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Slide-ring polymers exhibit distinctive mechanical properties, making them highly promising for applications in emerging fields such as energy storage devices and smart sensing. However, existing slide-ring polymer systems primarily rely on hydrophilic-hydrophobic interactions to achieve ring-axle interlocking in aqueous phases. This reliance limits the construction of slide-ring networks mainly to water-soluble polymers, excluding a diverse range of lipophilic polymers. Therefore, it is crucial to introduce efficient construction strategies that facilitate interpenetration in organic solvents, enabling the development of diverse slide-ring polymers and expanding their range and applications. Herein, by utilizing the pillar[5]arene/alkyl chain host-guest interactions, we successfully facilitated the interpenetration of a pillar[5]arene and poly(caprolactone), enabling the efficient construction of two slide-ring polymer networks in organic solvents. One of these two slide-ring polymers demonstrates a unique network deformation mechanism along with outstanding mechanical properties compared with the control covalently cross-linked polymer network, including maximum stress (4.43 vs 1.98 MPa), maximum strain (1285 vs 330 %), and toughness (35.4 vs 3.92 MJ/m 3 ). More importantly, this strategy of making slide-ring polymers is highly versatile, given the wide range of macrocyclic arenes and alkyl chain-containing polymers it can accommodate., (© 2024 Wiley-VCH GmbH.)

Vitrimers offer a unique combination of mechanical performance, reprocessability, and recyclability that makes them highly promising for a wide range of applications. However, achieving dynamic behavior in vitrimeric materials at their intended usage temperatures, thus combining reprocessability with adaptivity through associative dynamic covalent bonds, represents an attractive but formidable objective. Herein, we couple boron-nitrogen (B-N) dative bonds and B-O covalent bonds to generate a new class of vitrimers, boron-nitrogen vitrimers (BNVs), to endow them with dynamic features at usage temperatures. Compared with boron-ester vitrimers (BEVs) without B-N dative bonds, the BNVs with B-N dative bonds showcase enhanced mechanical performance. The excellent mechanical properties come from the synergistic effect of the dative B-N supramolecular polymer and covalent boron-ester networks. Moreover, benefiting from the associative exchange of B-O dynamic covalent bonds above their topological freezing temperature (T v ), the resultant BNVs also possess the processability. This study leveraged the structural characteristics of a boron-based vitrimer to achieve material reinforcement and toughness enhancement, simultaneously providing novel design concepts for the construction of new vitrimeric materials., (© 2024 Wiley-VCH GmbH.)

Simultaneously introducing covalent and supramolecular cross-links into one system to construct dually cross-linked networks, has been proved an effective approach to prepare high-performance materials. However, so far, features and advantages of dually cross-linked networks compared with those possessing individual covalent or supramolecular cross-linking points are rarely investigated. Herein, on the basis of comparison between supramolecular polymer network (SPN), covalent polymer network (CPN) and dually cross-linked polymer network (DPN), we reveal that the dual cross-linking strategy can endow the DPN with integrated advantages of CPN and SPN. Benefiting from the energy dissipative ability along with the dissociation of host-guest complexes, the DPN shows excellent toughness and ductility similar to the SPN. Meanwhile, the elasticity of covalent cross-links in the DPN could rise the structural stability to a level comparable to the CPN, exhibiting quick deformation recovery capacity. Moreover, the DPN has the strongest breaking stress and puncture resistance among the three, proving the unique property advantages of dual cross-linking method. These findings gained from our study further deepen the understanding of dynamic polymeric networks and facilitate the preparation of high-performance elastomeric materials., (© 2023 Wiley-VCH GmbH.)

Solar-driven CO 2 reduction reaction (CO 2 RR) is largely constrained by the sluggish mass transfer and fast combination of photogenerated charge carriers. Herein, we find that the photocatalytic CO 2 RR efficiency at the abundant gas-liquid interface provided by microdroplets is two orders of magnitude higher than that of the corresponding bulk phase reaction. Even in the absence of sacrificial agents, the production rates of HCOOH over WO 3  ⋅ 0.33H 2 O mediated by microdroplets reaches 2536 μmol h -1  g -1 (vs. 13 μmol h -1  g -1 in bulk phase), which is significantly superior to the previously reported photocatalytic CO 2 RR in bulk phase reaction condition. Beyond the efficient delivery of CO 2 to photocatalyst surfaces within microdroplets, we reveal that the strong electric field at the gas-liquid interface of microdroplets essentially promotes the separation of photogenerated electron-hole pairs. This study provides a deep understanding of ultrafast reaction kinetics promoted by the gas-liquid interface of microdroplets and a novel way of addressing the low efficiency of photocatalytic CO 2 reduction to fuel., (© 2023 Wiley-VCH GmbH.)

