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Ce-doped Ce xBi2 − xTe2.7Se0.3 ( x = 0-0.3) nanopowders were synthesized by the hydrothermal method and the obtained nanopowders were hot-pressed into bulk at 673 K under a pressure of 60 MPa in vacuum. The results show that Ce doping has significant effects on the morphologies of the nanopowders. With increasing Ce doping amount the morphology of the nanopowder changes from nanosheets to nanorods. The thermoelectric (TE) properties measurements show that Ce doping can increase the electrical conductivity greatly, but has little effect on improving Seebeck coefficient and thermal conductivity. There is an optimum value of Ce doping amount. The Ce0.2Bi1.8Se0.3Te2.7 sample shows a highest figure of merit of 0.85 at 413 K as compared to other samples prepared in same conditions. [ABSTRACT FROM AUTHOR]

Indium (In) metal whiskers/nanowires, In2O3 nanowires, nanoscale In2O3 cubes and octahedrons are synthesized by heating In chunks at high temperature in Ar flow at ambient pressure. The In whiskers/nanowires have low melting point and thus can be evaporated (burnt) by the illumination of intensive electron beam, and provide a candidate to be used as solder and fuse in the nano-electronics. Different morphologies of In2O3 products, especially the nanoscale In2O3 cubes and octahedrons are firstly obtained by the traditional chemical vapor deposition process other than the solution one, which may indicate a new way to fabricate other kinds of nanoscale polyhedrons. [Copyright &y& Elsevier]

Semiconducting metal oxides can detect low concentrations of NO2 and other toxic gases, which have been widely investigated in the field of gas sensors. However, most studies on the gas sensing properties of these materials are carried out at high temperatures. In this work, Hollow SnO2 nanofibers were successfully synthesized by electrospinning and calcination, followed by surface modification using ZnO to improve the sensitivity of the SnO2 nanofibers sensor to NO2 gas. The gas sensing behavior of SnO2/ZnO sensors was then investigated at room temperature (~20 °C). The results showed that SnO2/ZnO nanocomposites exhibited high sensitivity and selectivity to 0.5 ppm of NO2 gas with a response value of 336%, which was much higher than that of pure SnO2 (13%). In addition to the increase in the specific surface area of SnO2/ZnO-3 compared with pure SnO2, it also had a positive impact on the detection sensitivity. This increase was attributed to the heterojunction effect and the selective NO2 physisorption sensing mechanism of SnO2/ZnO nanocomposites. In addition, patterned electrodes of silver paste were printed on different flexible substrates, such as paper, polyethylene terephthalate and polydimethylsiloxane using a facile screen-printing process. Silver electrodes were integrated with SnO2/ZnO into a flexible wearable sensor array, which could detect 0.1 ppm NO2 gas after 10,000 bending cycles. The findings of this study therefore open a general approach for the fabrication of flexible devices for gas detection applications. [ABSTRACT FROM AUTHOR]

Hydrogel sensors are widely utilized in soft robotics and tissue engineering due to their excellent mechanical properties and biocompatibility. However, in high‐water environments, traditional hydrogels can experience significant swelling, leading to decreased mechanical and electrical performance, potentially losing shape, and sensing capabilities. This study addresses these challenges by leveraging the Hofmeister effect, coupled with directional freezing and salting‐out techniques, to develop a layered, high‐strength, tough, and antiswelling PVA/MXene hydrogel. In particular, the salting‐out process enhances the self‐entanglement of PVA, resulting in an S‐PM hydrogel with a tensile strength of up to 2.87 MPa. Furthermore, the S‐PM hydrogel retains its structure and strength after 7 d of swelling, with only a 6% change in resistance. Importantly, its sensing performance is improved postswelling, a capability rarely achievable in traditional hydrogels. Moreover, the S‐PM hydrogel demonstrates faster response times and more stable resistance change rates in underwater tests, making it crucial for long‐term continuous monitoring in challenging aquatic environments, ensuring sustained operation and monitoring. [ABSTRACT FROM AUTHOR]

Actuators based on shape memory polymers and composites incorporating nanomaterial additives have been extensively studied; achieving both high output stress and precise shape change by low‐cost, scalable methods is a long‐term‐desired yet challenging task. Here, conventional polymers (polyurea) and carbon nanotube (CNT) fillers are combined to fabricate reinforced composite fibers with exceptional actuation performance, by a wet‐spinning method amenable for continuous production. It is found that a thermal‐induced shrinkage step could obtain densified strong fibers, and the presence of CNTs effectively promotes the tensile orientation of polymer molecular chains, leading to much improved mechanical properties. Consequently, the CNT/ polyurea composite fibers exhibit stresses as high as 33 MPa within 0.36 s during thermal actuation, and stresses up to 22 MPa upon electrical stimulation enabled by the built‐in conductive CNT networks. Utilizing the flexible thin fibers, various shape change behavior are also demonstrated including the conversion between different structures/curvatures, and recovery of predefined simple patterns. This high‐performance composite fibers, capable of both thermal and electrical actuation and produced by low‐cost materials and fabrication process, may find many potential applications in wearable devices, robotics, and biomedical areas. [ABSTRACT FROM AUTHOR]

Currently, bismuth telluride-based zone-melted ingots dominate the commercial thermoelectric (TE) market. However, bismuth telluride-based zone-melted ingots with a layered lattice structure are brittle, posing challenges for their application in miniature devices. Their polycrystalline alloys have robust mechanical strength. However, the electrical conductivity of a p -type polycrystalline BiSbTe alloy bulk deteriorates. In the current study, the Bi 0.46 Sb 1.54 Te 3 powder was from crushed zone-melted ingots. Large-sized polycrystalline (CuO) x Bi 0.46 Sb 1.54 Te 3 (x = 0, 0.003, 0.01, 0.03 and 0.1) bulks were prepared via the hot-pressing method under 65 MPa at 510°C for 15 min. The electrical conductivity was improved remarkably by the acceptor doping effect. The bipolar effect of the Seebeck coefficient and thermal conductivity at high temperatures was suppressed significantly due to increased majority carrier centration and enlarged bandgaps. Consequently, their TE performance (the dimensionless TE figure of merit, ZT) was significantly improved and the ZT max and ZT ave reached 1.4 and 1.27, respectively. [ABSTRACT FROM AUTHOR]

