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In this work, a series of cationic luminogens (designated as PSMP isomers) were developed based on the cyano positional isomerism strategy. The isomerism of the cyano substituent on the molecular skeleton can finely regulate the optical behaviour, the type of photoinduced reactive oxygen species (ROS), and mitochondria-targeted capability of isomers. Interestingly, PSMP-4, with the cyano group installed at an appropriate location, exhibits a special aggregation-induced emission effect and potent O 2 ˙ - generation efficacy through the type I photochemistry pathway. Notably, PSMP-4 can accumulate in mitochondria with high specificity. Taking advantage of its excellent photostability, PSMP-4 realizes in situ mitochondria imaging in a washing-free manner and sensitive response to the change of mitochondrial membrane potential. The integration of comprehensive photophysical properties and mitochondrial specificity enable PSMP-4 to successfully trigger the death of cancer cells through an efficient type I photodynamic therapy process both in vitro and in multicellular tumor spheroid models.

Previous studies have suggested that diabetic patients should align their food and nutrient intake with their biological metabolic rhythm. However, the optimal timing of coffee consumption to prevent the development of chronic kidney disease (CKD) in diabetic patients remains unknown. This study aims to examine the association between the amount and timing of coffee consumption and CKD prevalence in diabetic patients. We recruited a nationally representative sample of 8564 diabetes patients from NHANES (National Health and Nutrition Examination Survey) from 2003 to 2018. Coffee intake was assessed using a 24 hour dietary recall and categorized into different time periods throughout the day: dawn-to-forenoon (5:00 a.m. to 8:00 a.m.), forenoon-to-noon (8:00 a.m. to 12:00 p.m.), noon-to-evening (12:00 p.m. to 6:00 p.m.), and evening-to-dawn (6:00 p.m. to 5:00 a.m.). Logistic regression models were used to assess the association between the amount and timing of coffee consumption and the prevalence of CKD in diabetic patients. After adjusting for potential confounders, diabetic patients who had the status of coffee consumption throughout the day had a lower prevalence of CKD compared to those who did not (OR: 0.89, 95% CI: 0.80-0.99). In terms of the timing of coffee consumption, diabetic patients who consumed coffee or had higher levels of coffee consumption from dawn-to-forenoon had a lower incidence risk of CKD (OR: 0.87, 95% CI: 0.77-0.98; OR: 0.83, 95% CI: 0.70-0.98). Conversely, diabetic patients who consumed higher levels of coffee during the noon-to-evening and evening-to-dawn periods had an increased incidence risk of CKD (OR: 1.35, 95% CI: 1.07-1.71 and OR: 1.28, 95% CI: 1.01-1.64, respectively). These observations remained robust across different participant subtypes. Our results indicated that diabetic patients who consumed coffee from dawn-to-forenoon had a lower risk of developing CKD, while those who consumed coffee from noon-to-evening or evening-to-dawn had an increased risk.

The practical application of lithium metal batteries (LMBs) is inevitably associated with serious safety risks due to the uncontrolled growth of lithium dendrites. Thus, to inhibit the formation of lithium dendrites, many researchers have focused on constructing three-dimensional porous current collectors with a high specific surface area. However, the homogeneous structure of porous collectors does not effectively guide the deposition of lithium metal to the bottom, leading to a phenomenon known as "top-growth." Recently, the construction of 3D porous current collectors with a lithiophilic gradient has been widely reported and regarded as an effective approach to inhibit lithium top-growth, thus improving battery safety. In this review, we summarize the latest research progress on such anode current collector design strategies, including surface modification of different base materials, design of gradient structures, and field factors, emphasizing their lithium-affinity mechanism and the advantages and disadvantages of different collector designs. Finally, we provide a perspective on the future research directions and applications of gradient affinity current collectors.

The synthesis of specific artificial nanochannels remains a formidable challenge in the field of nanomaterials and synthetic chemistry. In particular, the preparation of artificial nanochannels using amphiphilic graft cyclic-brush copolymers (AGCCs) as monomers has garnered substantial attention. Nevertheless, because of the constrained time and length scales inherent in traditional molecular dynamics simulations, a comprehensive theoretical understanding of the morphological regulation mechanism governing the self-assembly of AGCCs into nanochannels remains elusive. In this study, we employed the dissipative particle dynamics (DPD) method to explore the self-assembly mechanism considering factors such as the DPD interaction parameters, concentrations, and sizes of AGCCs. By calculating the phase diagrams, we predicted the emergence of four distinct nanochannel types: short independent, long independent, parallel, and disordered channels. Importantly, the formation of these nanochannels is highly contingent on specific environmental conditions. Furthermore, we extensively discussed self-assembly processes that lead to different types of nanochannels. The self-assembly of AGCCs is revealed as a multistep process primarily influenced by the interaction parameters. However, while the monomer size and concentration do not introduce novel self-assembly morphologies, they do influence the final aggregation state. The elucidation of the self-assembly mechanism presented in this study deepens our understanding of AGCC nanochannel formation. Consequently, this is a valuable guide for the preparation of copolymer materials with specific functionalities, offering insights into targeted copolymer material design.

Polymer translocation is a fundamental topic in non-equilibrium physics and is crucially important to many biological processes in life. In the present work, we adopt two-dimensional Langevin dynamics simulations to study the forced and spontaneous translocation dynamics of an active filament. The influence of polymer stiffness on the underlying dynamics is explicitly analyzed. For the forced translocation, the results show a robust stiffness-induced inhibition, and the translocation time exhibits a dual-exponent scaling relationship with the bending modulus. Tension propagation (TP) is also examined, where we find prominent modifications in terms of both activity and stiffness. For spontaneous translocation into a pure solvent, the translocation time is almost independent of the polymer stiffness. However, when the polymer is translocated into a porous medium, an intriguing non-monotonic alteration of translocation time with increasing chain stiffness is demonstrated. The semiflexible chain is beneficial for translocation while the rigid chain is not conducive. Stiffness regulation on the diffusion dynamics of the polymer in porous media shows a consistent scenario. The interplay of activity, stiffness, and porous crowding provides a new mechanism for understanding the non-trivial translocation dynamics of an active filament in complex environments.

The presence of sulfamethoxazole (SMX) in natural waters has become a significant concern recently because of its detrimental effects on human health and the ecological environment. To address this issue, it is of utmost urgency to develop a reliable method that can determine SMX at ultra-low levels. In our research, we utilized PVP-induced shape control of a hydrothermal synthesis method to fabricate layer-like structured VS 2 , and employed it as an electrode modification material to prepare an electrochemical sensor for the sensitive determination of SMX. Thus, our prepared VS 2 electrodes exhibited a linear range of 0.06-10.0 μM and a limit of detection (LOD) as low as 47.0 nM (S/N = 3) towards SMX detection. Additionally, the electrochemical sensor presented good agreement with the HPLC method, and afforded perfect recovery results (97.4-106.8%) in the practical analysis. The results validated the detection accuracy of VS 2 electrodes, and demonstrated their successful applicability toward the sensitive determination of SMX in natural waters. In conclusion, this research provides a promising approach for the development of electrochemical sensors based on VS 2 composite materials.

