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Abstract: Silkworms have been developed over thousands years to optimize folding and crystallization of fibroin under highly controlled conditions which have resulted in their efficient fiber formation. In this paper, we reconstructed the three-dimensional architecture of the spinneret of a wild silkworm Samia cynthia ricini from approximately 1000 optical micrographs of the semi-thin cross sections. The chitin plates and muscles were observed in the silk press part together with large change in the diameter of the spinneret lumen at the press part by large shear stress. This is similar to the case of the spinneret of Bombyx mori silkworm, indicating that the structural change in the silk fibroin of S.c. ricini silkworm occurs exclusively at the silk press part due to large shear stresses. Molecular dynamics (MD) calculations were then performed to study the structural change that occurs in the crystalline region of S.c. ricini silk fibroin under shear stress. Namely, using the peptide AGGAGG(A)12GGAGAG as a model of the crystalline part of the silk fibroin under different shear stresses in the presence of water molecules and followed by molecular mechanics (MM) calculation after removal of water molecules. The simulation indicates that the Ala residues in the model peptides adopt a predominantly β-sheet structure under shear stresses of above 1.0GPa. [Copyright &y& Elsevier]

[Display omitted] • Shish-kebab (SK) structures grown on PLA/PAN@PLA/PVDF Janus membranes. • SK structure improves hydrophobicity of the PLA-based electrospinning membranes. • Janus-SK membrane simultaneously enhances water transport rate and interfacial binding. • SK structure promotes efficient oil-water separation. Janus membranes are widely used in fields such as oil-water separation and wound dressings due to their asymmetric wetting properties. However, the weak interface binding force between the hydrophobic and hydrophilic layers can affect the liquid transport performance and membrane separation. In this study, we have reported a method using self-induced crystallization to grow shish-kebab (SK) structures in electrospinning polylactic acid-based fiber membranes. Peel testing revealed that the peel load after induced crystallization increased from 0 to 0.05 N to 0.05–0.15 N, and the time for droplets to penetrate from the hydrophobic side to the hydrophilic side decreased from 16S to 3S. This indicates that SK structures can enhance the adhesion between the hydrophilic and hydrophobic interface, as well as facilitating droplet transport. Through the oil-water separation experiment, it was discovered that the presence of SK structures can filter out more microemulsions. For different emulsions (kerosene, petroleum, n-hexane, petroleum ether, tea tree oil), the separation efficiency of Janus-SK membrane increased by 1.67 %, 2.5 %, 3.0 %, 9.7 %, 4.3 %, respectively. The development of Janus membranes has been provided with a new direction. [ABSTRACT FROM AUTHOR]

Ternary nanocomposites including cellulose nanocrystals/silver nanohybrids (CNC-Ag) and biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were prepared by using solution casting. The effect of different AgNPs contents in the nanohybrids on crystallization ability and properties of PHBV was comprehensively investigated. Compared to binary PHBV/CNC nanocomposite, the ternary nanocomposites with high AgNPs contents showed larger improvements in the thermal stability, mechanical, barrier, overall migration and antibacterial properties. The property transitions at various AgNPs contents were due to transition of the nanohybrids induced PHBV crystallization ability (from single CNC nucleation to synergistic nucleation of CNC and AgNPs), and increased crystallinity without compromising the amounts of hydrogen bonds. Especially, the PHBV/CNC-Ag-1.7 showed the good barrier property and lower migration levels in food simulants, high antibacterial ratio of 99.9% and biocompatibility to human MG-63 cells, suggesting its potential application in food packaging related materials. [ABSTRACT FROM AUTHOR]

Most amino acid molecules have good water solubility and are rich in functional groups, which makes them a promising derivatizing agent for cellulose. However, self-condensation of amino acids and low reaction efficiency always happen during esterification. Here, amino acid hydrochloride ([AA]Cl) is selected as raw material to synthesize cellulose amino acid ester (CAE). Based on TG-MS coupling technology, a significantly faster reaction rate of [AA]Cl compared to raw amino acid can be observed visually. CAE with the degree of substitution 0.412–0.516 is facilely synthesized under 130–170 °C for 10–50 min. Moreover, the effects of amounts of [AA]Cl agent, temperature, and time on the esterification are studied. The CAE can be well dissolved in 7 wt% NaOH aq., resulting in a 7.5 wt% dope. The rheological test of the dope demonstrated a shear-thinning behavior for Newtonian-like fluid, and a high gel temperature (41.7 °C). Further, the synthesized products show distinct antibacterial activity and the bacteriostatic reduction rate against E. coli can reach 99.5 %. This work presents a new method for cellulose esterification using amino acid hydrochlorides ([AA]Cl). [AA]Cl were well adsorbed to cotton pulp through dipping, and esterification facilely occurred by heating their mixture. No protective agent was added and self-condensation side reaction was avoided. In particular, the online TG-MS instrument visually demonstrated a significantly increased esterification rate. The result of cellulose ester showed good solubility in dilute alkaline solution and antibacterial activity. [Display omitted] • A derivatization method of cellulose using amino acid hydrochloride is presented. • TG-MS test demonstrates a significantly increased reaction rate of the method. • Rheological tests prove that modified cellulose can be dissolved in NaOH aq. • The resulted products show distinct antibacterial activity after derivatization. [ABSTRACT FROM AUTHOR]

[Display omitted] • LDO/vinasse biochar composite was synthesized for phosphate recovery and reuse. • LDO@BC 0.1 exhibits an ultra-high specific surface area of 508.97 m2/g. • LDO@BC 0.1 displays excellent removal capacity for trace phosphate. • P-adsorbed LDO@BC can be used as fertilizer to accelerate plant growth. In this work, CaMgAl-layered double oxide/biochar (LDO@BC) composites were elaborated by hydrothermal coprecipitation and calcination for the efficient recovery of phosphate as well as the further application of the reclaimed composites as fertilizers. On the one hand, the appropriate selection of biochar derived from vinasses as the substrates could solve the limitations of LDO like low specific surface areas as well as poor dispersion. The obtained composites possess the ultrahigh specific surface area as high as 508.97 m2/g. Therefore, a maximum adsorption capacity of 153.64 mg/g is achieved. In addition, our composites are with fast adsorption rates that nearly 100 % phosphate could be removed within 60 s at a trace concentration owing to the large specific surface areas. On the other hand, the recovered adsorbents could be used as fertilizers because of the high contents of P, Ca and Mg elements. The phosphate-adsorbed LDO@BC (P-LDO@BC) demonstrated a positive fertilization effect, significantly accelerating plant growth with length increment by 0.75 times and mass increment by 2.09 times compared with the control groups. Thus, this work not only provides a new approach for waste vinasse utilization, but also presents a promising adsorbing material for phosphate recovery and reuse. [ABSTRACT FROM AUTHOR]