In this report, we have prepared a magnetic catalyst with well-dispersed Ni nanoparticles embedded in SiO2@C core-shell materials. A resorcinol-formaldehyde (RF) resin layer containing Ni source was in situ grown on the SiO2 spheres through polymerization process. The Ni species and RF layer in the precursor simultaneously were transformed into Ni nanoparticles and carbon layer through the heat treatment. The loading mass and size of Ni nanoparticles can be adjusted by changing the additional amount of Ni source, which can provide efficient active sites and control the catalytic reduction of 4-NP. As-prepared SCN-3 with the higher density dispersion revealed better catalytic activity than other catalysts in terms of shorter induction time (70 s) and higher mass-normalized rate constant (261.44 s−1 mg−1). Moreover, SiO2@C/Ni nanocomposite provided an excellent catalytic efficiency with no obvious deactivation (~ 100%) over the 5 cycles. [ABSTRACT FROM AUTHOR]

The Bi 2 Te 3 -based thermoelectric crystal ingots produced by the zone-melting (ZM) are the most widely used commercially at present. However, the poor mechanical properties caused by the ZM are unfavorable to the production of miniature devices. The mechanical properties can be improved by the powder metallurgy (PM), but the PM results in performance degradation of n -type Bi 2 Te 3 -based alloys, which could be attributed to the disappearance of intrinsic anisotropy and the increased carrier concentration originated from the "donor-like" effect of grain boundary. In this paper, the Bi 2 Te 2.7 Se 0.3 + 4 wt % Te (BTST) powder was from the ground ZM ingots, and the influence of CuO doping on the thermoelectric properties of hot-pressed BTST polycrystalline bulks with a large size was investigated. It can be found that the thermoelectric properties of BTST are improved remarkably by CuO doping due to the increased Seebeck coefficient and suppressed thermal conductivity, which is caused by the synthetic effects of optimised carrier concentration, increased effective mass, and enhanced phonon scattering by the Cu 2 Te/Bi 2 Te 2.7 Se 0.3 hetero-interfaces. Finally, the dimensionless thermoelectric figure of merit (ZT) of the sample (CuO) 0.1 (Bi 2 Te 2.7 Se 0.3 + 4 wt % Te) reaches 1.32 at 408 K, which is about 65 % higher than that of the pristine BTST, and its average ZT ave value reaches 1.27 in the temperature range of 300–473 K. The large size bulks produced by this method are not only commercialized directly, but also avoid the problem of poor mechanical properties. • Effects of CuO doping on the thermoelectric properties of Bi 2 Te 2.7 Se 0.3 + 4 wt% Te. • Simultaneous optimization of power factors (S2σ) and thermal conductivity (κ). • High peak ZT max of 1.32 at 408 K, and high average ZT ave of 1.27 from 300 K to 473 K. • Large size of 30 mm*30 mm*70 mm. [ABSTRACT FROM AUTHOR]

Bi 2 Te 3 -based crystal ingots produced by zone melting (ZM) are the most widely used materials to manufacture commercial thermoelectric (TE) devices. However, the poor mechanical properties of such crystalline materials limit the production of small-scale devices. While processability can be improved by powder metallurgy (PM), it also leads to the deterioration of the TE properties due to the donor-like effect of the introduced defects and grain boundaries. Thus, additional efforts towards re-optimizing doping are required. Here, we report a PM method to improve the mechanical properties of Bi 2 Te 3 -based TE materials through the crushing and hot pressing of Bi 2 Te 3 ingots obtained by ZM. Besides, we demonstrate the TE properties of n-type Bi 2 Te 2.7 Se 0.3 (BTS) to be remarkably improved by Cu doping, which enables optimization of the carrier concentration and enhances phonon scattering at heterointerphases thus increasing the Seebeck coefficient and reducing thermal conductivity. Overall, optimized materials reach dimensionless TE figures of merit (ZT) up to 1.16 at 408 K, i.e. 45% higher than that of state-of-the-art BTS, and an average ZT value of 1.08 in the temperature range of 300–473 K. [ABSTRACT FROM AUTHOR]

[Display omitted] • By incorporating MXene nanosheets and Fe3+ into the hydrogel network, rapid gelation (within 10 s) was achieved. • This dual-network conductive hydrogel composite exhibited outstanding stretchability, extremely low energy dissipation. • This work provides a feasible platform for developing integrated wearable health-monitoring electronic systems. Hydrogel-based functional materials had attracted great attention in the fields of artificial intelligence, soft robotics, and motion monitoring. However, the gelation of hydrogels induced by free radical polymerization typically required heating, light exposure, and other conditions, limiting their practical applications and development in real-life scenarios. In this study, a simple and direct method was proposed to achieve rapid gelation at room temperature by incorporating reductive MXene sheets in conjunction with metal ions into the chitosan network and inducing the formation of a polyacrylamide network in an extremely short time (10 s). This resulted in a dual-network MXene-crosslinked conductive hydrogel composite that exhibited exceptional stretchability (1350 %), remarkably low dissipated energy (0.40 kJ m−3 at 100 % strain), high sensitivity (GF = 2.86 at 300–500 % strain), and strong adhesion to various substrate surfaces. The study demonstrated potential applications in the reliable detection of various motions, including repetitive fine movements and large-scale human body motions. This work provided a feasible platform for developing integrated wearable health-monitoring electronic systems. [ABSTRACT FROM AUTHOR]

Zinc electroplating/stripping is a promising electrochemical reaction for aqueous battery anodes, offering advantages such as high safety, low cost, and fast reaction kinetics. However, the growth of zinc dendrites is a major obstacle impeding its commercialization. To address these challenges, a phosphorus‐doping strategy is proposed for preparing a high Zn‐affinity C3N4 coupled carbon nanotube 3D framework (PCN‐S). The addition of P facilitates the efficient crystallization of Zn that leads to the formation of a "concrete‐slab"‐like zinc layer on the PCN‐S surface. Moreover, the unique "release effect" possessed by the P‐doped 3D framework contributes to more stable cycling at high current. Such structural characteristics result in significantly enhanced stability of Zn metal deposition and extend the cycle life of full cells. The Zn@PCN‐S//Zn@PCN‐S symmetric cell exhibits an impressive long‐term cycle time exceeding 1500 h (1 mA cm‒2). Consequently, aqueous rechargeable zinc‐metal batteries constructed with the 3D Zn@PCN‐S anode can achieve a specific energy of approximately ≈340 mAh g‒1 and cycling for over 600 h. This work introduces a promising option for next‐generation energy storage technologies. [ABSTRACT FROM AUTHOR]