Phenolic compounds are toxic chemical pollutants present in water. Three-dimensional fluorescence spectroscopy analysis is an effective and rapid method for real-time phenol monitoring in aquatic environments. However, similar chemical structures of phenols result in highly overlapping three-dimensional fluorescence spectra. Therefore, it is extremely difficult to analyze and quantify the concentration of components in a mixture system that includes two or more phenolic compounds. In this article, we study the mixed phenol system containing phenol, o -cresol, p -cresol, m -cresol, catechol, and resorcinol combined with excitation-emission matrix (EEM) fluorescence data. A multivariate statistical method called best linear unbiased prediction (BLUP) is proposed to analyze the spectra with the aim to achieve quantitative results and a trilinear decomposition algorithm called parallel factor analysis (PARAFAC) was used for comparison. Two experiments with different calibration samples were set to validate the effectiveness of BLUP through recovery, ARecovery (Average Recovery), AREP (Average Relative Error of Prediction), and RMSE (Root Mean Square Error). Overall, the average recovery of each component in experiment 1 and experiment 2 ranged from 95.91% to 111.62% and 82.91% to 129.02%, respectively. Based on the results of the experiments, the concentration of phenolic compounds in water can be quantitatively determined by combining three-dimensional fluorescence spectroscopy with the BLUP method., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Changing the composition is an important way to regulate the electrocatalytic performance of the oxygen evolution reaction (OER) for metallic compounds. Clarifying the synergistic mechanism among different compositions is a key scientific problem to be solved urgently. Here, based on first-principles calculations, a Ni-O-Fe multisite dynamic synergistic reaction mechanism (MDSM) for the OER of Fe-doped NiOOH (NiFeOOH) has been discovered. Based on the MDSM, Fe/O/Ni are triggered as the active sites in turn, resulting in an overpotential of 0.33 V. The factors affecting the deprotonation, O-O coupling, and O 2 desorption during the OER process are analyzed. The electron channels related to the magnetic states among Fe-O-Ni is revealed, which results in the decoupling between OER sites and the oxidation reaction sites. O-O coupling and O 2 desorption are affected by ferromagnetic coupling and the instability of the lattice O during the OER process, respectively. The results give a comprehensive understanding of the active sites in NiFeOOH and provide a new perspective on the synergistic effects among different compositions in metal compounds during the OER process.

Efficient synergistic therapeutic strategies for tumors with high specificity and sensitivity remain a major challenge. An injectable near-infrared (NIR)-responsive supramolecular hydrogel was prepared via host-guest interactions between conjugated poly( N -phenylglycine)-poly(ethylene glycol) (PNPG-PEG) and α-cyclodextrin. A reactive oxygen species (ROS)-triggered chain-breakage prodrug was composed of a thioketal (TK) linkage of methoxy poly(ethylene glycol) (mPEG) and doxorubicin (DOX). The resulting amphiphilic conjugate mPEG-TK-DOX can self-assemble into prodrug micelles. PEG/poly(etherimide) (PEI)@Fe 3 O 4 nanoparticles (PEG/PEI@Fe 3 O 4 NPs) were prepared using a thermal decomposition method. The prodrug micelles and PEG/PEI@Fe 3 O 4 NPs can be well dispersed into the hydrogel system. In a tumor micro-acid environment, PEG/PEI@Fe 3 O 4 NPs catalyze the decomposition of H 2 O 2 to highly toxic ˙OH via a Fenton reaction to induce the breakage of ROS-responsive TK bonds for the dissociation of micelles and the continuous release of DOX. PEG/PEI@Fe 3 O 4 NPs can also generate an NIR-thermal effect and enhance the photothermal therapy. Notably, by combining with controllable photothermal therapy, the in situ composite hydrogel system shows enhanced synergistic chemo-photothermal therapy for tumors and almost complete in vitro and in vivo tumor suppression, providing a promising synergistic tumor treatment strategy.

Natural polymers have been particularly appealing for constructing hemostatic materials/devices, but it is still desirable to develop new natural polymer-based biomaterials with balanced hemostatic and wound-healing performance. In this work, a natural polyphenol-functionalized chitosan/gelatin sponge (PCGS) was prepared by the lyophilization of a chitosan/gelatin mixture solution (under a self-foaming condition to prepare the CGS) and subsequent chemical cross-linking with procyanidin (PC). Compared with the original CGS, PCGS exhibited an enhanced liquid-absorption ability, reduced surface charges, and similar/low hemolysis rate. Benefiting from such a liquid-absorption ability (∼4000% for whole blood and normal saline) and moderate surface charges, PCGS exhibited high in vitro hemostatic property and promising hemostatic performance in an in vivo femoral-artery-injury model. In addition, PCGS possessed higher antioxidant property and slightly decreased antibacterial ability than CGS, owing to the incorporation of PC. The feasibility of PCGS for treating infected wounds was further confirmed in an in vivo infected-tooth-extraction model, as the typical complication of intractable tooth-extraction bleeding. The present work demonstrated a facile approach for developing multifunctional hemostatic materials through the flexible management of natural polymers and polyphenols.

Ankaflavin (AK) is a typical yellow pigment extracted from Monascus -fermented rice with several biological effects; however, its solubility is poor. Thus, research studies of the delivery systems of AK, especially those constructed from protein-polysaccharide complexes, have attracted considerable attention. However, the interactions that exist in the system have rarely been investigated. This work focused on the interactions between AK and bovine serum albumin (BSA) as well as the influence of carrageenan (Car) on the binding of AK to BSA. Results revealed that the quenching of BSA by AK involved the static quenching mechanism. The formed BSA-AK complexes were mainly maintained by hydrophobic forces and AK was located within the hydrophobic cavity of BSA. Compared to free AK or AK only complexed with BSA, a higher absorption intensity of AK was observed for the formed BSA-AK-Car complexes, indicating changes in the microenvironment of AK. This was confirmed by the increase in the α-helix content of BSA after the formation of BSA-AK-Car complexes. Hydrogen bond, van der Waals, and electrostatic interactions were verified to be the primary forces preserving the BSA-AK-Car complexes. Moreover, the antioxidant potential of Monascus -fermented products rich in AK (denoted as Mps), namely BSA-Mps and BSA-Mps-Car was evaluated. The antioxidant activity of Mps was negatively impacted by BSA, while the addition of Car could enhance the antioxidant capacity of BSA-Mps-Car complexes. Meanwhile, Mps showed a protective effect against free radical-induced oxidation damage to BSA, and Car could further improve this effect.