Positively charged and non-toxic intermediate layers are highly desirable for the construction of nanofiltration membranes in the field of Mg2+/Li+ separation. Herein, we have prepared dual-electric layer nanofiltration membranes via introducing positively charged quaternized cellulose nanocrystals (Q-CNC) beyond the negatively charged polyamide skin layers. On the one hand, the strong interactions between Q-CNC and piperazine (PIP) could regulate the thickness, roughness, and residual groups of the polyamide (PA) layers, resulting in improved water flux. On the other hand, the Q-CNC has lots of positive charges which are beneficial for enhancing the rejections of negatively charged polyamide skin layers towards divalent cations since the Donnan and electrostatic effects are long-range forces. Moreover, this effect could be amplified by reducing the thickness of skin layers or decreasing the contents of residual carboxyl groups via adjusting the monomer concentrations. The obtained nanofiltration membranes possess high water flux of 51 L/m2/h/bar, and rejection for MgCl 2 of 86 %. The separation factor of Mg2+/Li+ is 29 when the Mg2+/Li+ mass ratio in the feed solution is 20:1. Moreover, the nanofiltration membrane with Q-CNC intermediate layers (QNFM) has good antibacterial properties, showing great potential in the fields of lithium extraction from salt lakes. [Display omitted] [ABSTRACT FROM AUTHOR]

Novel in-situ freeze polymerization assisted layer-by-layer self-assembly method was used to prepare robust regenerated cellulose fiber-polypyrrole (RCF-PPy) composite fibers with high-conductivity, where transverse-longitudinal polypyrrole growth on RCF was regulated by using Lewis acid FeCl 3 in crystalline ice state with the template etching and oxidation effects. [Display omitted] • In-situ freeze polymerization assisted layer-by-layer assembly achieved high-conductivity composite fibers. • Modulate transverse-longitudinal PPy growth on RCF was regulated by FeCl 3 in crystalline ice state. • RCF-PPy3 formed continuous and stable conductive networks using low concentrations PPy. • RCF-PPy3 displayed high strength and exceptional durability. • RCF-PPy3 sensor was designed into various multifunctional intelligent textiles. Novel in-situ freeze polymerization assisted layer-by-layer self-assembly method was utilized to prepare robust regenerated cellulose fiber-polypyrrole (RCF-PPy) composite fibers with high-conductivity, where transverse-longitudinal polypyrrole growth on RCF was regulated by using Lewis acid FeCl 3 in crystalline ice state with the template etching and oxidation effects. The RCF-PPy3 exhibited high strength (1.01 cN/dtex) and exceptional durability, withstanding mechanical deformation, friction (100 cycles), and ultrasonic washing (50 times), addressing the issues of poor interface adhesion and conductivity stability of conductive fibers. Furthermore, the composite fiber demonstrated high electrical conductivity of 87.66 mS cm−1 and outstanding sensing performances for monitoring strain, pressure, temperature (0.34 %/°C), and humidity (0.895 %/RH). Based on RCF-PPy3, a pressure sensor was constructed as a human–machine interface electronic device, achieving sedentary reminders, fingertip information transmission, indicating great potential applications in intelligent wearable fiber electronic devices. [ABSTRACT FROM AUTHOR]

Our photocatalyst possesses homo/heterojunction structure, which consists of hexagonal CdS, cubic CdS and Prussian blue. This design of homo/heterojunction structure not only achieves ideal energy band structure, which makes for stable and rapid separation of photogenerated electrons-holes, but also improves stability of photocatalyst in various extreme circumstances. Therefore, the photocatalytic activity is significantly enhanced. [Display omitted] • The homo/heterojunctions structures were designed via one-pot kinetic regulation. • The rational energy band distribution enhances photocatalytic activity. • The strong chelation between cyanogroups and Cd2+ improve the stability. • The photocatalysts possess excellent reusability. Photoreduction of soluble U(VI) to insoluble U(IV) by CdS-based catalysts shows great potential in remediating radioactive wastewater in terms of environmental friendliness and desirable bandgap as well as the availability of CdS, but is still limited by undesirable efficiency and stability from photogenerated carrier recombination and photocorrosion. Herein, we have elegantly designed tailor-made CdS@Prussian blue with homo/heterojunctions via one-pot kinetic regulation. The key to such a structure is to leverage the outstanding binding affinity between cyanogroups of Prussian blue and Cd2+ to create diversity of local precursor concentration differences. With such unique structure and rational energy band distribution, our photocatalysts demonstrate an unprecedented U(VI) removal efficiency as high as 2.5 times that of the pristine CdS. More importantly, the strong chelation between cyanogroups and Cd2+ endows our catalysts with extremely excellent stability compared with other state-of-the-art composite photocatalysts. This work provides a facile and universal inspiration for homo/heterojunction engineering of high-performance photocatalysts for photoreduction of uranium. [ABSTRACT FROM AUTHOR]

Electric-field driven uranium extraction from seawater has been proved to greatly enhance the performances of various adsorbents via gathering uranyl ions at the surfaces, but high-concentration interfering cations would also be enriched which generates shielding effects to reduce adsorption capacity. To address this issue, we have fabricated nanofiltration membranes with sieving-adsorption properties by choosing polyamidoxime (PAO) as substrates and polyamide as skin layers. On the one hand, the polyamide skin layers fabricated by interfacial polymerization could effectively separate uranyl ions from other metal ions according to the size-sieving effect since the size of uranyl ions is much larger than most interfering cations. The results demonstrated that the nanofiltration membranes could nearly 100 % reject uranyl ions while the rejections of other metal ions below 30 %. On the other hand, the rejected uranyl ions would be enriched at the surfaces of PAO substrates and followed by adsorption. The increased uranium concentrations are beneficial for both adsorption capacity as well as adsorption rate. Therefore, the adsorption capacity increased by 30 % compared with the pristine PAO adsorbents. This work not only provides a new strategy for the design of high-performance adsorbents, but also could promote the engineering process of uranium extraction from seawater which has an important scientific significance and application value. [Display omitted] • Nanofiltration membrane with sieving and adsorption properties is prepared. • Electric fields are beneficial for the gathering of uranium at membrane surfaces. • The NF membranes could separate uranium from interfering metal ions. • The adsorption capacity of NF membrane increased by 154 % compared with the pristine PAO adsorbent. [ABSTRACT FROM AUTHOR]