Flexible gas sensors, which can detect gas markers from the human body and hazardous gases from the environment, are attracting tremendous attention recently. Carbon nanotube (CNT) films are explored for flexible gas sensors due to its sensing ability at room temperature, strong adsorption for foreign molecules, mechanical robustness, and remarkable flexibility, and providing nanoscale surfaces with large surface area for various functional materials, etc. In this paper, recent advances in flexible gas sensors based on CNT films are reviewed. It discusses various strategies to design the structure of flexible CNT films and improve flexibility/stretchability performance. It generalizes different types of sensitive materials loaded for detected gases and analyzes the sensing mechanism of CNT films, with interface interactions and synergistic effects leading to an improvement in gas sensing. In addition, it discusses the preparation of CNT self‐standing films and the use of flexible substrates in transformation and assembly, in order to enable CNT films with improved flexible properties. CNT films show remarkable response and flexibility to hazard or greenhouse gases, such as ammonia, nitrogen dioxide, hydrogen, nitric oxide, carbon dioxide, and others. Summary and perspectives toward the future development of flexible gas sensors based on CNT films are proposed. [ABSTRACT FROM AUTHOR]

Compared with hydrogen evolution reaction (HER) under acidic conditions, the kinetic steps of alkaline HER are more complex, which involves the adsorption and cleavage of water molecules. Defect and interface engineering are two important means to enhance basic HER. In order to prepare catalysts with high activity and stability under both acidic and basic conditions, a defective amorphous carbon loaded with Ru nanoparticles coaxially wrapped around a carbon nanotube (CNT) sponge network is presented. The presence of amorphous carbon can promote the uniform loading of Ru nanoparticles and limit the growth of Ru nanoparticles, and also the introduction of oxygen defects can regulate the electronic structure of the metal and improve its charge transport capacity, thus enhancing the catalytic performance. The catalyst CNT/C/Ru0.37 wt%‐700 prepared under optimized conditions exhibits excellent stability and activity. At a current density of 10 mA cm−2, the overpotential of HER is as low as 38.3 and 36.2 mV under alkaline and acidic conditions, respectively, which is better than most reported Ru‐based catalysts. This study details innovative and feasible ideas for the design and preparation of loaded catalysts, which can contribute to the development of high‐performance electrochemical catalysts. [ABSTRACT FROM AUTHOR]

Fiber‐based electronic devices can be woven into textiles to provide comfort, durability, and integrated multi‐functionality, and will be widely used in the intelligent wearable field. Herein, by introducing elastic substrates and regulating the external tension during spinning to control the helical structure and optimize mechanical properties, multi‐functional Polyurethane@carbon nanotube (PU@CNT) stretchable fibers with high extensibility and flexibility is prepared for human motion detection and energy storage. A multi‐layered structure consisting of alternating MXene sheets and CNT films is also designed, to promote the relative resistance change of PU@CNT/MXene fibers to 212% (4 times than PU@CNT) when acting as strain sensors, whereas their volume specific capacitance reaches 196 F cm−3 (increases ≈50 times). Additionally, the capacitance of our stretchable fibers supercapacitors maintains at 91.4% and 86.2% when stretched statically (170% strain) or after hundreds of cycles (50% strain), respectively. It is proposed that MXene sheets can fill gaps between CNTs, resulting in more uniform distribution in fibers, which can improve strain sensitivity and long‐cycle capacitance retention. These PU@CNT/MXene fibers with unique multi‐layered hybrid structure and superior performance have potential applications in portable, wearable, and body‐integrated sensors and energy storage devices. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of extracellular Aβ42 on neural cell migration, and the possible molecular mechanisms. Extracellular Aβ42 monomers did not negatively affect the motility of neural cells; however, they could promote cell migration from toxic extracellular Aβ42 oligomers. Contrastingly, extracellular Aβ42 aggregates, especially Aβ42 oligomers, significantly decreased neural cell migration while reducing their survival. Further, their soluble and deposited states showed different effects in causing the neural cells to become inert (incapable of moving). These findings were consistent with that of binding of Aβ42 oligomers to the plasma membrane or integrin receptors of the inert cells. By combining the protection of cell migratory capability by anti-oligomeric Aβ42 scFv antibody with the information obtained from our docking model of the Aβ42 trimer and integrin molecule, our findings suggest that extracellular Aβ42 aggregates disrupt the function of integrins mainly through the RHDS motif of Aβ42 chain, which eventually causes neural cells to become inert. Thus, we propose an "anchor" opinion, where Aβ42 aggregates in the ECM serve as the adverse "anchors" in the brain for anchoring neurons and for making neural cells inert, which causes their dysfunction. The neural cells with damaged motility could be restored or repaired if these anchoring effects of extracellular Aβ42 aggregates on the neural cells were severed or reduced, even if the "anchors" themselves were not completely eliminated. Medicines targeting soluble and deposited anchors of Aβ42 aggregates could be developed into effective treatments for Alzheimer disease. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) Mxene (Ti 3 C 2 T x) is an emerging reinforcement. Due to its high aspect ratio and abundant surface functional groups, Ti 3 C 2 T x is widely used in polymer matrix composites and metal matrix composites (MMCs). In composites, the strengthening effect of Ti 3 C 2 T x is closely related to its lateral size, which is usually difficult to be controlled macroscopically. In this work, the Ti 3 C 2 T x flakes with two different lateral sizes are prepared by etching Ti 3 AlC 2 powders with different sizes. The lateral size of Ti 3 C 2 T x flakes prepared by etching 400 mesh Ti 3 AlC 2 powders is about 0.67 μm (F1), and that of Ti 3 C 2 T x flakes prepared by etching 200 mesh Ti 3 AlC 2 powders is about 1.83 μm (F2). The F1/ZK61 and F2/ZK61 composites are prepared by spark plasma sintering. The hardness and compressive yield strength (CYS) of the F1/ZK61 composite increased by 16.5% and 8.2%, respectively. The hardness and CYS of the F2/ZK61 composite increased by 7.9% and 5.3%, respectively. This work reveals the effects on mechanical properties by controlling the lateral size of Ti 3 C 2 T x flakes in the Ti 3 C 2 T x /ZK61 composites. [ABSTRACT FROM AUTHOR]