Extensive studies so far have indicated that chirality, anisotropic interactions and spatial confinement play important roles in collective dynamics in active matter systems. However, how the overall interplay of these crucial factors affects the novel phases and macroscopic properties remains less explored. Here, using Langevin dynamics simulations, we investigate the self-organization of a chiral active system composed of amphiphilic Janus particles, where the embedded anisotropic interaction orientation is assumed to be either the same or just opposite to the direction of active force. A wealth of dynamic phases are observed including formation of phase separation, clustering state, homogeneous state, spiral vortex flow, swarm and spatiotemporal oscillation. By tuning self-propelled angular speed and anisotropic interaction strength, we identify the non-equilibrium phase diagrams, and reveal the very non-trivial modulation of both vortex and swarm patterns. Intriguingly, we find that strong chirality-alignment-confinement coupling yields a self-driven spatial and temporal organization periodically oscillating between a counterclockwise vortex and a clockwise one. Our work provides a new understanding of the novel self-assembly arising in such a confined system and enables new strategies for achieving ordered dynamic structures.

Herein, we report a facile approach for the preparation of two-dimensional iodine nanosheets (2D iodine NSs) with good stability and high biocompatibility via an aqueous solvent-assisted ultrasonic route. Due to the large specific surface area of the 2D morphology, iodine NSs effectively interact with bacterial membranes and destroy bacterial integrity, as well as further damaging intracellular DNA, showing prominent antibacterial activity against S. aureus in vitro and in vivo .

This paper proposed a novel spectrometric quantification method for nitrate and COD concentration in water using a double-channel 1-D convolution neural network for relatively long UV-vis absorption spectra data (2600 points). To improve the model's ability to resist turbidity disturbance, a new dataset augmentation method was applied and the absorption spectra of nitrate and COD under different turbidity disturbances were successfully simulated. Compared to the PLSR model, the value of RRMSEP for the CNN model was reduced from 6.1% to 1.4% in nitrate solution and 4.5% to 1.3% in COD solution. Compared to the PLSR model, the regression accuracy of the CNN model was increased from 56% to 93% in nitrate solution and 68% to 91% in COD solution. The test on the actual solution under different turbidity disturbances shows that the 1D-CNN model had a bias rate of less than 2% in both nitrate and COD solutions, while the worst bias rate in the PLSR method was 15%., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Inflammatory bowel disease (IBD) is a multifaceted and recurrent immune disorder that occurs in the gastrointestinal tract. Betaine is a natural compound that exerts beneficial anti-inflammatory effects. However, the role of betaine in protecting IBD is still unclear. Therefore, the aim of our study was to investigate the anti-inflammatory effect of betaine in dextran sulfate sodium (DSS)-induced colitis. The results showed that betaine greatly increased the body weight and decreased the disease activity index score of DSS-treated mice. Furthermore, betaine effectively downregulated the protein levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNFα) and upregulated tight junction proteins (occludin and ZO-1) in the mice. Additionally, betaine exposure remarkably restricted the DSS-induced phosphorylation of IκB and NF-κB p65 in mice. Similarly, betaine pretreatment improved the inflammatory response and intestinal barrier of Caco-2 cells. Betaine altered the gut microbiota composition, markedly decreasing the relative abundance of Firmicutes and Proteobacteria and considerably increasing the relative abundance of Bacteroidota and Campylobacterota in DSS-induced mice. In conclusion, betaine could attenuate colitis via regulating the inflammatory response, enhancing the intestinal barrier, and altering gut microbiota and is conducive to developing new drugs for treating human diseases.

Hydrogels are becoming increasingly popular in biomedical and soft machine manufacturing, but their practical application is limited by poor mechanical properties. In recent years, Hofmeister effect-enhanced gelatin hydrogels have become popular. However, the synergy of the Hofmeister effect using other toughening methods is still less investigated. We have fabricated an ultra-high strength gelatin-based hydrogel by introducing ligand cross-linking and hydrogen bonds. Unlike conventional double-network hydrogels, the dense physical cross-linking involving sacrificial bonds gives the hydrogel excellent fatigue resistance and self-recovery properties. The enhancement of mechanical properties by the Hofmeister effect is attributed to the disruption of the hydration shell of the gelatin molecular chains, which leads to stronger interactions between the molecular chains. The mechanical properties of the hydrogels are adjustable over a wide range by varying the concentration of the soaked (NH 4 ) 2 SO 4 solution. The fixation of the gelatin molecular chain orientation by the Hofmeister effect and the reorganization of the coordination bonds allow the hydrogels to be self-reinforced by pre-stretching. At the same time, the modulus contraction of hydrogels in high-concentration salt solutions, and relaxation and swelling in dilute solutions exhibit ionic stimulation responses and shape recovery capability, and hybrid hydrogels have great potential as bio-actuators.

The design of responsive materials by introducing dynamic covalent bonds (DCBs), which can undergo reversible association and dissociation under certain conditions, is an appealing research field in recent years. Reversible isocyanate chemistry representatively consists of urethane, thiourethane, and urea bonds, all of which can reverse into their own starting chemicals (isocyanates and active hydrogen compounds) upon heating. In this article, we overview the mechanisms and experimental elements affecting the dynamic features of isocyanate-based bonds (IBs). With the knowledge of reversible isocyanate chemistry, the construction strategies of different dynamic covalent polymers including polyurethanes, polyureas, and polythiourethanes are discussed, in particular for dynamic polymer networks. The major applications of dynamic isocyanate-based polymers in recycling and self-healing materials, shape morphing polymers, 3D printing, and composites are outlined. The emergence of reversible isocyanate chemistry offers a highly effective platform to engineer thermally adaptable materials.

The rGO/CeO 2 /FTO nanocomposite modified electrode was prepared by an electrochemical method. A simple and highly sensitive electrochemical sensing platform for electrochemical rGO and modified CeO 2 nanoribbons directly on FTO electrodes was developed. Simultaneous determination of Pb 2+ and Cd 2+ used the differential pulse anodic stripping voltammetry (DPASV) method. The method was simple to operate, and CeO 2 nanobelts could be obtained simultaneously by electrodeposition and reduction of GO without further processing. This is an environmentally friendly electrochemical method to obtain modified electrodes under mild conditions. The experimental results showed that the linear calibration curves of Pb 2+ and Cd 2+ are 1-300 and 0.2-500 μg L -1 , respectively. At the same time, no interference from other coexisting metal ions was found during the detection process, which proved that the modified electrode had good stability and repeatability., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Over the recent years, intelligent, multi-responsive micelles have received considerable attention due to their promising application in a variety of fields, including biomedical technology, drug delivery, separation, and catalysis. However, the design of such systems with controlled self-assembly is challenging both experimentally and theoretically and is still in the nascent stage. In this study, a novel dual-stimuli triggered wormlike micellar solution is prepared by mixing cationic surfactants 3-hexadecyloxy-2-hydroxypropyltrimethylammonium bromide (R 16 HTAB) and sodium hydrogen phthalate (SHP). The viscoelasticity, aggregate morphology, and pH- and thermo-responsive behavior of the micellar solution are examined by rheological measurements, cryogenic-transmission electron microscopy (cryo-TEM), nuclear magnetic resonance ( 1 H NMR) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. The dual-sensitive fluid can be switched between a water-like state and a gel-like state by adjusting the pH and temperature. The variations in the flowing behavior are ascribed to the microstructural transition between wormlike micelles, short cylindrical micelles, and spherical micelles. Furthermore, based on the experimental results, dual-responsive behavior of the mixed solution is attributed to the different binding modes between SHP and the surfactant with the variation in the pH and temperature. We hope that the proposed system provides a new route for developing multi-stimuli-responsive materials that are capable of adapting to local environmental variations.