The development of sustainable bio-polyurethanes (bio-PU) from nonfood lignin has been attracting extensive attention owing to the abundant reserves, stable aromatic structures, and rich hydroxyls of lignin. However, exploiting a high-performance lignin-based PU integrating excellent mechanical properties with reprocessability is still a challenge. Herein, we proposed a dynamic phenolic-carbamates to construct robust and reprocessable bio-PU elastomers based on the reaction of phenolic lignin (PL) with isocyanate. Benefiting from the low M w of 1692 Da and the abundant phenolic hydroxyls of 8.3 mmol/g, the adaptable cross-linking network consisting of dynamic hydrogen bonds and phenolic-carbamates were formed by PL. The synthesized phenolic lignin-based PU (PLPU) displayed tunable mechanical properties via adjusting PL substitution amount. The tensile strength, modulus and toughness of PLPU reached 58.8 MPa, 1350.3 MPa, and 57 MJ/m3 when the substitution amount of PL was 70%, respectively. Importantly, the reversible cross-linking structure endowed PLPU with excellent multi-reprocessability. After 5 reprocessing cycles, the retention ratio of strength, breaking elongation, modulus and toughness was 87.6%, 58.9%, 218.1% and 63.3%, respectively, which were 1.6, 1.1, 3.5, 2.2 times higher than those of commercial lignin-based polyurethane (CLPU). Therefore, this work not only presents a robust and multi-reprocessable lignin-based PU elastomer with high substitution amount, but also provides a promising sustainable alternative to replace petroleum-based plastic. [Display omitted] • Obtaining high reactive phenolic lignin with high Ph-OH content of 8.3 mmol/g. • Building dynamic H-bonds and phenolic-carbamate bonds with phenolic lignin. • Reversible crosslinks endowed PLPU with excellent mechanical and thermoplastic properties. • Maintaining 87.6% of strength after 5 remodeling cycles. [ABSTRACT FROM AUTHOR]

A new solid-state NMR experimental equipment was developed to monitor the structural change of polymer and protein fibers under active uniaxial deformation. The equipment was applied to monitoring change in the structure of a biodegradable aliphatic polyester fiber, poly(tetramethylene succinate) (PTMS; [–O(CH 2 ) 4 OCO–(CH 2 ) 2 CO–] n ), as a function of tensile stress. The crystal transition from α to β forms for PTMS was induced by stress and monitored by the change of the methylene region in the 13 C NMR spectra. The 13 C chemical shielding constant for the model compound of poly(tetramethylene succinate) was calculated using the GIAO–CHF (gauge invariant atomic orbitals–coupled Hartree–Fock) with ab initio 6-311G ∗∗ basis set. This calculation acceptably explains the experimental results. [ABSTRACT FROM AUTHOR]

Green and sustainable cellulose aerogels have attracted extensive attention, but are severely limited by unsatisfied elasticity, fatigue resistance as well as fire hazard for functional applications. Herein, we proposed a novel and feasible strategy to fabricate highly elastic, thermal insulating and fireproof phytic acid/cellulose (PA/CE) aerogel via constructing microfilament substructure derived from PA-induced aggregation and assembly of cellulose chains. Benefiting from the interconnected fibrous cellular walls integrating with abundant microfilaments, the resultant PA/CE aerogels demonstrated excellent compressibility and resilience with recovery rate of 91.26% after 100 compressive cycles at 50% strain. With the hierarchical porous structure, PA/CE aerogels exhibited low thermal conductivity of 0.0340–0.0352 W/m·K, could maintain its structural integrity and high temperature thermal insulation after heat treatment for 30 min at 400 ℃. Moreover, the integration of PA enabled aerogel high fireproofing with limiting oxygen index (LOI) of 42.6% and UL-94 V-0 rating. The peak of heat release rate (PHRR) and total heat release (THR) of PA/CE aerogels were 79.97 kW/m2 and 1.75 MJ/m2, reduction by 43.0% and 46.5% compared with cellulose aerogels. Thus, the elastic cellulose aerogels proposed by this strategy provide an insight and feasibility for high performance and multifunctional applications. [Display omitted] • PA-induced aggregation and assembly of cellulose chains was proposed. • The resulting PA/CE aerogels had hierarchical porous structure with plentiful microfilament substructures. • The aerogels displayed excellent compressibility and fatigue resistance with recovery rate of 91.26% after 100 compressive cycles. • The aerogels possessed high temperature thermal insulation with structural integrity bearing heat treatment at 400 ℃ for 30 min. • The aerogels showed high fireproofing with 43.0% and 46.5% reduction of PHRR and THR compared with CE aerogels. [ABSTRACT FROM AUTHOR]

The properties of polyglycolide (PGA) fibers used as surgical sutures depend on their aggregated state structure. The study investigated the relationship between the structural evolution and macroscopic properties of PGA fibers with low-crystallinity under coupled stress-temperature fields by conducting in-situ WAXD/SAXS, DSC and SEM measurements. The WAXD and SAXS results indicated that the structural evolution during the low-temperature stretching stage primarily relied on stress-induced amorphous molecular chain orientation and the formation of small crystals. The DSC results confirmed that uniaxial stretching enhanced the orientation of amorphous molecular chains, leading to cold crystallization of PGA fibers at lower temperatures. During the heating stretching stage at temperatures of 60–90 °C, numerous crystals were generated through a lamellar insertion mechanism and underwent lateral growth. This is reflected by the crystallinity, crystal orientation, and crystallite sizes increased significantly, while the long period decreased rapidly. The high-temperature stretching stage resulted in fragmentation and recrystallization of lamellar crystals, forming fibrous crystals. Stretching at 110 °C exhibited higher Iq 2 /Iq 1 values than other temperatures, which means that 110 °C is more favorable for the formation of fibrous crystals. Additionally, PGA fibers stretched at 150 °C exhibited the highest crystallinity and crystal orientation, which led to a 440 % increase in tensile strength. Its resistance to degradation has also been significantly improved compared to the original fibers. [Display omitted] • Low-crystallinity PGA fibers were stretched during variable temperature. • The stress and temperature fields dominated the structural evolution in different stretching stages. • Hot stretching improved the mechanical properties and resistance to degradation of PGA fibers. [ABSTRACT FROM AUTHOR]

[Display omitted] • LZO-modified NCM811 is prepared via sol–gel coating and annealing methods. • Influence of annealing temperatures systematically studied. • The 750 °C annealed sample shows best electrochemical performances. • Optimized annealing procedure enhances microstructural stability and alleviates cation mixing. Li 2 ZrO 3 (LZO) coating has been routinely applied on Ni-rich NCM cathode materials via two-step processes to improve their electrochemical performances, but procedures for sample preparation remain elusive. Ni-rich NCM materials are particularly sensitive to temperatures, but annealing temperatures show random variation between 400 and 850 °C in literatures. In this work, the influence of annealing temperature on microstructures and electrochemical properties are systematically studied for the LZO-modified NCM811. It is found that, a thicker LZO coating with amorphous features can be obtained at a lower annealing temperature; but the LZO is fully dissolved into the crystal lattice of NCM811 at a higher temperature. The best electrochemical performance is achieved at the condition of 750 °C, because an optimized annealing temperature can introduce moderate Zr4+ doping and obtain high-quality coating layers. This work offers a guidance for industrial to enhance electrochemical performances of Ni-rich NCM cathode materials during surface modification processes. [ABSTRACT FROM AUTHOR]

