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Mechanical nonreciprocity, or the asymmetric transmission of mechanical quantities between two points in space, is crucial for developing systems that can guide, damp, and control mechanical energy. We report a uniform composite hydrogel that displays substantial mechanical nonreciprocity, owing to direction-dependent buckling of embedded nanofillers. This material exhibits an elastic modulus more than 60 times higher when sheared in one direction compared with the opposite direction. Consequently, it can transform symmetric vibrations into asymmetric ones that are applicable for mass transport and energy harvest. Furthermore, it exhibits an asymmetric deformation when subjected to local interactions, which can induce directional motion of various objects, including macroscopic objects and even small living creatures. This material could promote the development of nonreciprocal systems for practical applications such as energy conversion and biological manipulation.

Ultrafast water permeation in aquaporins is promoted by their hydrophobic interior surface. Polytetrafluoroethylene has a dense fluorine surface, leading to its strong water repellence. We report a series of fluorous oligoamide nanorings with interior diameters ranging from 0.9 to 1.9 nanometers. These nanorings undergo supramolecular polymerization in phospholipid bilayer membranes to form fluorous nanochannels, the interior walls of which are densely covered with fluorine atoms. The nanochannel with the smallest diameter exhibits a water permeation flux that is two orders of magnitude greater than those of aquaporins and carbon nanotubes. The proposed nanochannel exhibits negligible chloride ion (Cl – ) permeability caused by a powerful electrostatic barrier provided by the electrostatically negative fluorous interior surface. Thus, this nanochannel is expected to show nearly perfect salt reflectance for desalination.

The assembly of donor–acceptor molecules via charge transfer (CT) interactions gives rise to highly ordered nanomaterials with appealing electronic properties. Here, we present the synthesis and bulk co-assembly of pyrene (Pyr) and naphthalenediimide (NDI) functionalized oligodimethylsiloxanes (oDMS) of discrete length. We tune the donor–acceptor interactions by connecting the pyrene and NDI to the same oligomer, forming a heterotelechelic block molecule (NDI-oDMSPyr), and to two separate oligomers, giving Pyr and NDI homotelechelic block molecules (Pyr-oDMS and NDI-oDMS). Liquid crystalline materials are obtained for binary mixtures of Pyr-oDMS and NDI-oDMS, while crystallization of the CT dimers occurred for the heterotelechelic NDI-oDMS-Pyr block molecule. The synergy between crystallization and phase-segregation coupled with the discrete length of the oDMS units allows for perfect order and sharp interfaces between the insulating siloxane and CT layers composed of crystalline CT dimers. We were able to tune the lamellar domain spacing and donor–acceptor CT interactions by applying pressures up to 6 GPa on the material, making the system promising for soft-material nanotechnologies. These results demonstrate the importance of the molecular design to tune the CT interactions and stability of a CT material., A robust, soft material held together by charge transfer interactions is developed. The nanostructure dimensions and material properties can be tuned by molecular design or pressure.

What particular mechanical properties can be expected for materials composed of interlocked backbones has been a long-standing issue in materials science since the first reports on polycatenane and polyrotaxane in the 1970s1–3. Here we report a three-dimensional porous metal–organic crystal, which is exceptional in that its warps and wefts are connected only by catenation. This porous crystal is composed of a tetragonal lattice and dynamically changes its geometry upon guest molecule release, uptake and exchange, and also upon temperature variation even in a low temperature range. We indented4 the crystal along its a/b axes and obtained the Young’s moduli of 1.77 ± 0.16 GPa in N,N-dimethylformamide and 1.63 ± 0.13 GPa in tetrahydrofuran, which are the lowest among those reported so far for porous metal–organic crystals5. To our surprise, hydrostatic compression showed that this elastic porous crystal was the most deformable along its c axis, where 5% contraction occurred without structural deterioration upon compression up to 0.88 GPa. The crystal structure obtained at 0.46 GPa showed that the catenated macrocycles move translationally upon contraction. We anticipate our mechanically interlocked molecule-based design to be a starting point for the development of porous materials with exotic mechanical properties. For example, squeezable porous crystals that may address an essential difficulty in realizing both high abilities of guest uptake and release are on the horizon. A rubber-like, metal–organic crystal is reported with a mechanically interlocked catenane backbone, which could allow for easy guest molecule uptake and release.

