can be used as the active components in plasmonic devices. [ABSTRACT FROM AUTHOR]

Systematic investigation into the chemical etiology of ribose has led to the discovery of glycerol nucleic acid (GNA) and threose nucleic acid (TNA) as possible progenitor candidates of RNA in the origins of life. Coupled with their chemical simplicity, polymers for both systems are capable of forming stable Watson-Crick antiparallel duplex structures with themselves and RNA, thereby providing a mechanism for the transfer of genetic information between successive genetic systems. Investigation into whether both polymers arose independently or descended from a common evolutionary pathway would provide additional constraints on models that describe the emergence of a hypothetical RNA world. Here we show by thermal denaturation that complementary GNA and TNA mixed sequence polymers are unable, even after prolonged incubation times, to adopt stable helical structures by intersystem cross-pairing. This experimental observation suggests that GNA and TNA, whose structures derive from one another, were not consecutive polymers in the same evolutionary pathway to RNA. [ABSTRACT FROM AUTHOR]

Three cyclodextrin-based complexes, 1-3, bearing external coordination sites for metal cations were prepared in satisfactory yields (over 50%) by reactions of α-, β-, and γ-cyclodextrins with 4,4'-dipyridine in aqueous solutions. Subsequently, these inclusion complexes were further assembled to form linear polypseudorotaxanes 4-6 through the coordination linkage of Ni(II) or Cu(II) ions, and their assembly behaviors were comprehensively investigated in both solutions and the solid state by means of ¹H NMR, FT-IR, UV-vis spectroscopy, conductivity titration, powder X-ray diffraction patterning, thermogravimetric and differential thermal analysis, scanning electron microscopy, scanning tunneling microscopy, and transmission electron microscopy. The results showed that these polypseudorotaxanes existed as individual linear arrays at a low concentration but tended to form polymeric rodlike fibers at a relatively high concentration. Significantly, the volume of the cyclodextrin cavity used not only determined the inclusion complexation stoichiometry between cyclodextrin and 4,4'-dipyridine but also predominated the morphology of resulting polypseudorotaxanes. [ABSTRACT FROM AUTHOR]

A series of bridged bis(β-cyclodextrin(CD))s (2-7) were synthesized, i.e., bridged bis(β-CD)s 2 and 3 bearing binaphthyl or biquinoline tethers and bridged bis(β-CD)s 4-7 possessing dithiobis(benzoyl) tether, and their complex stability constants (KS), enthalpy (ΔH°), and entropy changes (ΔS°) for the 1:2 inclusion complexation with representative steroids, deoxycholate, cholate, glycocholate, and taurocholate, have been determined in an aqueous phosphate buffer solution of pH 7.20 at 298.15 K by means of titration microcalorimetry. The original conformations of bridged bis(βcyclodextrin)s were investigated by circular dichroism and ¹H ROESY spectroscopy. Structures of the inclusion complexes between steroids and bridged bis(β-CD)s in solution were elucidated by 2D NMR experiments, indicating that anionic groups of two steroid molecules penetrate, respectively, into the two hydrophobic CD cavities in one 6,6'-bridged bis(β-CD) molecule from the secondary rim to give a 1:2 binding mode upon inclusion complexation. The results obtained from titration microcalorimetry and 2D NMR experiments jointly demonstrate that bridged bis(β-CD)s 2, 3 and 5-7 tethered by protonated amino group possessing different substituted groups can enhance not only the molecular binding ability toward steroids by electrostatic interaction but also molecular selectivity. Thermodynamically, the resulting 1:2 bis(β-CD)-steroid complexes are formed by an enthalpy-driven process, accompanied by smaller entropy loss. The increased complex stability mainly results from enthalpy gain, accompanied by large conformational change and extensive desolvation effects for the 1:2 inclusion complexation between bis(β-CD)s and steroids. [ABSTRACT FROM AUTHOR]