Mechanically twisting a yarn is a useful and important method for creating internal stress, changing macromolecular orientation, and affording interesting fiber properties, including mechanical, structural, physical and chemical properties. Bacterial cellulose (BC) nanofibers are a new type of highly crystalline bionanofibers exhibiting excellent intrinsic mechanical properties. Herein, BC macrofibers with a diameter of 0.35–0.53 mm were prepared from BC hydrogel films using a two-step technique involving drying and twisting processes. Moreover, the effects of the drying method (oven- and freeze-drying) and those of the processing steps on the morphologies, structures, and physicochemical properties of the macrofibers were investigated. Results indicated that only the wet twisting–first process affords continuous macrofibers with a compact and uniform structure. The tensile strength and elongation at break of the macrofibers were 199 MPa and 24%, respectively. Furthermore, by introducing graphene oxide (GO) to the macrofibers, a photothermal and moisture actuator was facilely constructed, which could produce a twisting motion of 0.39 rpm and an untwisting motion of 0.6 rpm. This study provides insights into methods to easily alter the properties of BC macrofibers, which is pivotal for the macrofiber's potential application in intelligent devices. [Display omitted] • The surface of T-OD macrofibers is smooth and flat, and the tensile stress can reach 199 MPa. • The GO-T-OD macrofiber can produce reversible motion under moisture and NIR light stimulation, and the rotation angle can be increased to 121°/cm in 25 s • Reversible twisting artificial muscles offer unlimited possibilities for future applications in artificial muscles and other intelligent drives. [ABSTRACT FROM AUTHOR]

Fiber-based wearable electronic textiles have broad applications, but non-degradable substrates may contribute to electronic waste. The application of cellulose-based composite fibers as e-textiles is hindered by the lack of fast and effective preparation methods. Here, we fabricated polyaniline (PANI)/cellulose fibers (PC) with a unique skin-core structure through a wet-spinning homogeneous blended system. The conductive network formation was enabled at a mere 1 wt% PANI. Notably, PC15 (15 wt% PANI) shows higher electrical conductivity of 21.50 mS cm−1. Further, PC15 exhibits excellent ammonia sensing performance with a sensitivity of 2.49 %/ppm and a low limit of detection (LOD) of 0.6 ppm. Cellulose-based composite fibers in this work demonstrate good gas sensing and anti-static properties as potential devices for smart e-textiles. [Display omitted] [ABSTRACT FROM AUTHOR]

Many gel-like soft composites were obtained by using thermoplastic polyurethane (TPU) as the matrix in this work. Different contents of plasticizer dibutyl adipate (DBA) was added to TPU to swell its molecular chains and allowed them to pass through each other easily. These samples were then sandwiched between two electrodes as actuators and their actuation abilities were investigated. The results showed that the largest deflection among those samples was up to 12.11 mm, which corresponds to 48.44% of the length of samples (at 2.86 V μm−1). The deflection increased with increasing of the electric field intensity. Besides, the actuator was able to promptly respond to the change of voltage within 0.12 s. A wide response ability in the frequency region from 0.5 Hz to 10 Hz was confirmed, and the largest amplitude over 22 mm of the actuator was observed at 5 Hz. Furthermore, a new method was proposed in this paper to estimate the tiny force generated by the actuator. The small variation (less than 3%) of the measured results indicated that the proposed method is reliable even at a small bending angle. It is believed that the rapid bending capability and large deformation of the developed actuator at low intensity of electric field will make its considerable contributions to the field of soft robotics or biomaterials. Image 1 • Plasticized gel based actuators were prepared and their properties were investigated. • The largest actuating deflection was up to 48.44% of the sample length at 2.86 V μm−1 • The actuation behaviors in an electric field is a consequence of multiple factors. • A new method was proposed to estimate the tiny actuation force. [ABSTRACT FROM AUTHOR]

Double stimuli-responsive functionalized cellulose nanocrystal-poly[2-(dimethylamino)ethyl methacrylate] (CNC- g -PDMAEMA) reinforced poly(3-hydroxybutyrate- co -3-hydroxy valerate) (PHBV) electrospun composite membranes were explored as drug delivery vehicles using tetracycline hydrochloride (TH) as a model drug. It was found that rigid CNC- g -PDMAEMA nanoparticles enhanced thermal, crystallization and hydrophilic properties of PHBV. Moreover, great improvements in fiber diameter uniformity, crystallization ability and maximum decomposition temperature (T max) could be achieved at 6 wt% CNC- g -PDMAEMA. Furthermore, by introducing stimuli-responsive CNC- g -PDMAEMA nanofillers, intelligent and long-term sustained release behavior of composite membranes could be achieved. The releasing mechanism of composite membranes based on zero order, first order, Higuchi and Korsmeyere-Peppas mathematical models was clearly demonstrated, giving effective technical guidance for practical drug delivery systems. Electrospun PHBV composites membrane with double stimuli-responsive cellulose nanocrystal tailor drug release at human physiological condition for long-term sustained drug delivery. Unlabelled Image • Functionalized cellulose nanocrystals gave double stimuli-responsive performance. • Composite membrane has intelligent drug release ability at human physiological condition. • Composite membrane shows faster drug rate at pH = 5 for potential tumor cell targeting. • Four releasing mechanism of composite membranes have been clearly demonstrated. [ABSTRACT FROM AUTHOR]

• Novel fabrication of dipeptide and curcumin onto the silk protein hydrogel dressing. • Designed materials have promising cell compatibility and effective bacterial inhibition. • Metal chelating L-carnosine has greatly influencing the inactivation of MMP-9. • This hydrogel dressing could be accelerate therapeutic potential of diabetic wound healing. The infected diabetic wound ulcer is a significant problem for the diabetic patients, which leads to removal of affected foot site due to its delayed/non-healing tissues. The poly-microbial infections and active matrix metalloproteinases (MMP) are the significant influencing factors to delayed healing in diabetic mice. The main purposes of present investigation are to evaluation the targeted inactivation of MMP and avoid polymicrobial infections by using a combined therapeutic effect of metal chelating dipeptide (L-carnosine) and curcumin with the biocompatible silk protein hydrogel (L-car@cur/SF) dressing in the infected diabetic wound ulcer. The in vitro biological assay methods, such as, cell viability, anti-oxidant activity, anti-inflammatory macrophage cells and inhibition collagenase exhibited that the designed hydrogel matrix to be human cell compatible and could be accelerate for significant diabetic healing potential. The activation of cur/SF matrix by the L-carnosine was persuading the inactivation of matrix metalloproteinase-9 (MMP-9) through its potent chelating effects of Zn2+ ions from the MMP-9 active center. The L-car@cur/SF hydrogel was demonstrated for the effective MMP-9 inactivation and bacterial inhibition via in vivo mice wound site, which indorsed the diabetic wound healing efficiency in streptozotocin-tempted diabetic mice. [ABSTRACT FROM AUTHOR]