Can commodity polymers are made to be healable just by blending with self-healable polymers? Here we report the first study on the fundamental aspect of this practically challenging issue. Poly(ether thiourea) (PTUEG3; Tg = 27 °C) reported in 2018 is extraordinary in that it is mechanically robust but can self-heal even at 12 °C. In contrast, poly(octamethylene thiourea) (PTUC8; Tg = 50 °C), an analogue of PTUEG3, cannot heal below 92 °C. We found that their polymer blend self-healed in a temperature range above 32 °C even when its PTUEG3 content was only 20 mol %. Unlike PTUEG3 alone, this polymer blend, upon exposure to high humidity, barely plasticized, keeping its excellent mechanical properties due to the non-hygroscopic nature of the PTUC8 component. CP/MAS 13C NMR analysis revealed that the polymer blend was nanophase-separated, which possibly accounts for why such a small amount of PTUEG3 provided the polymer blend with humidity-tolerant self-healable properties.

We developed a photoreactive molecular glue, BPGlue-N3, which can provide a universal strategy to enhance the efficacy of DNA aptamers by temporary-to-permanent stepwise stabilization of their conjugates with target proteins. As a proof-of-concept study, we applied BPGlue-N3 to the SL1 (DNA aptamer)/c-Met (target protein) conjugate system. BPGlue-N3 can adhere to and temporarily stabilize this aptamer/protein conjugate multivalently using its guanidinium ion (Gu+) pendants that form a salt bridge with oxyanionic moieties (e.g., carboxylate and phosphate) and benzophenone (BP) group that is highly affinitive to DNA duplexes. BPGlue-N3 is designed to carry a dual-mode photoreactivity; upon exposure to UV light, the temporarily stabilized aptamer/protein conjugate reacts with the photoexcited BP unit of adhering BPGlue-N3 and also a nitrene species, possibly generated by the BP-to-N3 energy transfer in BPGlue-N3. We confirmed that SL1, covalently conjugated with c-Met, hampered the binding of hepatocyte growth factor (HGF) onto c-Met, even when the SL1/c-Met conjugate was rinsed prior to the treatment with HGF, and suppressed cell migration caused by HGF-induced c-Met phosphorylation.

In stacking-based supramolecular polymerization, chiral hydrogen bonding (H-bonding) monomers often prefer to adapt a homochiral monomer sequence. Herein, we investigated the polymerization of a chiral thiophene-fused cyclooctatetraene (COT) as a novel nonplanar-core monomer and found the first example of the formation of an alternating heterochiral supramolecular copolymer. Although single enantiomer (-) or (+)-COT alone did not polymerize, when (-) and (+)-COT were mixed together, supramolecular polymerization took place to give a stereochemically alternating copolymer. By means of the microcrystal electron crystallography of a shorter side-chained COT analogue, we found that the resulting heterochiral supramolecular copolymer adapted an alternating arrangement of H-bonded and polar π-stacked parts. A computational study using density-functional theory (DFT) suggested that such an alternating heterochiral preference occurs because it allows two thiophene amide moieties facing each other to effectively cancel their in-plane dipole moments.

Here we report a bio-adhesive porous organic module (Glue COF) composed of hexagonally packed 1D nanopores based on a covalent organic framework. The nanopores are densely decorated with guanidinium ion (Gu+ ) pendants capable of forming salt bridges with oxyanionic species. Glue COF strongly adheres to biopolymers through multivalent salt-bridging interactions with their ubiquitous oxyanionic species. By taking advantage of its strong bio-adhesive nature, we succeeded in creating a gate that possibly opens the nanopores through a selective interaction with a reporter chemical and releases guest molecules. We chose calmodulin (CaM) as a gating component that can stably entrap a loaded guest, sulforhodamine B (SRB), within the nanopores (CaM COF⊃SRB). CaM is known to change its conformation on binding with Ca2+ ions. We confirmed that mixing CaM COF⊃SRB with Ca2+ resulted in the release of SRB from the nanopores, whereas the use of weakly binding Mg2+ ions resulted in a much slower release of SRB.