Aggregation and deposition of amyloid beta-protein 1–42 (Aβ42) in the brain, primarily owing to hydrophobic interactions between Aβ42 chains, is a common pathology in all forms of Alzheimer's disease (AD). Hydrophilic oligosaccharides are widely present in the extracellular matrix and on the cytoplasmic membrane. To determine if oligosaccharides bind to Aβ42 or its aggregates and consequently affect their aggregation and cellular function, this study examined the interaction of typical functional oligosaccharides with Aβ42 or its aggregates. Isomaltooligosaccharides (IMOs), particularly isomaltotriose, panose, and isomaltotetraose, functioned as molecular chaperones for Aβ42 by binding directly to Aβ42, preserving Aβ42's active conformation and cytotrophic activity. Oral IMOs reduced total plasma Aβ level and indirectly caused a slight reduction in the load of Aβ42 spots/plaques in the brain of AD model mice (male). Another branched oligosaccharide, bianntennary core pentasaccharide (BCP), had a relatively high binding specificity for Aβ42 oligomers (Aβ42O) and acted as an antagonistic binding partner for Aβ42O. Free BCP effectively blocked/prevented further assembly of Aβ42O and their toxicity to neural and vascular endothelial cell lines. Since BCP is also a signaling component of membrane targets (glycolipids, glycoproteins or receptors), it seemed that BCP had two opposing effects on the binding of Aβ42O to target cells. This study's findings suggest that these branched oligosaccharides may be potential candidates for blocking or preventing Aβ42 aggregation and Aβ42O cytotoxicity/neurotoxicity, respectively, and that IMO-like or free BCP-like oligosaccharide deficiencies in the brain may be one of the underlying mechanisms for Aβ42 aggregation and Aβ42O cytotoxicity. [Display omitted] • IMOs functioned as molecular chaperones for Aβ42 by binding directly to Aβ42. • IMOs preserve Aβ42's active conformation and cytotrophic activity. • BCP acted as an antagonistic binding partner for Aβ42O. • Free BCP effectively blocked/prevented Aβ42O cytotoxicity/neurotoxicity. [ABSTRACT FROM AUTHOR]

Extracellular amyloid β-protein (1-42) (Aβ42) aggregates have been recognized as toxic agents for neural cells in vivo and in vitro. The aim of this study was to investigate the cytotoxic effects of extracellular Aβ42 aggregates in soluble (or suspended, SAβ42) and deposited (or attached, DAβ42) forms on cell adhesion/re-adhesion, neurite outgrowth, and intracellular scaffold palladin using the neural cell lines SH-SY5Y and HT22, and to elucidate the potential relevance of these effects. The effect of extracellular Aβ42 on neural cell adhesion was directly associated with their neurotrophic or neurotoxic activity, with SAβ42 aggregates reducing cell adhesion and associated live cell de-adherence more than DAβ42 aggregates, while causing higher mortality. The reduction in cell adhesion due to extracellular Aβ42 aggregates was accompanied by the impairment of neurite outgrowth, both in length and number, and similarly, SAβ42 aggregates impaired the extension of neurites more severely than DAβ42 aggregates. Further, the disparate changes of intracellular palladin induced by SAβ42 and DAβ42 aggregates, respectively, might underlie their aforementioned effects on target cells. Further, the use of anti-oligomeric Aβ42 scFv antibodies revealed that extracellular Aβ42 aggregates, especially large DAβ42 aggregates, had some independent detrimental effects, including physical barrier effects on neural cell adhesion and neuritogenesis in addition to their neurotoxicity, which might be caused by the rigid C-terminal clusters formed between adjacent Aβ42 chains in Aβ42 aggregates. Our findings, concerning how scaffold palladin responds to extracellular Aβ42 aggregates, and is closely connected with declines in cell adhesion and neurite outgrowth, provide new insights into the cytotoxicity of extracellular Aβ42 aggregates in Alzheimer disease. [ABSTRACT FROM AUTHOR]

Metal/semiconductor composites are promising catalysts. In this work, the three-dimensional flowery Ag@NiO micro-nanocomposite catalyst for the highly fast reduction of 4-nitrophenol to 4-aminophenol was prepared by simple homogeneous precipitation method. Ag@NiO composites exhibit better catalytic performance than Ag and NiO in reducing 4-nitrophenol. The catalytic experiments showed that when the specific surface area of Ag@NiO was 20.61 m2/g, the complete conversion time of 4-nitrophenol to 4-aminophenol was the shortest, the reaction kinetic constant was 11.01 × 10−3 s−1, and the turnover frequency was 166.67 × 10−5 mol·g−1·s−1. The catalytic activity of Ag@NiO was not significantly reduced after five consecutive cycles. Furthermore, the synergistic effect of Ag and NiO of the Ag@NiO composites was investigated in this work. Ag@NiO micro-nanomaterials have the potential for industrial application with simple preparation method, high catalytic efficiency, and easy recycling. [ABSTRACT FROM AUTHOR]

In this work, one-dimensional (1D) NiCo2S4 nanotubes with sulfur vacancies (Vc-NiCo2S4) were designed effectively via the electrostatic spinning and chemical bath deposition (CBD) process. As-spun polyacrylonitrile (PAN) nanofibers containing surfactant were taken as hard templates. Through the in-situ growth and etching process, NiCo2S4 nanotubes covered with a large number of nanosheets were generated. Sulfur vacancies were introduced by the following chemical reduction. The influence of defects was systematically discussed through structure analyses and electrochemical properties. As-obtained Vc-NiCo2S4 not only maintains the original hierarchical nanotube characteristic, but also boost the electrochemical behaviors. Due to the defect treatment, Vc-NiCo2S4 nanotubes have a higher specific capacity (1046 F g−1 at a current density of 1 A g−1) and enhanced rate capability. A symmetrical supercapacitor (SSCs) device assembled by Vc-NiCo2S4 nanotubes displays a high energy density of 31.8 Wh kg−1 at the power density of 260 W kg−1. These results indicate that the construction of 1D hierarchical nanotubes and sulfur vacancies could provide effective strategy to promote the performance of supercapacitors. 1D NiCo2S4 hierarchical nanotubes were prepared by employing PAN nanofibers as sacrificial templates. The Vc-NiCo2S4 nanotubes after NaBH4 reduction maintain the original morphology and optimize the electrochemical activities. Vc-NiCo2S4 with sulfur vacancies exhibits enhanced electrochemical performance. [ABSTRACT FROM AUTHOR]