• Solvent free technology is applied in the polymerization of MEPCM. • The MEPCM possess high latent heat, good thermal stability and high thermal conductivity. • The mechanism of the interfacial polymerization is revealed by in situ component analysis. A kind of eco-friendly micro-encapsulated phase change materials (MEPCM) with dodecanol dodecanoate as core material were synthesized via the interfacial polymerization of toluene-2, 4-diisocyanate (TDI) and diethylenetriamine (DETA). During the preparation, a facile solvent free synthesis route was developed owing to the good compatibility of TDI and dodecanol dodecanoate. The synthesized MEPCM were characterized by Field Emission Scanning Electron Microscopy (FE-SEM), Particle Size Distribution (PSD) analyzer, Differential Scanning Calorimetry (DSC), Thermogravimetric/Infrared spectrometry (TG-IR) and thermal constants analyzer. It is found that the resultant MEPCM in nearly spherical shape are in the size scope from 10.0 to 40.0 μm, have the average latent heat in the range of 103.4–140.3 J/g, and exhibit high temperature resistance with an onset evaporation temperature at 234.0 °C. Moreover, the MEPCM possess good thermal conductivity from 0.17 W/m K to 0.21 W/m K. Therefore, it is confirmed that the prepared MEPCM can be regarded as a promising thermal energy storage material appropriate to the thermo-regulating fields such as renewable solar heating system. [ABSTRACT FROM AUTHOR]

Blending of plant-based cellulose and marine-derived chitosan in micro-level has potential to make fascinating materials. However, this task is frequently hindered by the poor solubility of the polysaccharides. Here, using a green alkali/urea solvent media together with a well-designed dissolving strategy, original cellulose pulp and chitosan power were dispersed into a homogeneous solution. Driven by the intermolecular hydrogen-bond interaction, cellulose and chitosan chains were facially self-assembled into a unique 3D alloy structure. Owing to the rich interface interactions, the tensile strength and breaking elongation of the alloy film increased by 69% and 260%, respectively, when compared to a pure chitosan film. Besides, the 3D alloy films with a pore diameter of 920–1435 nm exhibited an extremely high cell viability which was higher than 95%. Additionally, accelerated wound healing rate of 95.6% reached in the presence of the alloy film after two weeks using a full-thickness wound in a rat model. Unlabelled Image • Chitosan and cellulose were co-dissolved into one green alkali/urea solvent. • Polysaccharide chains were self-assembled into 3D porous alloy films. • Abundant interface interactions led to excellent physicochemical properties. • Biocompatibility and bioactivity of the alloy result in good wound healing. [ABSTRACT FROM AUTHOR]

Nanostructured materials with designable microstructure fabricated through a facile and green method are highly desired for practical applications in nanotechnology. Herein, without using any toxic reagents, flexible cellulose aerogel nanocomposites embedded with ZnO@noble metal nanoparticles (NPs) were successfully prepared from a cellulose dope. Morphology, structure, and mechanical properties of the nanocomposite were characterized. Flower-liker ZnO particles were synthesized through cellulose mineralization and it acted as a platform for efficient photocatalytic synthesis of noble metal (Ag, Au, Ag-Au) NPs. The noble metal NPs were well dispersed in the three-dimensional (3D) cellulose skeleton, resulting in abundant "hot spots" for high Surface Enhanced Raman Scattering (SERS) signal enhancement. Using rhodamine 6 G (R6G) molecules as probe molecules, the detection limits and calculated enhancement factors approached to 10−10 M and 4.8 × 107, respectively. Particularly, the photocatalytic capabilities of noble metal-semiconductor heterostructure embedded in porous aerogel made it a self-cleaned SERS substrate. There was little sensitivity loss after recycling use for 3 times. This work presented a sustainable and cost-reduction strategy to construct sensitive SERS substrate. [Display omitted] • Cellulose aerogel embedded with ZnO@Ag/Au is facilely fabricated from a dope. • The actived celluloe chains act as mineralization template for flower-like ZnO. • Ag/Au NPs are plated to ZnO surface through a controllable photoreduction method. • 3D porous aerogel gives anchoring effect for particles and bring abundant "hot spots". • Hierarchical nanostructures achieves a flexible, sensitive and reusable SERS strips. [ABSTRACT FROM AUTHOR]

Highlights • A facile method of loading metal-organic frameworks (MOFs) onto cellulose aerogels (CA) is developed. • The equilibrium adsorption capacity of Pb2+ adsorbed by UiO-66-NH 2 @CA was 89.40 mg g−1. • The complete decomposition temperature of UiO-66-NH 2 @CA was increased by 62.1 ℃ compared with CA. • The hybrid aerogels could be recycled without secondary pollution. Abstract In the present work, we develop novel method of loading metal-organic frameworks (UiO-66 and UiO-66-NH 2) on the flexible cellulose aerogels as metal-organic frameworks@cellulose aerogels composite materials by using in situ growth procedure at room temperature. The as prepared metal-organic frameworks@cellulose aerogels composite materials were well characterized via SEM, XRD, atomic absorption spectrometer, and TG analysis, besides the adsorption of Pb2+ and Cu2+ in metal-organic frameworks@cellulose aerogels composite materials was investigated. The amount of metal ions adsorbed by metal-organic frameworks@cellulose aerogels composite materials is equal to the sum of metal-organic frameworks and cellulose aerogels, indicating that the metal-organic frameworks are not blocked after cellulose aerogels growth and still have adsorption properties. It was found that metal-organic frameworks@cellulose aerogels composite materials can be recycled to adsorb Pb2+ and Cu2+ in water after simple cleaning. The equilibrium adsorption capacity of Pb2+ adsorbed by UiO-66-NH 2 @CA was 89.40 mg g−1, and can be easily reused for more than 5 cycles without significant decrease in performance. Moreover, the maximum decomposition temperature (T max) of UiO-66-NH 2 @CA was increased by 62.1℃. This result suggested that such metal-organic frameworks@cellulose aerogels composite materials could adsorb heavy metal ions in water could by avoiding secondary pollution and show great potential in water treatment. [ABSTRACT FROM AUTHOR]

A novel chemical reduction method was reported to prepare tunable spherical or belted morphologies of nano-selenium (Se) based on cellulose nanocrystal (CNC). The homogeneous Se nanospheres with size of about 36 nm can be found for Se-Sphere-12H by adding ascorbic acid (VC) as assisted reducing agent. The Se nanobelt with a length of about 800 nm can be observed for Se-Belt-12H through one-pot reaction of CNC with sodium selenite (Na 2 SeO 3 ) under hydrothermal conditions. Moreover, Se-Belt-12H exhibited the higher crystallinity of 96.10% and maximum thermal degradation temperature (T max ) of 479.4 °C, the highest capacitance and the smallest internal resistance. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) as catalysts for the activation of peroxymonosulfate (PMS) to remove recalcitrant organic contaminants has been well reported, however, the separation of MOFs from the solution is difficult because of their powder state, which limits their applications. In the present study, zeolitic imidazole framework (ZIF) materials, ZIF-9 and ZIF-12 were pioneered to load on cellulose aerogels, and the hybrid aerogels as metal catalysts to effectively activate PMS for Rhodamine B (RB), tetracycline hydrochloride (TC) and p-nitrophenol (PNP) degradation. The hybrid aerogels/PMS system could remove PNP about 90% in 1 h, which hard to remove from water. The pH value of the solution had no effect on the degradation process, which demonstrated that the hybrid aerogels had excellent pH tolerance. In addition, the mechanism of PNP degradation was investigated by electron paramagnetic resonance (EPR) and free radical trapping methods. The results showed that PMS could effectively activate by hybrid aerogels to produce sulfate radicals (SO 4 −), hydroxyl radicals ( OH), and revealed that SO 4 − play a key role in degradation. The most important feature of hybrid aerogels is can be easily separated from the solution. The obtained results showed that the hybrid aerogels exhibit excellent recyclability, with no significant effect on degradation. The prepared hybrid aerogels are green, environmentally friendly with high catalytic efficiency. Further, the outstanding degradation of PNP demonstrates the promising prospects of hybrid aerogels as advanced oxidation process (AOP) catalysts. [ABSTRACT FROM AUTHOR]