Using a photochemically fluttering thiophene-fused cyclooctatetraene derivative (

Here, we report a medium-to-polymer anomalous chiral transfer in the supramolecular polymerization of a tetraphenylporphyrin-based achiral hydrogen-bonding monomer (TPP) in a chiral medium of 5-cyanobiphenyl CB*. A mixture of TPP in (R)-CB* ([TPP]=7.7 mol %) at 40 °C gave a columnar oblique LC mesophase, where the individual columns were composed of an optically active helical supramolecular polymer of TPP as a consequence of a successful medium-to-polymer chiral transfer. Meanwhile, upon dilution of CB* with achiral 5-cyanobiphenyl CB, the optical activity of the system showed an anomalous bell-shaped dependency on the composition of CB*/CB, where the g

Although various biomimetic soft materials that display structural hierarchies and stimuli responsiveness have been developed from organic materials, the creation of their counterparts consisting entirely of inorganic materials presents an attractive challenge, as the properties of such materials generally differ from those of living organisms. Here, we have developed a hydrogel consisting of inorganic nanosheets (14 wt%) and water (86 wt%) that undergoes thermally induced reversible and abrupt changes in its internal structure and mechanical elasticity (23-fold). At room temperature, the nanosheets in water electrostatically repel one another and self-assemble into a long-periodic lamellar architecture with mutually restricted mobility, forming a physical hydrogel. Upon heating above 55 °C, the electrostatic repulsion is overcome by competing van der Waals attraction, and the nanosheets rearrange into an interconnected 3D network of another hydrogel. By doping the gel with a photothermal-conversion agent, the gel-to-gel transition becomes operable spatiotemporally on photoirradiation., Inorganic soft materials are an attractive concept but challenging to make. Here the authors have developed a hydrogel consisting of inorganic nanosheets (14 wt%) and water (86 wt%) that undergoes thermally induced reversible and abrupt changes in its internal structure and mechanical elasticity (23-fold).

Water molecules within a thin hydration layer, spontaneously generated on hydrophobic protein surfaces, are reported to form a poorly dynamic network structure. However, how such a water network affects the conformational change dynamics of polar groups has never been explored, although such polar groups play a critical role in protein-protein and protein-ligand interactions. In the present work, we utilized as model protein surfaces a series of self-assembled monolayers (SAMs) appended with polar (Fmoc) or ionic (FITC) fluorescent head groups that were tethered via a 1.5-nm-long flexible oligoether chain to a hydrophobic silicon wafer surface, which was densely covered with paraffinic chains. We found that, not only in deionized water but also in aqueous buffer, these oligoether-appended head groups at ambient temperatures both displayed an anomalously slow conformational change, which required ∼10 h to reach a thermodynamically equilibrated state. We suppose that these behaviors reflect the poorly dynamic and low-permittivity natures of the thin hydration layer.

Since the first polymers were discovered, scientists have debated their structures. Before Hermann Staudinger published the brilliant concept of macromolecules, polymer properties were generally believed to be based on the colloidal aggregation of small particles or molecules. From 1920 onwards, polymers and macromolecules are synonymous with each other; i. e. materials made by many covalent bonds connecting monomers in 2 or 3 dimensions. Although supramolecular interactions between macromolecular chains are evidently important, e. g. in nylons, it was unheard of to proposing polymeric materials based on the interaction of small molecules. Breakthroughs in supramolecular chemistry, however, showed that polymer materials can be made by small molecules using strong directional secondary interactions; the field of supramolecular polymers emerged. In a way, we have come full circle. In this essay we give a personal story about the birth of supramolecular polymers, with special emphasis on their structures, way of formation, and the dynamic nature of their bonding. The adaptivity of supramolecular polymers has become a major asset for novel applications, e. g. in the direction for the sustainable use of polymers, but also in biomedicine and electronics as well as self-healing materials. The lessons learned in the past years include aspects that forecast a bright future for the use of supramolecular interactions in polymer materials in general and for supramolecular polymers in particular. In order to give full tribute to Staudinger in the year celebrating 100 years of macromolecules, we will show that many of the concepts of macromolecular polymers apply to supramolecular polymers, with only one important difference with fascinating consequences: the dynamic nature of the bonds that form polymer chains.