The extensive use of traditional cooking stoves to meet daily cooking and heating requirements has highlighted the serious problem of indoor and outdoor air pollution. This study evaluates seven improved coal-fired space-heating and cooking stoves and compares them with a widely used stove of an older design, selected as a baseline reference. The seven stoves were selected from a range of candidate improved stoves submitted by manufacturers for testing as part of the air quality improvement in the Hebei Clean Air Project, Hebei Province, China. Stove performance was evaluated when burning raw coal and coal briquettes during the high and low power stages respectively. All seven improved cooking stoves surpassed the baseline stove in combined heating and cooking thermal and emission performance. Among the improved cooking stoves, Model 2-TL was found to have the highest average thermal efficiency, 87.2 ± 0.5%, when burning coal briquettes at high and low power. The lowest emission of PM 2.5 was 0.94 ± 0.5 mg MJ NET -1 , CO 0.55 ± 0.28 g MJ NET -1 , and CO/CO 2 1.1 ± 0.6%, respectively. It is concluded that the use of these improved heating and cooking stoves should be promoted for daily cooking and heating requirements. This strategy will not only save fuel to the benefit of the household, but widespread adoption could contribute to significant reductions of CO and PM 2.5 emissions in Hebei Province., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The combination of photothermal therapy (PTT) and gene therapy (GT) has attracted intense interest in cancer treatment. However, the lack of long circulation and active tumor targeting reduces the therapeutic efficacy of complementary PTT/GT. In this work, hyaluronic acid (HA)-cloaked gold nanorods-PGED (prepared by ring-opening of polyglycidyl methacrylate (PGMA) with ethylenediamine (ED))/pDNA (AP/pDNA-HA) complexes were prepared to achieve long circulation and tumor targeting for photoacoustic imaging (PAI)-guided synergistic PTT/GT. Gold nanorods endow the complexes with photothermal effect and PAI function. Benefiting from the HA cloak, the AP/pDNA-HA complexes exhibit excellent stability, biocompatibility, long circulation behavior and active targeting. In addition, the pH-responsive characteristic of the Schiff base bonds helps the AP/pDNA-HA complexes to effectively escape from the endosome/lysosome. The antioncogene p53 was employed to investigate the gene transfection efficiency of the delivery system both in vitro and in vivo . The superiority of synergistic PTT/GT is established in a mouse 4T1 breast tumor model. The current study provides a facile strategy for constructing multifunctional gene delivery systems with long circulation and tumor targeting features, which can achieve effective imaging-guided synergistic tumor treatment.

Macromolecular crowding plays a crucial role in determining the dynamics in a living cell. We adopt Langevin dynamics simulations to investigate the anomalous diffusion dynamics of passive and active particles in a solution of polymer chains with tunable stiffness. The solution's anisotropic feature is modulated by changing both the polymer stiffness and volume fraction, where isotropic-to-nematic phase transition is involved. Our results demonstrate the significant impact of polymer flexibility on the dynamics of both passive and active probes. The distinct diffusion mechanism for an active particle is clarified by the interplay between polymer stiffness, crowdedness and activity. Polymer stiffness leads to a global inhibition effect on passive particle diffusion. The diffusion coefficient exhibits an intriguing non-monotonic variation at increasing polymer stiffness, which is due to the fact that the alignment of polymer chains is beneficial for diffusion along the nematic direction but unfavorable for that in the direction perpendicular to it. In sharp contrast, polymer stiffness plays a dominant role in facilitating active particle diffusion. Self-propulsion of the particle can utilize stiffness-induced elastic interactions more efficiently, which promotes its mobility in both directions. Meanwhile, an active particle might have a stronger ability to take advantage of the polymer alignment, contributing substantially enhanced diffusivity. In addition, the diffusion coefficient of an active particle is subject to a tendency of degeneration against varying volume fraction. This counter-intuitive behavior is due to the contrasting factors that increasing crowdedness induces a lower particle speed but a longer persistent motion time.

Liquid crystalline elastomer (LCE) materials have been developed and investigated for several decades. One important obstacle, which impedes the practical industrial application of LCE materials, is their modest robustness as actuator materials. In this work, we developed a LCE composite which was fabricated by incorporating eiderdown fibers into a polysiloxane-based main-chain LCE matrix. The eiderdown fibers were used as the flexible reinforcement phase suitable for the shape-morphing performance of LCE materials upon being stimulated. Due to the long fiber property, specific structure and surface characteristics of the eiderdown fibers, they constructed a reinforcement network in the LCE matrix and formed tight interfacial adhesion with the matrix. The LCE composite demonstrated enhanced actuation mechanical properties and robust actuation performance. Its actuation blocking stress and modulus were increased due to the reinforcement effect of the eiderdown fibers. The tensile strength and the performance of anti -fatigue failure under repeated actuation cycles and high loadings were greatly improved due to the crack-resisting effect and bridging effect of the eiderdown fibers. While other properties, such as the liquid crystalline phase structure, the stimulus deformation ratio, phase transition temperature of the LCE matrix, etc. , did not deteriorate or change due to the high flexibility, thermal stability and chemical stability of the eiderdown fibers.