In this work, a novel flexible electrode material for supercapacitor is prepared by electrodeposition of Ni-Co-S interconnected nanosheet arrays on N-doped hierarchical porous carbon nanofibers (Ni-Co-S@N-pCNFs). The electrode exhibits a remarkable specific capacitance of 520.2 F g -1  at the current density of 0.2 A g −1 and 670 F g -1  at 2 mV s −1 . The activated charcoal (AC) loaded N-doped porous carbon nanofibers (AC@N-pCNFs) as electrode is also prepared which exhibits a specific capacitance of 257.2 F g -1  at 0.2 A g −1 , as well as excellent cycling stability with a capacitance retention of 92.6% after 5000 cycles. Furthermore, the Ni-Co-S@N-pCNFs as the positive electrode, active carbon loaded N-doped hierarchical porous carbon nanofibers (AC@N-pCNFs) as negative electrode, and KOH/NKK hybrids as both the electrolyte and separator are assembled into flexible asymmetric supercapacitor. The assembled supercapacitor device without using any current collectors or binders shows a high energy density of 21.6 Wh·kg −1 at a power density of 134.9 W kg −1 and robust long-term cycling stability retaining over 90.0% after 3000 cycles at 1.0 A g −1 . The as-assembled asymmetric supercapacitors (ASCs) have an outstanding mechanical flexibility and electrochemical stability and no significant attenuation occurred during cycling under different bending states. [ABSTRACT FROM AUTHOR]

Abstract The defects of polysulfide dissolution and sulfur insulating causes in Li-sulfur batteries have effectively diminished by immobilizing sulfur in porous carbon microspheres via the interactions of doping-nitrogen and encapsulating-reduced graphene. The nitrogen-rich porous carbon microspheres were prepared by using yeast as natural precursor and high content of nitrogen (up to 8.52%) doped carbon microspheres was confirmed by the elemental analysis. As cathode for lithium-sulfur batteries, the rGO@HYC/S composite exhibits a high retention capacity of 921 mA h g−1 at 0.2 C and 675 mA h g−1 at 1 C over 200 cycles. The battery delivers low capacity decay rate of 0.09% and stable coulombic efficiency about 98% at 1 C during the 200 cycles. Further, we reveal that the enhanced electrochemical performance is ascribed to a hollow porous structure of carbon framework for sulfur storage, carbon matrix exerted by nitrogen-doping for polysulfide adsorption, rGO wrapper for polysulfide interception and conductivity improvement. [ABSTRACT FROM AUTHOR]

Nowadays, photothermal agents have attained considerable attention in nanomedicine for the treatment of cancer after chemotherapy, surgery, biological therapy and radiotherapy. In this work, we showed a sericin-based, simple approach for synthesis of sericin functionalized reduced graphene oxide (SRGO) with low cytotoxicity and photo thermal efficiency. During the synthesis, the GO is deoxygenated in situ and functionalized by sericin, a low-cost, silk protein and concurrently forms SRGO. The subsequent SRGO disperse well in water with higher biocompatibility because of the decoration of sericin on graphene sheets. The prepared SRGO exhibited a good photothermal capacity with near-infrared laser irradiation (808 nm) for efficient killing of HeLa cells. Further, the synthesized SRGO could act as a promising material for photo thermal therapy applications in future. [ABSTRACT FROM AUTHOR]

The construction of high performance ionic conductive hydrogel together with strength, toughness, transparency, environment tolerance, stable conductivity and response is still an urgent demand in flexible sensing field. Here, a simple and feasible strategy was proposed to produce ionic conductive hydrogels by integrating polyvinyl alcohol (PVA)/silk sericin (SS) with sodium citrate (Na 3 Cit) in glycerol (Gl)/water solution. The synergistic action of physical cross-linked polymer networks and supra-molecular interactions enabled the resultant PVA/SS/Na 3 Cit/Gl hydrogels with super strong (7.56 MPa), tough (39.37 MJ/M3), stretchable (787.96%) and transparent (90%). Especially, the PVA/SS/Na 3 Cit/Gl hydrogels displayed excellent extreme temperature tolerance, retaining highly stretchability (> 500% strain), strong (7–12 MPa) and tough (25–52 MJ/M3) at −25 to 60 °C or 7 d storage at 30 °C. Profiting from these advantageous performances, PVA/SS/Na 3 Cit/Gl hydrogels could be assembled as transparent flexible sensors to quickly and precisely response human activities with a wide strain range (up to 200% strain), excellent stability and repeatability even at −25 °C or 7 d storage. In addition, PVA/SS/Na 3 Cit/Gl hydrogels showed cytocompatibility with good cell proliferation of Cos 7 fibroblasts within 72 h incubation. Thus, the presented PVA/SS/Na 3 Cit/Gl hydrogels suggested a promising prospect as reliable wearable electronics adapting to mechanical and environmental durability. [Display omitted] • Super tough, stretchable and transparent ionic conductive hydrogel was prepared by a simple and feasible strategy. • Physical crosslinked polymer networks and supramolecular interactions are synergistic. • Hydrogel has super strong of 7.56 MPa, tough of 39.37 MJ/M3, stretchable of 787.96%, and transparent of 90%. • Hydrogel displayed excellent temperature tolerance (−25 to 60 °C). • Hydrogel sensor precisely and stably response human motions at −25 °C or 7 d storage at 30 °C. [ABSTRACT FROM AUTHOR]

This work presents a facile and practical preparation method of cellulose-based bioadsorbent modified by hyperbranched polyethyleneimine (hPEI) using glutaraldehyde cross-linking in heterogeneous system for various dyes removal. The grafting of hPEI with a large molecular structure was achieved efficiently according to the FTIR and XPS analysis. The adsorption properties of the cellulose-based bioadsorbent for anionic reactive yellow X-RG (XRG), cationic bright yellow M-7G (M7G), nonionic disperse brown S-3RL (DB 3) were explored. The kinetics curve was well fitted with pseudo-second-order model, and the equilibrium data well suited Langmuir model with maximum adsorption capacity of 571.43 mg g −1 for M7G, 581.40 mg g −1 for DB 3 and 970.87 mg g −1 for XRG. Compared with other bioadsorbents reported previously, the cellulose-based bioadsorbent could be facilely prepared and simultaneously exhibited enhanced removal for dyes. Therefore, this work will help accelerate the study of scale production of bioadsorbent for treatment of textile effluents. [ABSTRACT FROM AUTHOR]