Significance As the formation of quasicrystalline ordering in both metal alloys and soft matters reinforces the scale-invariance principle, however, it remains unknown that why metallic quasicrystals prefer decagonal quasicrystalline (DQC, 10-fold) ordering, and the condensed soft maters only exhibit dodecagonal quasicrystalline (DDQC, 12-fold) ordering. By tuning the self-sorting ability in a pair of giant molecules, the well-mixed binary blends generate a metastable DQC phase and corresponding unprecedent phase sequence (DQC → DDQC → Frank–Kasper σ) during thermal annealing. These peculiar assembling behaviors result from interplays of submesoatomic and mesoatomic packings. Reducing the self-sorting strength has induced an extra complexity in the sub-mesoatomic packings of giant molecules, which further influences the clustering on the mesoatomic level., The quasiperiodic structures in metal alloys have been known to depend on the existence of icosahedral order in the melt. Among different phases observed in intermetallics, decagonal quasicrystal (DQC) structures have been identified in many glass-forming alloys yet remain inaccessible in bulk-state condensed soft matters. Via annealing the mixture of two giant molecules, the binary system assemblies into an axial DQC superlattice, which is identified comprehensively with meso-atomic accuracy. Analysis indicates that the DQC superlattice is composed of mesoatoms with an unusually broad volume distribution. The interplays of submesoatomic (molecular) and mesoatomic (supramolecular) local packings are found to play a crucial role in not only the formation of the metastable DQC superlattice but also its transition to dodecagonal quasicrystal and Frank–Kasper σ superlattices.

2020 was a very special year for polymer science as the 100-year anniversary of its initiation by Staudinger. The past 100 years have been a prosperous time for polymer science, filled with discovery and innovation. Since plastics are lightweight, mechanically robust, and cheap, their use has proliferated, becoming pervasive in all sectors of society and ushering in the so-called heyday of plastics. At the same time, however, the plastics and rubbers developed by polymer science have caused catastrophic damage to the environment as long-lasting wastes continue to accumulate in the disposable age. Incinerating these materials generates carbon dioxide, which accelerates global warming while dumping them into the ocean results in their eventual disintegration into microplastics, small pieces that are consumed and accumulate in the food chain. As of 2015, only 9% of the 6300 million metric tons of plastics produced had been recycled,1 and unless far-reaching policies are adopted in the next decade to change the social structure that has so far been dependent on disposable polymers, global warming will continue to accelerate and it will certainly be difficult to pass on livable earth to future generations. Although this crisis is widely acknowledged, society has thus far been unable to give up such convenient and cheap materials. If we fail to shift our economic priorities or invent new materials as alternatives, it will be impossible to escape from this plastic world.

Just like in living organisms, if precise coherent operation of tiny movable components is possible, one may generate a macroscopic mechanical motion. Here we report that ~1010 pieces of colloidally dispersed nanosheets in aqueous media can be made to operate coherently to generate a propagating macroscopic wave under a non-equilibrium state. The nanosheets are initially forced to adopt a monodomain cofacial geometry with a large and uniform plane-to-plane distance of ~420 nm, where they are strongly correlated by competitive electrostatic repulsion and van der Waals attraction. When the electrostatic repulsion is progressively attenuated by the addition of ionic species, the nanosheets sequentially undergo coherent motions, generating a propagating wave. This elaborate wave in time and space can transport microparticles over a long distance in uniform direction and velocity. The present discovery may provide a general principle for the design of macroscopically movable devices from huge numbers of tiny components., Tiny movable components could generate macroscopic mechanical motion if precise coherent operation can be exerted simultaneously. Here, the authors demonstrate this by using 10^10 pieces of colloidally dispersed nanosheets to generate wave under non-equilibrium state.

Ultralong organic phosphorescence (UOP) has aroused enormous interest in recent years. UOP materials are mainly limited to crystals or rigid host-guest systems. Their poor processability and mechanical properties critically hamper practical applications. Here, we reported a series of ultralong phosphorescent foams with high mechanical strength. Phosphorescence lifetime of the foam can reach up to 485.8 ms at room temperature. Impressively, lightweight gelatin foam can bear a compressive pressure of 4.44 MPa. Moreover, phosphorescence emission of polymer foam can be tuned from blue to orange through varying the excitation wavelength. Experimental data and theoretical calculations revealed that ultralong phosphorescence was ascribed to the fixation of multiple hydrogen bonds to the clusters of carbonyl groups. These results will allow for expanding the scope of luminescent foams, providing an ideal platform for developing ultralong phosphorescent materials with high mechanical strength.

Multicomponent crystallization is universally important in various research fields including materials science as well as biology and geology, and presents new opportunities in crystal engineering. This process includes multiple kinetic and thermodynamic events that compete with each other, wherein "external triggers" often help the system select appropriate pathways for constructing desired structures. Here we report an unprecedented finding that a lattice strain accumulated with the growth of a crystal serves as an "internal trigger" for pathway selection in multicomponent crystallization. We discovered a "spontaneous" crystal transition, where the kinetically preferred layered crystal, initially formed by excluding the pillar component, carries a single dislocation at its geometrical center. This crystal "spontaneously" liberates a core region to relieve the accumulated lattice strain around the dislocation. Consequently, the liberated part becomes dynamic and enables the pillar ligand to invade the crystalline lattice, thereby transforming into a thermodynamically preferred pillared-layer crystal.