The stability of cationic functional groups is one of the key factors determining lifetime of alkaline anion-exchange membranes (AAEMs) and the AAEM-based electrochemical devices. Main-group metal and crown ether complexes are stable cations due to the absence of degradation pathways including nucleophilic substitution, Hofmann elimination, and cation redox. However, the binding strength, a key feature for AAEM applications, is overlooked in previous work. We herein propose the use of barium [2.2.2]cryptate ([Cryp-Ba] 2+ ) as a new cationic functional group for AAEMs due to its extremely strong binding (10 9.5  M -1 in water at 25 °C). The [Cryp-Ba] 2+ -AAEMs with polyolefin backbones remain stable after treatment in 15 M KOH at 60 °C for over 1500 hours. More importantly, these AAEMs are successfully applied in water electrolyzers, and an anolyte-feeding switch method is designed to further reveal the influence of binding constants., (© 2023 Wiley-VCH GmbH.)

An orthogonal combination of cationic and radical RAFT polymerizations is used to synthesize bottlebrush polymers using two distinct RAFT agents. Selective consumption of the first RAFT agent is used to control the cationic RAFT polymerization of a vinyl ether monomer bearing a secondary dormant RAFT agent, which subsequently allows side-chain polymers to be grafted from the pendant RAFT agent by a radical-mediated RAFT polymerization of a different monomer, thus completing the synthesis of bottlebrush polymers. The high efficiency and selectivity of the cationic and radical RAFT polymerizations allow both polymerizations to be conducted in one-pot tandem without intermediate purification., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis of hydrophilic lanthanide-doped nanocrystals (Ln 3+ -NCs) with molecular recognition ability for bioimaging currently remains a challenge. Herein, we present an effective strategy to circumvent this bottleneck by encapsulating Ln 3+ -NCs in graphene oxide (NCs@GO). Monodisperse NCs@GO was prepared by optimizing GO size and core-shell structure of NaYF 4 :Yb,Er@NaYF 4 , thus combining the intense visible/near-infrared II (NIR-II) luminescence of NCs and the unique surface properties and biomedical functions of GO. Such nanostructures not only feature broad solvent dispersibility, efficient cell uptake, and excellent biocompatibility but also enable further modifications with various agents such as DNA, proteins, or nanoparticles without tedious procedures. Moreover, we demonstrate in proof-of-concept experiments that NCs@GO can realize simultaneous intracellular tracking and microRNA-21 visualization, as well as highly sensitive in vivo tumor-targeted NIR-II imaging at 1525 nm., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The detection of circulating tumor cells (CTCs) is crucial to early cancer diagnosis and the evaluation of cancer metastasis. However, it remains challenging due to the scarcity of CTCs in the blood. Herein, we report an ultrasensitive platform for the direct detection of CTCs using luminescent lanthanide nanoprobes. These were designed to recognize the epithelial cell adhesion molecules on cancer cells, allowing signal amplification through dissolution-enhanced time-resolved photoluminescence (TRPL) and the elimination of short-lived autofluorescence interference. This enabled the direct detection of blood breast-cancer cells with a limit of detection down to 1 cell/well of a 96-well plate. Moreover, blood CTCs (≥10 cells mL -1 ) can be detected in cancer patients with a detection rate of 93.9 % (14/15 patients). We envision that this ultrasensitive detection platform with excellent practicality may provide an effective strategy for early cancer diagnosis and prognosis evaluation., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Sirtuins are protein deacylases regulating metabolism and stress responses, and are implicated in aging-related diseases. Small molecule activators for the human sirtuins Sirt1-7 are sought as chemical tools and potential therapeutics, such as for cancer. Activators are available for Sirt1 and exploit its unique N-terminus, whereas drug-like activators for Sirt2-7 are lacking. We synthesized and screened pyrrolo[1,2-a]quinoxaline derivatives, yielding the first synthetic Sirt6 activators. Biochemical assays show direct, substrate-independent compound binding to the Sirt6 catalytic core and potent activation of Sirt6-dependent deacetylation of peptide substrates and complete nucleosomes. Crystal structures of Sirt6/activator complexes reveal that the compounds bind to a Sirt6-specific acyl channel pocket and identify key interactions. Our results establish potent Sirt6 activation with small molecules and provide a structural basis for further development of Sirt6 activators as tools and therapeutics., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Copper-catalyzed Suzuki–Miyaura-type cross-coupling and carboboration processes are reported. The cross-couplings function well with a variety of substituted aryl iodides and aryl boronic esters and allows for orthogonal reactivity compared to palladium-catalyzed processes. The carboboration method includes both alkynes and allenes and provides access to highly substituted and stereodefined vinyl boronic esters. The alkyne carboboration method is highlighted in the simple one-pot synthesis of Tamoxifen.