Flexible supercapacitors with both high energy and high power densities are critical for flexible electronics. In this paper, hybrid flexible carbon nanofibers decorated with NiCo 2 S 4 nanoparticles are successfully prepared by combination of electrospinning, carbonization and hydrothermal treatments. The obtained hybrid carbon nanofibers display remarkable specific capacitance (527.8 F g −1 at the current density of 0.2 A g −1 and 622.5 F g −1 at 2 mV s −1 ), good rate capability (310.5 F g −1 at 4.0 A g −1 ) and excellent cycle stability (retaining 90.0% after 3000 cycles). The flexible asymmetric supercapacitors based on carbon nanofibers decorated with NiCo 2 S 4 and porous carbon nanofibers coated with activated charcoal are fabricated. The combined unique properties of each of these components enable highly flexible and mechanically strong films that can serve as electrodes directly without using any current collectors or binders. The fabricated device shows an energy density of 32.1 Wh kg −1 at power density of 67.6 W kg −1 and cycle stability retaining 88.5% after 1500 cycles at 1.0 A g −1 . Therefore, the novel flexible asymmetric device with perfect flexibility and stability can be applied as one of the most promising power supplies. [ABSTRACT FROM AUTHOR]

In this study, hierarchically feather-mimetic structures formed of poly(m-phenylene isophthalamide) (PMIA) nanofibres were prepared by electrospinning and subsequent crystallisation for superwettability applications. X-ray diffraction measurementsand scanning electron microscopy show that a feather-mimetic structure of crystallised nanoflakes was formed following a hydrothermal treatment process. The nanoflakes formed a nanosized fine texture on top of a coarser-textured membrane, which greatly improved the membrane roughness and yielded a hierarchical topography. After fluorination, the membrane exhibited superamphiphobicity, with surface contact angles of 151° and 136° for water and hexadecane, respectively. The method provides new insight for the design and development of functional bionic membranes based on PMIA. [ABSTRACT FROM AUTHOR]

In situ polymerization is a prominent current topic in the research of skin-core structure polyaniline (PANI) conductive fibers owing to its advantages such as the convenience of preparation and high conductivity of fiber, but it is difficult to realize the continuous fabrication of conductive fibers using this method. In our previous work, we presented a novel method based on in situ polymerization and achieved the continuous fabrication of conductive yarns. In order to reduce the consumption of raw materials such as aniline, doping acid, and oxidant in the preparation, a further improvement is proposed in this paper. Electrical conductive silk fibroin (SF) yarns covered with PANI were prepared by using an improved method based on in situ polymerization. The results show that the improved method has lower consumption than the previous method, and the reduction of raw materials can reach more than 90% compared to the previous method. The structure and properties of the treated SF yarns were studied in detail. The treated SF yarns characterized using scanning electron microscopy and Fourier transform infrared spectroscopy improved the surface of the SF fibers and the gaps between them were covered by conductive PANI; further, interactions such as van der Waals' force, electrostatic interaction, and hydrogen bonding existed between the SF macromolecules and PANI. Thermogravimetric analysis indicated that the thermal stability of the treated yarns was reduced owing to the existence of PANI. The treated yarns exhibited good conductive properties; with the increase in oxidant concentration, the conductivity of coated yarns increased first and thereafter decreased; the maximum conductivity of coated yarn could reach 60 S/m, and the maximum conductivity of PANI was as high as 180 S/m. Compared to the SF yarn, the breaking strength, breaking elongation, and initial modulus of coated yarns were reduced and the loss was increased with the increase in oxidant concentration. [ABSTRACT FROM AUTHOR]

Fabrication and characterization of bbiodegradable nanocomposites based on poly (3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) matrix reinforced with cellulose nanocrystal (CNC)-ZnO nanohybrids via simple solution casting for possible use as antibacterial biomedical materials is reported. The obtained nanocomposites exhibited an excellent antibacterial ratio of 95.2–100% for both types of bacteria namely S. aureus and E. coli and showed 9–15% degradation after one week. The addition of CNC-ZnO showed a positive effect on hydrophilicity and barrier properties. More significantly, the nanocomposites with 10 wt% CNC-ZnO showed enhancement in tensile strength (140.2%), Young’s modulus (183.1%), and the maximum decomposition temperature (T max ) value increased by 26.1 °C. Moreover, this study has provided a possible mechanism for using such nanofillers on the hydrolytic degradation of PHBV, which was beneficial to obtain the high-performance nanocomposites with modulated degradation rate for antibacterial biomaterials. [ABSTRACT FROM AUTHOR]

In this work, the flexible electrospun carbon nanofiber substrates fixed with Ag nanoparticles and graphene oxide have been prepared by combination of electrospinning and carbonization treatments. And then growth of NiCo 2 S 4 nanotube on carbon nanofibers to form hybrid carbon nanofibers was prepared by a hydrothermal method. The composition and microstructures of resultant composites were characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffractometer (XRD). The obtained hybrid carbon nanofibers exhibited excellent property of suppleness. The electrochemical activity and stability of hybrid carbon nanofibers were investigated by electrochemical measurement and it exhibited an excellent specific capacity of 360 F·g − 1 at 0.3 A·g − 1 . Notably, the specific capacity of hybrid carbon nanofibers also exhibited a remarkable cycling stability (90.0% retention after 2000 cycles). The assembled symmetric hybrid carbon nanofibers-based supercapacitor also exhibited excellent flexible, include bendable, foldable and even twistable property. [ABSTRACT FROM AUTHOR]

To improve insulin bioavailability and overcome multiple barriers for oral delivery of insulin, the composite nanocarriers (PLGA/FA-CS) prepared from poly(lactide- co -glycoside) (PLGA) and folic acid modified chitosan (FA-CS) were fabricated via electrostatic self-assembly method. The resultant composite nanocarriers exhibited low cytotoxicity against HT-29 cells and excellent stability against protein solution. The chemical stability of loaded insulin against digestive enzyme were established in presence of simulated gastric fluid (SGF) containing pepsin and simulated intestinal fluid (SIF) containing pancreatin, respectively. The uptake behavior of HT-29 cells was evaluated by confocal laser scanning microscope. After oral administration to the diabetic rats, an effective hypoglycemic effect was obtained compared with subcutaneous injection of insulin. This work suggests that the as-prepared composite nanocarriers may be a promising drug delivery system for oral administration of insulin and other biomacromolecules. [ABSTRACT FROM AUTHOR]