PbS square superstructures are formed by the oriented assembly of PbS quantum dots (QDs), reflecting the facet structures of each QD. In the square assembly, the quantum dots are highly oriented, in sharp contrast to the conventional hexagonal QD assemblies, in which the orientation of QDs is highly disordered, and each QD is connected through ligand molecules. Here, we measured the transport properties of the oriented assembly of PbS square superstructures. The combined electrochemical doping studies by electric double layer transistor (EDLT) and spectroelectrochemistry showed that more than fourteen electrons per quantum dot are introduced. Furthermore, we proved that the lowest conduction band is formed by the quasi-fourth degenerate quantized (1Se) level in the PbS QD square superstructures.

Although mechanically robust polymer materials had not been thought to self-heal, we recently found that poly(ether thiourea) PTUEG3, which is a glassy polymer with high mechanical strength, self-heals even at ambient temperatures. This finding updated the above preconception. Nevertheless, it should also be noted that PTUEG3, under high humidity, absorbs water and is plasticized to lose its mechanical strength. Humidity-induced plasticization is a general problem for polymers with polar groups. Herein, we report that PTUEG3, if designed by copolymerization to contain only 10 mol % of a dicyclohexylmethane (Cy2M) thiourea unit (TUCy2M), serves as a humidity-tolerant, mechanically robust polymer material that can self-heal at ambient temperatures. This copolymer contained, in its ether thiourea (TUEG3)-rich domain, a humidity-tolerant, noncovalently cross-linked 3D network with mechanical robustness formed by stacking of the Cy2M group. The present work provides a promising design strategy for mechanically robust, self-healable polymers usable under high humidity.

A layered metal-organic framework (MOF) comprising extra-large nanographene sheets, HBCMOF, was successfully synthesized using a dicarboxylic acid derivative of hexa-peri-hexabenzocoronene (HBCLH2), and its structure was characterized by single-crystal X-ray diffraction analysis. The crystal structure shows that 2D layers composed of a dinuclear Zn2+ complex unit and HBCL are located on top of each other through multiple weak interlayer bonds, affording HBCMOF, having three dimensionally connected nanopores with large nanographene surfaces. The HBC-based nanographene sheets are anchored to the MOF framework via two zinc carboxylate linkages and therefore have an axial rotational freedom. The sorption isotherms of gaseous molecules such as carbon dioxide and hydrocarbons (acetylene, propane, propylene, benzene, and cyclohexane) on HBCMOF all displayed a hysteretic profile with reversible structural changes, as observed by in situ powder X-ray diffraction studies.

Although chirality has been recognized as an essential entity for life, it still remains a big mystery how the homochirality in nature emerged in essential biomolecules. Certain achiral motifs are known to assemble into chiral nanostructures. In rare cases, their absolute geometries are enantiomerically biased by mirror symmetry breaking. Here we report the first example of asymmetric catalysis by using a mirror symmetry-broken helical nanoribbon as the ligand. We obtain this helical nanoribbon from a benzoic acid appended achiral benzene-1,3,5-tricarboxamide by its helical supramolecular assembly and employ it for the Cu2+-catalyzed Diels–Alder reaction. By thorough optimization of the reaction (conversion: > 99%, turnover number: ~90), the enantiomeric excess eventually reaches 46% (major/minor enantiomers = 73/27). We also confirm that the helical nanoribbon indeed carries helically twisted binding sites for Cu2+. Our achievement may provide the fundamental breakthrough for producing optically active molecules from a mixture of totally achiral motifs., If asymmetric catalysts were available by mirror symmetry breaking, an important insight may be given to how the biomolecular homochirality emerged in nature. Here, the authors report the first example of asymmetric catalysis by employing mirror symmetry-broken helical nanoribbons as the ligand.