The brittle fracture of polyurethane elastomer (PUE) under high-speed impact limits its application in high-speed impact protection. Here, based on the principle of free radical polymerization and π-π conjugation, composite nanoparticles (C-MWCNTs) are prepared by copolymerization of epoxy group ionic liquid (GVIMBr) and divinylbenzene (DVB) on MWCNTs using DVB as a linker. C-MWCNTs participate in the curing process of PUE through epoxy groups to form in situ crosslinked C-MWCNTs/PUE, which improves the energy absorption and high-speed impact properties of PUE. Compared with neat PUE, the maximum compressive strength and energy absorbed by C-MWCNTs/PUE are increased by 46.3% and 23.6%, respectively. By observing the microsurface and fracture morphology of C-MWCNTs/PUE, the relationship between macroscopic mechanical properties and microstructure is constructed. The improvement of the mechanical properties of the C-MWCNTs/PUE is attributed to the interfacial interaction and homogeneous dispersion of the C-MWCNTs in the PUE matrix. These microscopic effects are caused by the good compatibility between GVIMBr and PUE matrix and the synergistic enhancement between GVIMBr and MWCNTs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Development of a covalent-organic framework (COF)-based Z-scheme heterostructure is a promising strategy for solar energy driven water splitting, but the construction of a COF-based Z-scheme heterostructure with well-defined architecture, large contact area and intimate contact interfaces is scarce. Herein, we fabricated a direct Z-scheme heterostructure COF-metal sulfide hybrid (T-COF@CdS) with shell-core architecture by self-polymerization of 1,3,5-benzenetricarboxaldehyde and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine in situ on CdS. The formed C-S chemical bonding between T-COF and CdS could provide a very tight and stable interface. Owing to the properly staggered band alignment, strong interfacial interaction and large interfacial contact area between T-COF and CdS, a Z-scheme route for charge separation and transfer is realized, resulting in electron accumulation in CdS for H 2 O reduction. The obtained Z-scheme heterostructure T-COF@CdS-3 exhibits a high apparent quantum efficiency of 37.8% under 365 nm monochromatic light irradiation, and long-term stability arising from shell-core structures in which the T-COF shell protects the catalytic centers of CdS against deactivation, as well as acts as oxidation sites to avoid the photocorrosion of CdS. This work provides a strategy for the construction of a shell-core direct Z-scheme heterostructure photocatalyst for water splitting with high performance., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

A typical biological environment is usually featured by crowding and heterogeneity, leading to complex reaction kinetics of the immersed macromolecules. In the present work, we adopt Langevin dynamics simulations to systematically investigate polymer looping kinetics in active heterogeneous media crowded with a mixture of mobile active particles and immobile obstacles. For comparison, a parallel study is also performed in the passive heterogeneous media. We explicitly analyze the change of looping time and looping probability with the variation of obstacle ratio, volume fraction and crowder size. We reveal the novel phenomena of inhibition-facilitation transition of the looping rate induced by heterogeneity, crowdedness and activity. In addition, our results demonstrate a very non-trivial crowder size effect on the looping kinetics. The underlying mechanism is rationalized by the interplay of polymer diffusion, conformational change and looping free-energy barrier. The competing effect arising from active particles and obstacles on structural and dynamical properties of the polymer yields a consistent scenario for our observations. Lastly, the non-exponential kinetics of the looping process is also analyzed. We find that both activity and crowding can strengthen the heterogeneity degree of the looping kinetics.

A novel dual-emission ratiometric fluorescent probe based on N-doped yellow fluorescent carbon dots (y-CDs) and blue fluorescent copper nanoclusters (CuNCs) was established for quantitative determination of Cu 2+ and biothiols. In this work, the Cu 2+ -(y-CDs) complexes formed by the chelation of y-CDs with Cu 2+ , showed an absorption peak at 430 nm that not only enhanced the fluorescence of y-CDs through inhibiting photoinduced electron transfer (PET) but also effectively quenched the fluorescence of CuNCs due to Förster resonance energy transfer (FRET). In addition, the chelation of y-CDs with Cu 2+ could be inhibited by biothiols that prevented the fluorescence of y-CDs from being enhanced and the fluorescence of CuNCs from being quenched. On account of the changes of ratiometric signal, a dual-emission fluorescence probe for Cu 2+ and biothiols determination was achieved. The proposed method exhibited high sensitivity for Cu 2+ and biothiols in the ranges of 0.5-100 μM and 0.8-50 μM and the limits of detection (LODs) of Cu 2+ , glutathione (GSH), cysteine (Cys) and homocysteine (Hcy) were 0.21 μM, 0.33 μM, 0.39 μM and 0.46 μM, respectively. Subsequently, the established strategy presented an application prospect for the detection of Cu 2+ and biothiols in real samples., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

As one of the most widely used organophosphorus pesticides, chlorpyrifos (CPF) is toxic to humans. However, the rapid, effective and sensitive detection of CPF is still a challenge. In this paper, a novel molecularly imprinted phosphorescent sensor with a core-shell structure (Mn:ZnS QDs@ZIF-8@MIP) using Mn:ZnS quantum dots (QDs) as phosphorescent emitters was prepared for the highly sensitive and selective detection of CPF, and a simple and rapid room-temperature phosphorescence (RTP) detection method for CPF was proposed. For the prepared Mn:ZnS QDs@ZIF-8@MIP, Mn:ZnS QDs had good phosphorescence emission characteristics, ZIF-8 as support materials was used to improve the dispersibility of Mn:ZnS QDs, and molecularly imprinted polymer (MIP) on the surface of ZIF-8 was used to improve the selectivity of Mn:ZnS QDs for CPF. Under the optimal response conditions, the RTP intensity of Mn:ZnS QDs@ZIF-8@MIP showed a rapid response to CPF (less than 5 min), the RTP intensity ratio of P 0 / P had a good linear relationship with the concentration of CPF in the range of 0-80 μM, and the detection limit of this method was 0.89 μM with the correlation coefficient of 0.99. Moreover, this simple and rapid method has been successfully used to detect CPF in real water samples with satisfactory results, and the recoveries ranged from 92% to 105% with a relative standard deviation of less than 1%. This method combines the advantages of phosphorescence emission and molecular imprinting, and greatly reduces the potential interferences of competitive substances, background fluorescence and scattered light, which opens up a broad prospect for the highly sensitive and selective detection of pollutants in water based on molecularly imprinted phosphorescent sensors., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Nanopore detection is a label-free detection method designed to analyze single molecules by comparing specific translocation events with high signal-to-noise ratios. However, it is still challenging to understand the influences of structural flexibility of 100 nm DNA origami on nanopore translocations. Here, we used solid-state nanopores to characterize the translocation of "nunchaku" origami structures, the flexibility of which can be regulated by introducing specific DNA strands and streptavidin protein. The structural changes can result in significant variations in the translocation signals and distributions. It is anticipated that such a method of the flexible DNA origami translocation through a solid-state nanopore will find further applications in molecular detection as well as biosensing., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Due to their ultra-thin morphology, larger specific surface area and more exposed active sites, two-dimensional (2D) metal-organic framework (MOF) nanosheets can break the limitations of three-dimensional (3D) MOFs in sensitivity, response speed and the limit of detection for sensing applications. In this work, fluorescent NH2-MIL-53(Al) nanosheets were developed as a fluoride detection sensor compared with the 3D bulk counterpart. The morphological and structural characteristics of the obtained products were systematically characterized, and the favourable chemical and fluorescence stability of the NH2-MIL-53(Al) nanosheets were explored. The fluorescent NH2-MIL-53(Al) nanosheets showed high sensitivity, fast response speed (as short as 10 seconds), low limit of detection (15.2 ppb), and wide linear detection range (5-250 μM), and all performances were better than those of their bulk counterpart. In addition, the sensing mechanism was investigated to be based on the transformation of the NH2-MIL-53(Al) framework that induced the release of fluorescent ligands, resulting in an exceptionally enhanced fluorescence. This work highlights the advantages of 2D MOF nanosheets in fluorescence sensing applications.