The size of reinforcements is a pivotal and conventional parameter in metal matrix composites. Based on the distinctive preparation process of MXene, this research introduces a novel strategy to tailor the size of Ti 3 C 2 T x through the controlled ball milling of its precursor, Ti 3 AlC 2. This approach fabricated Ti 3 C 2 T x sheets with sizes of 4.7 µm, 1.8 µm, and 0.6 µm. Subsequently, these Ti 3 C 2 T x sheets are incorporated into a magnesium (Mg) matrix composite to investigate the effect of Ti 3 C 2 T x size on the strengthening performance. The findings reveal a trend wherein the compressive yield strength (CYS) of the Ti 3 C 2 T x /ZK61 composites increases and the failure strain decreases with the decreased size of Ti 3 C 2 T x. Incorporating 4.7 µm Ti 3 C 2 T x results in an 11.0% reduction in CYS coupled with a 50% increase in failure strain. Incorporating 1.8 µm Ti 3 C 2 T x leads to a 4.6% increase in CYS with a 6.5% increase in failure strain. Incorporating 0.6 µm Ti 3 C 2 T x leads to a 10.7% increase in CYS with a 3.2% increase in failure strain. • Ti 3 C 2 T x sheets with continuously decreased size are successfully prepared by etching the ball milled Ti 3 AlC 2 powders. By etching the Ti 3 AlC 2 powders with different size, the average size of the obtained Ti 3 C 2 T x sheets can be regulated. • The CYS increases and the failure strain decreases continuously with the decreased size of Ti 3 C 2 T x. It is indicated that the size of Ti 3 C 2 T x is strongly associated with the strengthening and toughening effect in ZK61 composites. • When the Ti 3 C 2 T x size is less than 3 µm, the strength increment of the Orowan strengthening varies fast with the changed Ti 3 C 2 T x size, but the load transfer strengthening varies very slowly due to the large aspect ratio and small thickness. [ABSTRACT FROM AUTHOR]

Abstract Amyloid-beta 42 (Aβ42) aggregates represent a prominent histopathological feature in Alzheimer's disease (AD); thus, immunotherapy against oligomeric Aβ42 aggregates is considered to be a potentially safe and specific therapeutic strategy. In this study, we identified an anti-oligomeric Aβ42 aggregate single-chain variable fragment (scFv) antibody, HT6, that is capable of efficiently binding to medium-sized Aβ42 aggregates (mainly 18–45 kDa) in vitro with an equilibrium dissociation constant (K D) of 3.0 × 10–6 M, whether they were derived from Aβ42 monomer, larger Aβ42 oligomers, or even fibrils. This ability allowed scFv HT6 to induce the gradual disassembly of large Aβ42 aggregates into small Aβ42 oligomers while simultaneously effectively inhibiting the further development of Aβ42 aggregates. Moreover, the scFv HT6-targeted conformational region on Aβ42 aggregates was found to be more local and relatively close to the N-terminus of Aβ42; thus, scFv HT6 significantly delayed or even prevented the aggregation of Aβ42 protofibrils, while significantly reducing the cytotoxicity of Aβ42 oligomers. Overall, this study demonstrate that even though the decrease in the cytotoxicity of Aβ42 aggregates might be closely related to the reduction in Aβ42 aggregates and vice versa , the reduction in Aβ42 aggregates might not necessarily be accompanied by or followed by the reduction or even elimination of the cytotoxicity of Aβ42 aggregates. This insight enriches the diversity of anti-oligomeric Aβ42 antibodies, further providing a new understanding into the relationship between their binding pattern to Aβ42 aggregates and the efficacy against their formation, offering a therapeutic strategy to delay the progression of AD. Graphical abstract Unlabelled Image Highlights • Efficacy of an anti-oligomeric Aβ42 antibody is mainly related to the specific antibody-targeted site on the Aβ42 aggregate. • Reduction in Aβ42 aggregates does not necessarily mean the reduction of the cytotoxicity of Aβ42 aggregates. • This work provides a new perspective into the binding pattern and related efficacy of an anti-oligomeric Aβ42 antibody. [ABSTRACT FROM AUTHOR]

Abstract Solid-state supercapacitors (SSCs) are under intensive study during recent years; rational design of the electrode structure and device configuration is essential to bring high performance and enable flexibility. Here, we designed a mutually intercalated composite structure consisting of pseudo-polymer (polyaniline, PANI), graphene oxide (GO) and carbon nanotubes (CNTs), in various forms such as planar films or helical fibers. In the prepared PANI/GO/CNT composite films, PANI and GO were uniformly embedded among stacked CNT networks resulting in a synergistic effect from all components; as a result, the film with tunable PANI loading exhibited a specific capacitance of 729.3 F/g (510.5 mF/cm2) at 1 A/g in three-electrode configuration, and symmetric SSCs made by these films showed stable performance upon large-degree bending for 500 cycles. The composite film was further over-twisted into a helical fiber and constructed to fiber-shaped SSCs, which could work stably at elongations as much as 80%. Our polymer/carbon nanostructure composite electrodes that can work under different forms (films or fibers) have potential applications as flexible, stretchable and wearable energy storage devices and textiles. Graphical abstract Unlabelled Image Highlights • A mutually intercalated structure consisting of PANI, GO and CNTs, in various forms such as planar films or helical fibers. • The composite film exhibited a specific capacitance of 729.3 F/g (510.5 mF/cm2) at 1 A/g. • Symmetric SSCs showed stable property upon large-degree bending, fiber-shaped SSCs work stably at elongations as much as 80%. [ABSTRACT FROM AUTHOR]

The process of developing antibody drugs for Alzheimer's disease therapy has been both long and difficult; however, recent advances suggest that antibodies against neurotoxic Αβ42 can suppress the progression of AD, especially on its early stage. Here, we obtained and characterized a novel anti-oligomeric Aβ42 aggregate scFv antibody, HT7, which could induce the significant disaggregation of Aβ42 aggregates through the release of stable and non-cytotoxic hexameric complexes that were composed of three scFv HT7s and one Aβ42 trimer, the latter being found to serve as the assembled subunit within larger Aβ42 aggregates in addition to existing freely between the cells. The docking model of the scFv HT7-Aβ42 complex revealed that only the N-terminal peptide of the Aβ42 molecule was bound into the groove between the VH and VL domains of scFv HT7. Thus, it was suggested that the hydrophobic interaction between the C-terminal peptides of Aβ42 molecules maintained the stability of the Aβ42 trimers or the Aβ42 trimer subunits. The saturation of Aβ42 trimer subunits by scFv HT7 and the subsequent dissociation of the scFv HT7-saturated Aβ42 trimer subunits from larger Aβ42 aggregates constituted the primary mechanisms underlying the high efficacy of scFv HT7. Our findings revealed that it was not sufficient for an anti-oligomeric Aβ42 antibody to exhibit high specificity and high affinity to the oligomeric Aβ42 aggregates in order to promote Aβ42 aggregate clearance and neutralize their cytotoxic effects. Here, for the first time, we proposed a "post-saturation dissociation" mechanism of Aβ42 oligomeric subunits for effective anti-Aβ42 antibodies. [ABSTRACT FROM AUTHOR]