We recently developed a mechanically anisotropic hydrogel with a large internal electrostatic repulsion. The hydrogel is embedded with negatively charged titanate nanosheets that are cofacially oriented by a magnetic field. Because of the anisotropic electrostatic repulsion between the nanosheets, this hydrogel exhibits a large elastic modulus when compressed orthogonal to the nanosheet plane. In this paper, we systematically investigate how the intensity of the electrostatic repulsion affects the internal structure and mechanical property of this anisotropic hydrogel, where the free-ion concentration in the hydrogel medium was the key parameter for moderating the electrostatic repulsion due to its screening effect. With gradually changing the free-ion concentration in the hydrogel, nanoscopic arrangement and mesoscopic domain structure of the nanosheets were characterized by two-dimensional small-angle X-ray scattering (2D SAXS) and confocal laser scanning microscopy (CLSM), respectively. Furthermore, an anisotropic mechanical property of the hydrogel was evaluated by compression test. These results reveal that extensive deionization of the hydrogel medium and the resultant maximization of the electrostatic repulsion induces the nanosheets to adopt a monodomain lamellar structure that occupies the whole space of the hydrogel, thereby enhancing the mechanical anisotropy of the hydrogel.

Transferrin (Tf) is known to induce transcytosis, which is a consecutive endocytosis/exocytosis event. We developed a Tf-appended nanocaplet (TfNC⊃siRNA) for the purpose of realizing siRNA delivery into deep tissues and RNA interference (RNAi) subsequently. For obtaining TfNC⊃siRNA, a macromonomer (AzGu) bearing multiple guanidinium (Gu+) ion units, azide (N3) groups, and trityl (Trt)-protected thiol groups in the main chain, side chains, and termini, respectively, was newly designed. Because of a multivalent Gu+-phosphate salt-bridge interaction, AzGu can adhere to siRNA along its strand. When I2 was added to a preincubated mixture of AzGu and siRNA, oxidative polymerization of AzGu took place along the siRNA strand, affording AzNC⊃siRNA, the smallest siRNA-containing reactive nanocaplet so far reported. This conjugate was converted into Glue/BPNC⊃siRNA by the click reaction with a Gu+-appended bioadhesive dendron (Glue) followed by a benzophenone derivative (BP). Then, Tf was covalently immobilized onto Glue/BPNC⊃siRNA by Gu+-mediated adhesion followed by photochemical reaction with BP. With the help of Tf-induced transcytosis, TfNC⊃siRNA permeated deeply into a cancer spheroid, a 3D tissue model, at a depth of up to nearly 70 μm, unprecedentedly.

Mating disks and rods into an ordered phase Disk-shaped molecules tend to stack in columns, whereas rod-shaped ones tend to align parallel to each other. When the two types of molecules are mixed, they tend to phase separate. Yano et al. found the right recipe that allowed enough affinity between the disks and rods so that they formed a blended twisted columnar phase. The phase could be stabilized by polymerizing the disks. The orientation of the twisted columns could be altered using electric fields, whereas optical stimuli could lead to a second ordering transition. Science , this issue p. 161

What particular mechanical properties can be expected for materials composed of interlocked backbones has been a long-standing issue in materials science since the first reports on polycatenane and polyrotaxane in the 1970s

Solvent-free chemical manufacturing is one of the awaited technologies for addressing an emergent issue of environmental pollution. Here, we report solvent-free autocatalytic supramolecular polymerization (SF-ASP), which provides an inhibition-free template-assisted catalytic organic transformation that takes great advantage of the fact that the product (template) undergoes a termination-free nucleation–elongation assembly (living supramolecular polymerization) under solvent-free conditions. SF-ASP allows for reductive cyclotetramerization of hydrogen-bonding phthalonitriles into the corresponding phthalocyanines in exceptionally high yields (>80%). SF-ASP requires the growing polymer to form hexagonally packed crystalline fibres, which possibly preorganize the phthalonitriles at their cross-sectional edges for their efficient transformation. With metal oleates, SF-ASP produces single-crystalline fibres of metallophthalocyanines again in exceptionally high yields, which grow in both directions without terminal coupling until the phthalonitrile precursors are completely consumed. By taking advantage of this living nature of polymerization, multistep SF-ASP without/with metal oleates allows for the precision synthesis of multi-block supramolecular copolymers. The solvent-free conversion of phthalonitrile derivatives into phthalocyanines in the bulk is described, involving a reductive cyclotetramerization step and the formation of one-dimensional single-crystalline fibres. This solvent-free autocatalytic supramolecular polymerization may enable for a sustainable fabrication of multi-block supramolecular copolymers.