Intra-chain looping in complex environments is significant in advancing our understanding of biological processes in life. We adopt Langevin dynamics simulations to perform a comparative study of polymer looping kinetics in passive and active environments. From the analysis of looping quantities, including looping-unlooping times and looping probabilities, we unraveled the intriguing effects of active crowder size, activity and crowding. Firstly, we figured out the phase diagram involving a novel facilitation-inhibition transition in the parameter space of active crowder size and active force, and the two-fold roles of activity are clarified. In particular, we find that active particles of a size comparable to the polymer monomer are most favorable for facilitated looping, while those with a similar size to the polymer gyration radius impede the looping most seriously. Secondly, the underlying looping mechanisms in different active crowder size regimes are rationalized by the interplay among diffusion, polymer conformational change and the free-energy barrier. For small active crowders, activity significantly promotes end-to-end distance diffusion, which dominantly facilitates both looping and unlooping processes. In the case of moderate active crowders, the polymer chain suffers from prominent swelling, and thus inevitable inhibited looping will occur. For large active crowders, activity induces a counterintuitive non-cage effect on the looping kinetics, through yielding a higher effective temperature and larger unlooping free-energy barrier. This is in sharp contrast to the caging phenomena observed in passive media. Lastly, the volume-fraction dependence of the looping quantities in an active bath demonstrates dramatic discrepancies from that in a passive bath, which highlights the contrasting effects of activity and crowding.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis (UC), is a chronic disease characterized by diffuse mucosal inflammation limited to the colon. Topical drug delivery systems that could be facilely performed and efficiently retained at colon sites are attractive for clinical IBD treatment. Herein, we report the exploration of an injectable thermosensitive copolymer hydrogel as a topical formulation for IBD treatment and demonstrate its feasibility in UC treatment by shielding ulcer sites from the external environment and being a drug reservoir for sustained release. Poly(aliphatic ester)-based triblock copolymer, poly(dl-lactic acid)-poly(ethylene glycol)-poly(dl-lactic acid) (PDLLA-PEG-PDLLA), adopts the solution state at room temperature yet a gel state at body temperature when the polymer concentration is more than 11%. The gel acts not only as a physical mucosal barrier for protecting ulcer sites from microorganisms like bacteria but also as a mesalazine depot for enhanced drug retention in the colon for localized, sustained drug release. In vivo UC treatment reveals that blank gel as a mucosal protector shows nearly the same treatment effect to mesalazine SR granules. Mesalazine-loaded gel significantly suppresses inflammation and has the best outcomes of indices such as colonic length, mucosal injury index, pathological tissue, and inflammatory factor. The injectable thermosensitive polymer hydrogel represents a novel, robust platform for the efficient treatment of IBD by acting as a physical shield to block out the pro-inflammatory factors as well as a drug depot for enhanced drug retention and controlled delivery.

The regenerative repair of large bone defects is a major problem in orthopedics and clinical medicine. The key problem is the lack of ability of existing bone graft materials to promote osteogenesis and angiogenesis. Previous studies have shown that the osteogenic or angiogenic abilities of these materials could be significantly improved by adding miRNA or small-molecule drugs to bone graft materials; however, the synergistic effect arising from this combination is not clear. Therefore, we proposed to construct a dual drug delivery system that could simultaneously achieve the co-encapsulation and co-delivery of miRNA and small-molecule drugs to explore the effect of a dual drug delivery system on bone repair. In this study, we constructed dual-sized pore structure calcium-silicon nanospheres (DPNPs) and achieved the co-encapsulation of miR-210, angiogenic gene drugs, and simvastatin (Siv), a small-molecule osteogenic drug, through metal-ion coordination and physical adsorption. In vitro and in vivo osteogenic and angiogenic experiments showed that the dual drug delivery system (Siv/DPNP/miR-210) exhibited better properties than those of the individual unloaded and single drug-loaded systems and could significantly accelerate the process of bone repair, which provides a novel strategy for the regeneration and repair of bone defects.

Polymer translocation in complex environments is crucially important to many biological processes in life. In the present work, we adopted two-dimensional Langevin dynamics simulations to study the forced and unbiased polymer translocation dynamics in active and crowded media. The translocation time and probability are analyzed in terms of active force F a , volume fraction φ and also the crowder size. The non-trivial active crowder size effect and activity-crowding coupling effect as well as the novel mechanism of unbiased translocation between two active environments with different active particle sizes are clarified. Firstly, for forced translocation, we reveal an intriguing non-monotonic dependence of the translocation time on the crowder size in the case of large activity. In particular, crowders of intermediate size similar to the polymer segment are proven to be the most favorable for translocation. Moreover, a facilitation-inhibition crossover of the translocation time with increasing volume fraction is observed, indicating a crucial activity-crowding coupling effect. Secondly, for unbiased translocation driven by different active crowder sizes, the translocation probability demonstrates a novel turnover phenomenon, implying the appearance of an opposite directional preference as the active force exceeds a critical value. The translocation time in both directions decreases monotonically with the active force. The asymmetric activity effect together with the entropic driving scenario provides a reasonable picture for the peculiar behavior observed in unbiased translocation.

Gut microbiota (GM) is considered to play an important role in obesity. Additionally, the impact of dietary fiber (DF) consumption on GM has been well established. Brown seaweeds are known to be a rich source of DF. However, the effect of insoluble DFs (IDFs) alone from brown seaweed on obesity and GM remains to be determined. This study investigated the effect of IDFs prepared from Laminaria japonica Aresch on high-fat diet (HFD)-induced obesity and GM dysbiosis in mice. Although HFD-induced body weight gain was not significantly attenuated by the IDF treatment, HFD-induced liver injury was ameliorated, and the HFD-elevated serum cholesterol concentration and glucose level of obese mice were significantly lowered. IDF treatment significantly modulated the GM composition disturbed by the HFD. It was found that 5% IDFs restored the GM to a very similar composition to that in the normal mice. The relative abundance of Akkermansia genus was decreased by >300-fold in HFD-fed mice, and it was fully restored by 5% IDF administration. Akkermansia muciniphila, a short-chain fatty acid producer, was identified as a marker species in both control and high-dose IDF groups. Furthermore, IDFs significantly restored the HFD-reduced acetate and propionate levels in the cecal content. In conclusion, the beneficial effect of IDFs derived from L. japonica on obesity was confirmed in mice, and the underlying mechanism may be associated with the modulation of GM composition, possibly through the enrichment of Akkermansia.