• The unique structure of Ti 2 NbC 2 T x @CDs facilitates the rapid migration of Li+/Na+. • Ti 2 NbC 2 T x @CDs achieves outstanding rate capability and ultra-long cycling life. • Ti 2 NbC 2 T x @CDs shows ideal electrochemical reversibility. Two-dimensional transition metal carbides/nitrides or MXenes, show great promising in energy storage field owing to its excellent electrical and chemical properties, especially for the modifiable surface functional groups, adjustable interlayer spacing and metal-like conductivity. Here, a hybrid electrode based on double transition metal MXene (Ti 2 NbC 2 T x) is designed and synthesized, where nitrogen-doped carbon dots are uniformly anchored on the edge-crumpled Ti 2 NbC 2 T x nanosheets. The unique structure of the hybrid electrode can effectively suppress the self-stacking of MXenes nanosheets, improve the ions/electron transport efficiency and the cycling stability. The Ti 2 NbC 2 T x @CDs hybrid electrode achieves outstanding rate capability and cycling performance for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). At 5 A g−1, up to 10,000 cycles, it can deliver 217.3 mAh g−1 for LIBs and 109.2 mAh g−1 for SIBs. The Ti 2 NbC 2 T x @CDs hybrids show high capacitive contribution, owing to the rapid ions/electrons transporting. The Ti 2 NbC 2 T x @CDs hybrids also show ideal electrochemical reversibility from the in-situ XRD study. This work will help to develop novel double transition metal MXenes and their composite electrode materials for LIBs/SIBs with better performance. [ABSTRACT FROM AUTHOR]

Nano-second-phase dispersion usually improves the thermoelectric properties of thermoelectric materials through energy filtering effects and phonon scattering effects. In this paper, MXene was introduced as a new nano second phase material into the Cu 2 Se alloy bulks prepared by the hydrothermal method and the vacuum hot-pressing method. The microstructure, electrical and thermal transport properties of the samples were studied, and the results showed that the introduction of MXene can not only optimize its electrical transport properties, but also significantly suppress its thermal conductivity, thereby effectively improving its thermoelectric properties. Overall, the maximum ZT value of the Cu 2 Se + 0.20 mol % MXene sample reached 1.77 at 923 K, which was 30 % higher than that of the pristine Cu 2 Se sample. • Mxene dispersant. • Simultaneous optimization of power factors (S2σ) and thermal conductivity (κ). • Improved ZT value by 33 % compared with the pure Cu 2 Se sample. [ABSTRACT FROM AUTHOR]

Single-chain variable fragment (scFv) HS72 is a catalytic antibody that specifically degrades amyloid β-protein 1–42 (Aβ42) aggregates in vitro or reduces the level or burden of Aβ42 deposits/plaques in the brains of mice with Alzheimer disease pathology. Its efficacy has been shown in protecting neural cells in vitro and improving the morphology of the cell population in the brain of mice with AD pathology (AD mice). Matrine (Mat) is a natural product capable of binding to Aβ42 or its aggregates and blocking their neurotoxicity at concentrations of at least 10 μM or greater. However, this study revealed a synergistic effect of Mat on the catalytic effect of HS72 at low concentrations (0.01−2.5 μM). This is evidenced by the fact that Mat synergistically enhances HS72's ability to degrade Aβ42 aggregates and protect neural cells (SH-SY5Y and HT22 cells, and brain cells of AD mice). The molecular docking models and characterization of Mat's action both indicated that the mechanism of Mat's synergistic impact on HS72 catalysis is to increase the turnover number (or molecular activity) of HS72 by enhancing the catalytic power of the HS72's catalytic groups and encouraging the release of the degradation products (Aβ fragments). The study's results suggest a natural synergy between Mat-like small molecules and the catalytic anti-oligomeric Aβ42 antibody HS72, enabling more effective reduction or removal of Aβ42 aggregates or plaques than the antibody alone. These findings provide novel insights into the effectiveness of anti-oligomeric Aβ42 antibodies in AD immunotherapy. • Matrine has a positive synergistic effect on the catalytic activity of the catalytic anti-oligomeric Aβ42 scFv antibody HS72. • The synergy of matrine with the catalytic antibody HS72 makes HS72 more effective than HS72 alone in reducing or removing Aβ42 aggregates or plaques and protecting neural cells. • The mechanism of matrine's synergistic effect on HS72 catalysis is to increase the turnover number (or molecular activity) of HS72 by enhancing the catalytic power of the HS72's catalytic groups and facilitating the release of the degradation products (Aβ fragments). [ABSTRACT FROM AUTHOR]

Laccase (EC1.10.3.2), an oxidase that binds multiple copper ions, is heterogeneous in different species, implying diversity in its function. Nevertheless, the four copper-binding motifs are conserved in most laccases, especially bacterial forms. In order to exploit laccase more widely and more effectively in industrial processes, we investigated the regulatory effects, if any, of the second conserved copper-binding motif in the bacterial laccases CAR2 and CAHH1. The data suggested that three critical amino acid residues His155, His157, and Thr/Ala158 in this motif strongly regulated laccase’s catalysis, substrate range, and robustness. Indeed, these residues were essential for laccase’s catalytic activity. The data also suggested that laccase’s catalytic efficiency and activity are not completely consistent with its stability, and that the enzyme might have evolved naturally to its favor stability. This study provides important insights into the second conserved copper-binding motif and defines some of the previously undefined amino acid residues in this conserved motif and their significances. [ABSTRACT FROM AUTHOR]