Novel liquid crystalline (LC) molecules were prepared from a dimeric porphyrin tape. A series of metal complexes (1Zn, 1Pd, 1Cu, and 1Ni) and the free-base form (12H) of the porphyrin tape formed a columnar LC phase. Although only the central metal ions were different among these compounds, 1Ni, 12H, and 1Cu aligned homeotropically in a sandwiched glass cell, while 1Zn and 1Pd exhibited a random orientation at a macroscopic scale. The strength of the π-π interactions, tunable by the distortion of the porphyrin cores through metallation, is a key factor for the observed macroscopic orientation difference.

A photochemically crushable and regenerative metal–organic framework (DTEMOF) was developed by complexation of photochromic ligand PyDTEopen and 5-nitroisophthalate (nip2–) with Cd2+ in DMF/MeOH. D...

Herein we report the synthesis and isolation of a shape-persistent Janus protein nanoparticle derived from the biomolecular machine chaperonin GroEL (^AGroEL^B) and its application to DNA-mediated ternary supramolecular copolymerization. To synthesize ^AGroEL^B with two different DNA strands A and B at its opposite apical domains, we utilized the unique biological property of GroEL, i.e., Mg²⁺/ATP-mediated ring exchange between ^AGroEL^A and ^BGroEL^B with their hollow cylindrical double-decker architectures. This exchange event was reported more than 24 years ago but has never been utilized for molecular engineering of GroEL. We leveraged DNA nanotechnology to purely isolate Janus ^AGroEL^B and succeeded in its precision ternary supramolecular copolymerization with two DNA comonomers, A** and B*, that are partially complementary to A and B in ^AGroEL^B, respectively, and programmed to self-dimerize on the other side. Transmission electron microscopy allowed us to confirm the formation of the expected dual-periodic copolymer sequence −(^(B*/B)GroEL^(A/A**/A**/A)GroEL^(B/B*))– in the form of a laterally connected lamellar assembly rather than a single-chain copolymer.

The research field of supramolecular polymerization has dramatically progressed in the last three decades, and much deeper insights into its new mechanisms, including kinetic and thermodynamic aspects, have become available. Furthermore, a much wider variety of noncovalent interactions have been exploited for connecting monomers, and the importance of multivalency and the concept of pathway complexity have also been recognized. To control supramolecular polymerization, chain-growth supramolecular polymerization, seeded supramolecular polymerization, and sequence-specific supramolecular copolymerization, which are essential for precise macromolecular synthesis, are now possible. The stereochemical aspects of supramolecular polymerization using chiral monomers have also been studied extensively, contributing to the understanding of the kinetic aspects of supramolecular polymerization. Nanotubular supramolecular polymerization, forming rolled-up 2D architectures, in contrast to linear supramolecular polymerization, has also been developed. Through the conceptual expansion of supramolecular polymerization, a much wider variety of monomers and media have become usable, which will enable many groundbreaking applications that cannot be attained by conventional covalent polymerization.

Caspase-3 (Casp-3) is an enzyme that efficiently induces apoptosis, a form of programmed cell death. We report a dendritic molecular glue PCGlue that enables intracellular delivery of Casp-3 and its photoactivation. PCGlue carrying multiple guanidinium (Gu+) ion pendants via photocleavable linkages can tightly adhere to Casp-3 and deliver it into the cytoplasm mainly by direct penetration through the plasma membrane. Casp-3, whose surface is covered by PCGlue, is unable to interact with its cellular substrates and can therefore not induce apoptosis. However, upon exposure to UV or two-photon near-infrared (NIR) light, PCGlue is cleaved off to liberate Casp-3, triggering the apoptotic signaling cascade. This intracellular photoactivation of Casp-3 allows spatiotemporal induction of apoptosis in irradiated cells.

Brilliance usually refers to the light reflected by the facets of a gemstone such as diamond due to its high refractive index. Nowadays, high-refractive-index materials find application in many optical and photonic devices and are mostly of inorganic nature. However, these materials are usually obtained by toxic or expensive production processes. Herein, the synthesis of a thin-film organic semiconductor, namely, polymeric carbon nitride, by thermal chemical vapor deposition is presented. Among polymers, this organic material combines the highest intrinsic refractive index reported so far with high transparency in the visible spectrum, even reaching the range of diamond. Eventually, the herein presented deposition of high quality thin films and their optical characteristics open the way for numerous new applications and devices in optics, photonics, and beyond based on organic materials.