It took only 11 years for the power conversion efficiency (PCE) of perovskite solar cells (PSCs) to increase from 3.8% to 25.2%. It is worth noting that, as a new thin-film solar cell technique, defect passivation at the interface is crucial for the PSCs. Decorating and passivating the interface between the perovskite and electron transport layer (ETL) is an effective way to suppress the recombination of carriers at the interface and improve the PCE of the device. In this work, several acceptor-donor-acceptor (A-D-A) type fused-ring organic semiconductors (FROS) with indacenodithiophene (IDT) or indacenodithienothiophene (IDDT) as the bridging donor moiety and 1,3-diethyl-2-thiobarbituric or 1,1-dicyromethylene-3-indanone as the strong electron-withdrawing units, were deposited on the SnO 2 ETL to prepare efficient planar junction PSCs. The PCEs of the PSCs increased from 18.63% for the control device to 19.37%, 19.75%, and 19.32% after modification at the interface by three FROSs. Furthermore, impedance spectroscopy, steady-state and time-resolved photoluminescence spectra elucidated that the interface decorated by FROSs enhance not only the extraction of electrons but also the charge transportation at the interface between the perovskite and ETL. These results can provide significant insights in improving the perovskite/ETL interface and the photovoltaic performance of PSCs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Recently, exploring new luminescent metal-organic frameworks (LMOFs) to selectively detect nitro-aromatic compounds (NACs) has been a hot topic of research. Simultaneously, it is still a challenging issue to understand the sensing mechanism of luminescent MOFs interacting with NACs at the molecular level. In this work, highly fluorescent Sc-tetracarboxylate frameworks (Sc-EBTC) have been successfully synthesized through a solvothermal method. The as-prepared Sc-EBTC crystals have good thermal stability, chemical stability as well as strong fluorescence (λ ex = 320 nm and λ em = 400 nm), and they can detect various NACs rapidly (as short as 30 s), selectively and efficiently by the "turn-off" fluorescence mechanism. The detection limits of Sc-EBTC toward 2,4-DNP and 4-NP are quantified to be 5.71 ppb and 6.26 ppb, respectively. Furthermore, to better understand the sensing mechanism, we attempt to use solid-state NMR and X-ray photoelectron spectroscopy to vividly characterize the charge transfer caused by the interaction between NAC molecules and the MOF at the molecular level. Additionally, test strips were made successfully for the practical detection of the NACs. This study demonstrates that the MOF constructed from the H 4 EBTC ligands might be a promising candidate for the detection of trace NACs.

Identifying drug-target interactions (DTIs) is an important part of drug discovery and development. However, identifying DTIs is a complex process that is time consuming, costly, long, and often inefficient, with a low success rate, especially with wet-experimental methods. Computational methods based on drug repositioning and network pharmacology can effectively overcome these defects. In this paper, we develop a new fusion method, called FPSC-DTI, that fuses feature projection fuzzy classification (FP) and super cluster classification (SC) to predict DTI. As the experimental result, the mean percentile ranking (MPR) that was yielded by FPSC-DTI achieved 0.043, 0.084, 0.072, and 0.146 on enzyme, ion channel (IC), G-protein-coupled receptor (GPCR), and nuclear receptor (NR) datasets, respectively. And the AUC values exceeded 0.969 over all four datasets. Compared with other methods, FPSC-DTI obtained better predictive performance and became more robust.

The synthesis of metal-organic frameworks (MOFs) with a template strategy is still fascinating and has received considerable attention from structural chemists. In this review, developments in tuning MOF hosts or pore structures with a template strategy in the past decades are summarized. By adding templates into MOF precursors, novel template@MOF materials can always be obtained, which cannot be accessed by traditional synthesis procedures. Template@MOF materials can be structurally characterized to help understand the interactions between host frameworks and guest templates. On the other hand, changing the species or amount of template may lead to a pore structure change that can be used as a molecular container to load functional guest molecules with matching sizes for specific applications. It is hoped that this review will provide future researchers with new insight into the design and synthesis of MOF materials by applying suitable templates.

We report four-coordinate nickel(ii)-methyl complexes of tris-carbene borate ligands which adopt rare seesaw geometries. Experimental and computational results suggest the structural distortion from threefold symmetry results from a combination of electronic stabilization of the singlet state, strong field donors, and constrained angles from the chelating ligand.

We adopt a Langevin-dynamics based simulation to systematically study the conformational change of a semi-flexible probed polymer in a rod crowding environment. Two topologically different probed polymer types, linear and ring polymers, are specifically considered. Our results unravel the significance of the interplay of probed polymer's semi-flexibility and crowding anisotropy. Firstly, both ring and linear polymers show a non-trivial dimensional change including nonmonotonicity and collapse-swelling crossover as their stiffness increases. Secondly, we modulate rod crowder length to investigate the anisotropic effect. We reveal that the formation of an ordered parallel arrangement of the environment can effectively lead to a remarkable stretching effect on the probed polymer. The coupling between the crowding anisotropy-induced stretching and the polymer stiffness can account for the unusual swelling behavior. Lastly, nonmonotonic swelling and shape change of the ring polymer are analyzed. We find out that the ring polymer is subject to most pronounced swelling at robust stiffness. Moreover, the maximum prolate shape is also observed at the same robust location.

Food-borne bacteria have received increasing attention due to their great impact on human health. Bioimaging makes it possible to monitor bacteria inside the living body in real time and in situ . Nano-luciferase (NLuc) as a new member of the luciferase family exhibits superior properties than the commonly used luciferases, including small size, high stability and improved luminescence. Herein, NLuc, CBRLuc and FLuc were well expressed in varied food-borne bacteria. Results showed that the signal intensity of E. coli -NLuc was about 41 times higher than E. coli -CBRLuc, L. plantarum -NLuc was nearly 227 times that of L. plantarum -FLuc in vitro. Moreover, NLuc was applied to trace L. plantarum and E. coli in vivo through the whole body and separated digestive tract imaging, as well as the feces bacterium counting and probing. The persistence of bioluminescent strains was predominantly localized in colon and cecum of mice after oral administration. The NLuc system showed its incomparable superiority, especially in the application of intestinal imaging and the universality for food-borne bacteria. We demonstrated that the NLuc system was a brilliant alternative for specific application of food-borne bacteria in vivo , aiming to collect more accurate and real-time information of food-borne bacteria from the living body for further investigation of their damage mechanism and nutrition effect., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

To study the structural influence, hybrid amphiphilic copolymer (G2C 18 ) and linear amphiphilic copolymer (PEG 45 C 18 ) were utilized to prepare docetaxel (DTX)-loaded nanoparticles through an antisolvent precipitation method. The different architectures of the hydrophilic portion affected the particle sizes significantly, and then induced the different antitumor activity. Compared with DTX/PEG 45 C 18 nanoparticles, the antitumor efficacy of DTX/G2C 18 nanoparticles was significantly enhanced, the IC 50 value was 2.1-fold lower in vitro , and the inhibition rate was 1.3-fold higher in vivo . These results suggested that the antitumor activity was significantly affected by the architecture of the nanocarriers, and should be considered when nanocarriers are designed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Two efficient photosensitizers (PSs) with aggregation-induced emission characteristics were designed and synthesized for specific lysosome-targeted photodynamic therapy (PDT). Both PSs efficiently discriminated Gram-positive bacteria from Gram-negative bacteria and killed Gram-positive bacteria through the PDT effect.