In this work, a unique Ppy@NiCo 2 S 4 core-shell heterostructure material is prepared taking polypyrrole (Ppy) nanotubes as skeleton through a simple and environmentally friendly hydrothermal method. The heterostructured structure with Ppy nanotubes (NTs) as the core and intertwined flake-like NiCo 2 S 4 as the outer shell, holds a large specific surface area (217 m 2 g −1 ), convenient charge transport channel, high specific capacitance (908.1 F g −1 at a current density of 1 A g −1 ), and excellent cycling performance (87.7% of initial value is retained after 2000 cycles). What’s more, an asymmetric supercapacitor is fabricated by employing Ppy@NiCo 2 S 4 core-shell heterostructured material as positive and nitrogen-doped carbon nanotubes (N-C NTs) as negative electrode. This Ppy@NiCo 2 S 4 //N-C asymmetric supercapacitor effectively provides a high energy density over 50.82 Wh kg −1 with a high power density of 160 W kg −1 and preeminent cyclic stability of 126.6% after 2000 cycles. Due to the introduction of one-dimensional flexible Ppy inner core, as-designed the core-shell heterostructure composite may be promising in the flexible energy storage devices. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWNTs) have potential for creating high performance gas sensors, but the number of gases that can be detected is still limited and the sensitivity needs further improvement. Here, large-area SWNT films directly synthesized by chemical vapor deposition are configured into gas sensors for a range of toxic gases such as NH 3 , NO, and NO 2 . In particular, a SWNT-Fe 2 O 3 composite film obtained via a simple annealing process produces a stable response to H 2 S and shows enhanced sensitivity to NO 2 and at room temperature, compared with pristine SWNT films. Formation of uniform Fe 2 O 3 nanoparticles throughout the porous film is responsible for improved performance and enabling sensing to more gases, and removes conventional steps such as chemical functionalization or doping. Flexible sensors that can be bent to large angles repeatedly are also demonstrated. SWNT films containing a large amount of residual catalyst can be directly manufactured into large-area, flexible or wearable, thin film or textile-configured sensors for various toxic gases. [ABSTRACT FROM AUTHOR]

In this work, TiO 2 and Zn doped TiO 2 nanoparticles (Zn-TiO 2 NPs) were synthesized and served as SERS-active substrate for the detection of levofloxacin (LVFX) drug molecules. Both experimental and theoretical methods are used to study the enhanced mechanism and interaction between substrate and drug molecule. The results indicate that the LVFX is close to the substrate surface through the carboxyl group. The levofloxacin molecules adsorbed on Zn-TiO 2 NPs exhibit the largest SERS enhancement, when the Zn content is 3%, the adsorption time is 7 h and pH value is 6.78. The detection limit can be reduced to 1.29 × 10 −7 mol/L by this method. And, a quantitative detection method of LVFX can be established. There is a good linear relationship in the range of 1 × 10 −3 –1 × 10 −7 mol/L concentration. [ABSTRACT FROM AUTHOR]

MXenes, a family of the typical two-dimensional materials, that are considered to be an excellent candidate material for supercapacitors, due to their large surface area, high conductivity and high specific pseudocapacitance. However, when assembled into electrode, MXene nanosheets are easy to aggregate because of the strong Van der Waals force. The assembled dense structure will limit the transport of electrolyte, decrease the active sites and electrochemical performance. In this work, in order to suppress the self-restacking of nanosheets and introduce more electrolyte transport channels, Ti 3 C 2 T x nanosheets are partially oxidized and etched to get porous nanosheets. Film electrode based on porous Ti 3 C 2 T x nanosheets shows higher specific surface area (48.3 m2/g) and improved electrochemical performance, including a high specific capacitance of 385 F/g at 1 A/g and good cycle stability of 92 % after 10,000 CV cycles at 100 mV/s. Porous MXene nanosheets are oxidized and etched by H 2 O 2 and dilute HCl. Under the best conditions, the film based on that shows higher specific surface area, more ion transfer channels, high specific capacitance of 385 F/g at 1 A/g and 91 % capacitance retention after 1000 cycles at 100 mV/s. [Display omitted] • A simple way to oxidize and etch pores on MXene nanosheets is designed and studied. • Porous MXene nanosheets with different porosity can be obtained by tuning the reaction conditions. • Film electrodes based on porous MXene nanosheets show improved electrochemical performance. [ABSTRACT FROM AUTHOR]

Oligomeric Aβ42 aggregates have been identified as one of the major neurotoxic components of Alzheimer's disease (AD). Immunotherapy targeted against these Aβ42 aggregates has been proposed as an appropriate therapeutic approach for the treatment of AD. Here, we report an anti-oligomeric Aβ42 single-chain variable fragment (scFv) antibody, named MO6, obtained from the human antibody library of a healthy donor. ScFv MO6 specifically recognized and bound to the oligomeric Aβ42 (Aβ42 oligomers and immature protofibrils; 18–37 kDa), and reduced their levels mainly by blocking their formation, although scFv MO6 also induced disaggregation of Aβ42 aggregates. More importantly, scFv MO6 ameliorated or attenuated Aβ42-induced cytotoxicity and increased cell viability by up to 33%. Furthermore, scFv MO6 efficiently passed through an in vitro blood–brain barrier (BBB) model with a delivery efficiency of 66% after 60 min post-administration. ScFv MO6 is a monovalent antibody with an affinity constant ( K D ) of 5.2 × 10 −6 M for Aβ42 oligomers. Molecular docking simulations of Aβ42 to scFv MO6 revealed that the approach and specific binding of scFv MO6 to oligomeric Aβ42 aggregates was achieved by conformational recognition and directed induction, which resulted in a more dynamic adaptation of Aβ42 to scFv MO6, occurring mainly in the N-terminal (3–4), middle (12–19) and C-terminal (34–42) regions of Aβ42. This binding mode of scFv MO6 to Aβ42 explains its protective effects against oligomeric Aβ42. Our findings may be applied for the design of a smaller antibody specific for Aβ42 oligermers. [ABSTRACT FROM AUTHOR]

Abstract: The B4C nanowires can be easily fabricated by employing an activated carbon, boron and Ni(NO3)2 whereas almost no B4C nanowires can be obtained if activated carbon is replaced by pure carbon. The analyses show that there are Si and Al impurities in the activated carbon, and both Si and Ni are critical to the growth of the B4C nanowires. Additionally, the yield of the B4C nanowires is greatly increased if the B4C nanowires are grown by the carbon nanotubes-confined method when Si is introduced. The mechanism of the Si enhanced growth of B4C nanowires is discussed. [Copyright &y& Elsevier]