Hg 2+ is highly toxic and hazardous and widely found in polluted water. To remove mercury ions from wastewater, there is an urgent need to investigate and develop new adsorbents. Herein, we synthesized three novel thioether-based metal-organic frameworks (MOFs) through a facile diffusion method or a solvothermal strategy, i.e. [(ZnCl 2 ) 3 (L 1 ) 2 ·χ(solvent)] n (1), [(Cu 2 I 3 O 2 ) 4 (CH 4 N 0.5 ) 4 (L 1 ) 4 (DMA) 4 ·3(H 2 O)·χ(solvent)] n (2) and [(CuBr 2 ) 2 (L 2 ) 2 CH 3 CN·χ(solvent)] n (3), where L 1 = 1,3,5-tris((pyridin-4-ylthio)methyl)benzene and L 2 = 2,4,6-trimethoxy-1,3,5-tris((pyridin-4-ylthio)methyl)benzene. The obtained thioether-based MOFs were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, elemental analysis and thermogravimetric analysis. Further studies revealed that they could remove Hg 2+ from water. They have high adsorptivity (up to 362 mg g -1 ) and are highly efficient in removing Hg 2+ (up to 95%). Besides, these MOFs can be recycled and can selectively remove Hg 2+ from water in the presence of other metal ions. Consequently, these MOFs are highly promising candidates for the selective absorption and removal of mercury ions from water.

Methyl N -phenyl carbamate (MPC) is an important intermediate for the green synthesis of methylene diphenyl diisocyanate (MDI) as well as many other important products. In the present work, Zn/Al/Ce mixed oxides derived from hydrotalcite-like precursors were employed as effective and recoverable heterogeneous catalyst for MPC synthesis via DMC aminolysis. Zn/Al/Ce hydrotalcite-like precursors prepared via coprecipitation method and the resulting catalysts were characterized by means of XRD, BET, SEM and XPS. Strong interactions within the Zn/Al/Ce mixed oxides were observed via the addition of appropriate amount of cerium. The mixed oxides containing 2.5% cerium showed high DMC aminolysis activity giving aniline conversion of 95.8%, MPC selectivity of 81.6% and MPC yield of 78.2%. Moreover, as a heterogeneous catalyst, it also exhibited superiorities of easy recovery and recyclable stability for MPC synthesis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The anomalous diffusion dynamics of an active particle in polymer solutions is studied based on a Langevin Brownian dynamics simulation. Firstly, the mean-square displacement (MSD) is investigated under various system parameters of active force F a , probe size σ a , polymer volume fraction φ and polymer chain length N. A very novel transition between superdiffusion and subdiffusion is observed with varying F a and φ, owing to the activity and crowding competition effect. The two anomalous diffusion regimes are identified in the parameter space diagram. The increment of the MSD under activity is examined on intermediate time scales, which manifests a power law relation with the particle's dynamical persistence length L, i.e., ΔMSD = 2L m , where the exponent m decreases with φ. Secondly, we explicitly evaluate the long-time diffusion coefficients D in a pure solvent and D a in polymer solutions. The dependence of relative diffusivity D a /D on volume fraction φ reproduces the well-known Phillies' equation exp(-κφ μ ). The fitting parameters show μ≃ 1, but κ apparently increases with activity. More importantly, our simulation justifies a multi-length scaling relation in a very similar form to that for passive probes, depending on simple structural parameters of the probe-polymer system. With the aid of an activation energy model, we find a counterintuitive activity-crowding coupling effect: activity enhances the effective viscosity experienced by the probe and thus strengthens the crowding-induced slowing of diffusion.

Two-dimensional (2D) materials are expected to be utilized as electrodes for alkali metal ion batteries due to their exceptional properties, but the larger size of K ions has been supposed to induce structural collapses and low charge-discharge efficiency. In this work, we propose transition metal dichalcogenide (TMD) materials as the anode electrodes for potassium ion batteries (PIBs). K ions can stably be adsorbed on most of the TMD materials with strong adsorption energies, and the structural phase transition from the 2H phase to the 1T phase can further enhance the K adsorption. It is surprising that, the diffusion barriers for K ions on TMD monolayers are low enough (less than 0.05 eV) to allow K ions to freely migrate. Among the TMD materials that we consider here, both VS 2 and TiS 2 exhibit extraordinary properties with good electronic conductivity, fast K diffusion, optimal open circuit voltage and high theoretical K storage capacity, which are promising anode materials for K ion batteries.

We report herein that copper alkynyl nanoclusters show metal-core dependent properties via a charge-transfer mechanism, which enables new understanding of their structure-property relationship. Initially, nanoclusters 1 and 2 bearing respective Cu(i) 15 ( C1 ) and Cu(i) 28 ( C2 ) cores were prepared and revealed to display near-infrared (NIR) photoluminescence mainly from the mixed alkynyl → Cu(i) ligand-to-metal charge transfer (LMCT) and cluster-centered transition, and they further exhibit thermally activated delayed fluorescence (TADF). Subsequently, a vanadate-induced oxidative approach to in situ generate a nucleating Cu(ii) cation led to assembly of 3 and 4 featuring respective [Cu(ii)O 6 ]@Cu(i) 47 ( C3 ) and {[Cu(ii)O 4 ]·[VO 4 ] 2 }@Cu(i) 46 ( C4 ) cores. While interstitial occupancy of Cu(ii) triggers inter-valence charge-transfer (IVCT) from Cu(i) to Cu(ii) to quench the photoluminescence of 3 and 4 , such a process facilitates charge mobility to render them semiconductive. Overall, metal-core modification results in an interplay between charge-transfer processes to switch TADF to semiconductivity, which underpins an unusual structure-property correlation for designed synthesis of metal nanoclusters with unique properties and functions., (This journal is © The Royal Society of Chemistry 2019.)

Previously, we designed and synthesized a series of bis-substituted aromatic amide-based histone deacetylase (HDAC) inhibitors. In this study, we report the replacement of a bromine atom by different amides on the phenyl ring of the CAP region. Representative compounds 9d and 10k exhibited low nanomolar IC 50 values against HDAC1, which were ten times lower than that of the positive control SAHA. The IC 50 of 9d against the human A549 cancer cell line was 2.13 μM. Furthermore, 9d increased the acetylation of histones H3 and H4 in a dose-dependent manner. Moreover, 9d significantly arrested A549 cells at the G2/M phase and induced A549 cell apoptosis. Finally, molecular docking investigation rationalized the high potency of compound 9d ., (This journal is © The Royal Society of Chemistry 2019.)