Ti 3 C 2 T X (Mxene) is a new attractive reinforcement in composites due to its two-dimensional structure, excellent mechanical properties and active surface, but in metal matrix composites Ti 3 C 2 T X has been neglected for its poor performance. To improve the strengthening ability of Ti 3 C 2 T X in magnesium (Mg) matrix composites, the surface functional groups of Ti 3 C 2 T X are modified by thermal reduction. After thermal reduction, it is found that the oxygen-containing functional groups combined with the inner C atoms in the Ti 3 C 2 T X increase significantly, which reduces the structural stability of Ti 3 C 2 T X and promotes the interface reaction between the Ti 3 C 2 T X and Mg matrix. The violent interface reaction leads to the partial oxidation of Ti 3 C 2 T X sheets and increase of the in-situ synthesized MgO particles, which strengthens the interface bonding. In comparison to the original Ti 3 C 2 T X , the thermally reduced Ti 3 C 2 T X shows a better performance in improving the mechanical properties. This study provides new insights into the interface design and oxides formation mechanism of advanced Ti 3 C 2 T X /Mg matrix composites with enhanced mechanical properties. • After thermal reduction, the oxygen-containing functional groups combined with the inner C atoms in the Ti 3 C 2 T X increase significantly, which reduces the structural stability of Ti 3 C 2 T X and promotes the interface reaction between the Ti 3 C 2 T X and Mg matrix. • The thermal reduced Ti 3 C 2 T X sheets have a violent interface reaction with the Mg matrix, which results in the partial oxidation of Ti 3 C 2 T X sheets and increase of the in-situ synthesized MgO particles. • This structural change strengthens the interface bonding between the Ti 3 C 2 T X sheets and Mg matrix to improve the enhancement of Ti 3 C 2 T X in ZK61 alloy. [ABSTRACT FROM AUTHOR]

Two-dimensional Ti 3 C 2 T X (Mxene) is a new attractive reinforcement in composites due to its high aspect ratio and rich surface functional groups, but in metal matrix composites the enhancement of Ti 3 C 2 T X is far from expectation, which is due to its poor thermal stability and oxidation resistance. To reveal the performance of Ti 3 C 2 T X in magnesium matrix composites, ZK61 alloys reinforced with Ti 3 C 2 T X are fabricated by spark plasma sintering, which are conducted at low sintering temperatures with a relatively short sintering time to maintain the stability of Ti 3 C 2 T X. With 0.5 wt% Ti 3 C 2 T X , the hardness increased by 5.4%, the compressive yield strength (CYS) increased by 28.7% and the failure strain decreased by 6.1%. The Ti 3 C 2 T X shows a relatively high strengthening efficiency and a similar performance as graphene. The Ti 3 C 2 T X distributes uniformly in the grain boundary and is surrounded by the in-situ synthesized MgO nanoparticles, which distribute disorderly in the interface between the Ti 3 C 2 T X and the α-Mg matrix. When the Ti 3 C 2 T X content increases to 1.0 wt%, the hardness and CYS increased further, but the failure strain decreased by 70.7%. The Ti 3 C 2 T X clusters and thicker grain boundary resulted in the grain boundary embrittlement and induced the intergranular fracture, which resulted in the decrease of the strain hardening and uniform elongation. • Most of the Ti 3 C 2 T X remained the complete structure and had a uniform distribution in the grain boundary. • The Ti 3 C 2 T X showed a relatively high strengthening efficiency and a similar performance as graphene. • The Ti 3 C 2 T X was surrounded by the in-situ synthesized MgO nanoparticles, which distributed disorderly in the interface and enhanced the interfacial bonding. [ABSTRACT FROM AUTHOR]

Lightweight magnesium (Mg) alloys suffer from their relatively low strength and limited ductility. The addition of graphene can effectively improve the strength and ductility of Mg alloys. However, the mechanism of improving ductility by graphene in Mg alloys has been generally neglected, as evidenced by a lack of studies. To reveal the mechanism, ZK61 alloys reinforced with reduced graphene oxide (rGO) are fabricated by spark plasma sintering (SPS). After compressive tests in the direction of the axial pressure in SPS (Z direction) and the direction perpendicular to the axial pressure (X/Y direction), the rGO/ZK61 composites exhibit high ductility in the Z direction. Transmission electron microscopy (TEM) reveals that some of the aligned rGO sheets are parallel to the X/Y direction. The aligned rGO sheets show a high ability to suppress deformation twinning in the Z direction and provide high strain hardening. This activates the non-basal slip system to improve ductility, thereby leading to highly uniform elongation and good ductility. [ABSTRACT FROM AUTHOR]

The formation of amyloid β-protein (1–42) (Aβ42) oligomers and Aβ42 oligomer cytotoxicity are two defining characteristics of the etiology of Alzheimer's disease (AD). In this study, we found that matrine (Mat) could maintain or even enhance the cytotrophic effect of Aβ42 monomers by inhibiting their aggregation and by working in a manner similar to synergy with Aβ42 monomers. Moreover, Mat could also exert a cytoprotective effect by actively promoting the disaggregation of immature Aβ42 oligomers in a concentration-dependent manner. Although Mat at intermediate concentrations (1–50 μM) exhibited both cytotrophic and cytoprotective effects on SH-SY5Y cells, Mat at higher concentrations (100 μM) only exhibited a cytoprotective effect. Molecular docking studies reveal that these differences are a result of the different interactions between Mat and Aβ42 oligomers that occur at different molecular ratios. Our results support the hypothesis that there may be a Mat-like metabolite in the human brain that acts as a molecular chaperone for Aβ42 monomers. A deficiency in this chaperone would result in the gradual aggregation of Aβ42 monomers, and eventually, formation of toxic Aβ42 oligomers. In addition, reduction or clearance of Aβ42 aggregates or deposits and inhibition or elimination of the toxicity of oligomeric Aβ42, were not always directly correlated. Finally, the site(s) responsible for cytotoxicity in Aβ42 oligomers may be located in the integrated region of the N-terminal fragments of Aβ42 chains. This study provides valuable insights into the mechanisms involved in the development of natural drugs for the treatment of Alzheimer's disease. • Matrine could maintain or even enhance the cytotrophic effect of Aβ42 monomers. • Matrine could promote the disaggregation of immature Aβ42 oligomers. • Matrine could exert cytoprotective effect by making the mature Aβ42 oligomer non-toxic or inert. • The toxic site of Aβ42 oligomers might be located in the integrated N-terminal region of Aβ42 chains. [ABSTRACT FROM AUTHOR]