Due to the complexity, heterogeneity and recalcitrant structure of lignin, the extraction of multifunctional lignin directly from lignocellulose is still a challenge. Here, a green and recyclable route was proposed to separate high-quality lignin and tailor its functionalities. Through tuning the components of deep eutectic solvent (DES) and separation procedures, DES extracted lignin (DESL) exhibited high purity of 99.6 %, yield of 83.2 % and phenolic hydroxyl content of 8.33 wt%. The results of FTIR and 13C NMR demonstrated that DESL possessed more oxygen-containing reactive groups compared with commercial lignin (CL), enabling DESL with more superior functional activities. DESL exhibited higher antioxidant activity with the DPPH capture rate of 73.2 %. Meanwhile, DESL showed strong bactericidal effects against E. coli (100 %) and S. aureus (100 %) due to higher phenolic hydroxyl content, which could destroy bacterial cell membranes and inhibit bacterial metabolism by interacting with phospholipid layer and protein. Additionally, DESL displayed strong UV absorption and could be blended with polyurethane to enhance UV shielding property of polyurethane composite film with >50 of UPF value. In summary, DES treatment is a suitable strategy for high-quality lignin separation, which opens a broad spectrum of possibilities for lignin valorization. [Display omitted] • Efficient, green and recyclable strategy was proposed to extract active lignin from waste wood flour. • Obtained lignin displayed high purity, yield, and activity with Ph-OH content of 8.33 wt%. • DESL exhibited higher antioxidant activity with a DPPH capture rate of 73.2 %. • DESL could completely sterilize by destroying the cell structure of bacteria. • DESL could be added to the polymer to greatly improve its UV shielding performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • P/N/Si co-modified fabric was presented via covalent bond and electrostatic assembly. • Modified cotton fabric displayed excellent flame retardancy and self-extinguishing. • Improved washing durability was acquired with LOI of 27.1% after 50 LCs. • Smoke suppression performance was significantly improved. • Mechanical properties and moisture permeability were substantially retained. Flame retardant cotton fabric has attracted extensive attention and research with the increase of public safe awareness. However, it still remained a great challenge to balance the performances of high flame retardancy, durability, mechanical strength, as well as formaldehyde-free, comfort, green and feasible process. Herein, efficient, durable and breathable flame retardant cotton fabrics were fabricated through a one-pot approach based on a synergetic system combining phytic acid (PA) with polyethyleneimine (PEI) and 3-Glycidyloxypropyltrimethoxysilane (GPTMS). The modified cotton fabrics displayed high-efficiency fire resistance, self-extinguishing and excellent washing resistance due to the formation of surface hybrid network architectures from multiple covalent bonds (Si O C, C N, P O C) and electrostatic assembly. The limiting oxygen index (LOI) could retain at 27.1% after 50 laundering cycles (LCs). Moreover, the peak of heat release rate (PHRR), total heat release (THR) and total smoke release (TSP) declined by 85.89%, 52.72% and 47.22% compared with neat fabric, indicating boosted flame retardance and excellent smoke suppression ability. In addition, the proposed surface finishing process substantially retained the mechanical properties and moisture permeability, providing a simple and feasible approach for high-efficiency, durable and breathable flame retardant cotton fabric. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-crystal NCM111 (SC-NCM) is obtained from a ternary MOF precursor. • SC-NCM can be operated at a high cut-off voltage with good cyclability. • Specific capacity can be boosted at a large operation range of 2.8–4.6 V. • Enhanced performance can be attributed to better microstructural stability. Single-crystal NCMs show properties of good cyclability and high safety, and considers as promising cathode materials for next generation lithium batteries. But industrial production of single-crystal NCMs should overcome problems of lengthy production steps, high production costs and poor consistency. In this work, a Ni-Co-Mn ternary MOF has been developed for NCM cathode materials preparation. The MOF derived precursors show high activity and can be used to prepare single-crystal NCM111 (SC-NCM) in a regular sintering process. As-prepared SC-NCM cathode materials show an average particle size of 400 nm, reveal a polyhedral structure with smooth surface, and can be applied as a high-voltage cathode with excellent cyclability and high specific capacities. Specifically, it is delivery a high discharge capacity of 172 mAh g−1 and maintains 156 mAh g−1 after 50 cycles in a large potential range of 2.8–4.6 V at a high current of 1 C; it also reveals a good capacity retention of 88.3 % after 600 cycles. The enhanced electrochemical performance can be attributed to the SC-NCM reveals a good microstructural stability, which prevents the unexpected structural degradation and microcrack generation during battery cycling. This work provides a new method to synthesis the high-quality single-crystal NCM materials with good electrochemical performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amphoteric cellulose microsphere (ACM) contains both carboxyl and amino groups. • ACM displayed hierarchic porous network structures and high specific surface areas. • ACM could simultaneously remove both cationic and anionic dyes. • ACM could effectively treat actual dyeing wastewater. Amphoteric cellulose porous microsphere adsorbents (ACM) with high contents of functional groups were prepared by carboxylation and amination reactions. The obtained ACM possess similar contents of carboxyl groups (1.52 mmol/g) and amino groups (1.51 mmol/g). In addition, the modified microspheres exhibited excellent mechanical properties benefiting from the dense porous structures. The ACM could simultaneously remove the cationic dye methyl orange (MO) as well as the anionic dye methylene blue (MeB) with adsorption capacities as high as 345.32 mg/g and 616.12 mg/g, respectively. Another the microspheres are also with good regeneration that the adsorption capacities still maintained more than 90 % after 8 cycles. [ABSTRACT FROM AUTHOR]

The organic-inorganic bioceramic composite microneedles (MNs) were prepared from hydroxyapatite (Hap) and gelatin (Gel) via a template method. The resultant hydroxyapatite and gelatin composite MNs exhibited low cytotoxicity and excellent mechanical properties. After transdermal administration to the diabetic rats, the insulin could be released from bioceramic composite MNs. An obvious and effective hypoglycemic effect could be obtained compared with that of subcutaneous injection route. This work suggests that bioceramic composite MNs containing of insulin have a potential application in diabetes treatment via transdermal ingestion. [ABSTRACT FROM AUTHOR]

Colloidosomes are becoming popular due to their significant flexibility with respect to microcapsule functionality. This study reports a facile approach for synthesizing silica colloidosomes by using sericin microcapsule as the matrix in an environment-friendly method. The silica colloid arrangement on the sericin microcapsules are orchestrated by altering the reaction parameters. Doxorubicin (DOX), used as a hydrophilic anti-cancer drug model, is encapsulated into the colloidosomes in a mild aqueous solution and becomes stimuli-responsive to different external environments, including pH values, protease, and ionic strength are also observed. Colloidosomes with sub-monolayers, close-packed monolayers, and close-packed multi-layered SiO 2 colloid shells can be fabricated under the optimized reaction conditions. A flexible DOX release from colloidosomes can be obtained via modulating the SiO 2 colloid layer arrangement and thickness. The close-packed and multi-layered SiO 2 colloid shells can best protect the colloidosomes and delay the rapid cargo release. MG-63 cells are killed when doxorubicin is released from the microcapsules due to degradation in the microenvironment of cancer cells. The drug release period is prolonged as SiO 2 shell thickness and integrity increase. This work suggests that the hybrid colloidosomes can be effective in a bioactive molecule delivery system. [ABSTRACT FROM AUTHOR]

To reduce the inconvenience and pain of subcutaneous needle injection, the calcium sulfate and gelatin biodegradable composite microneedle patches with high aspect-ratio microneedles (MNs) and a flexible substrate have been developed. The microneedles with an aspect-ratio approximate 6:1 exhibit excellent mechanical property which can achieve 0.4 N for each needle. The cross-section views show the inside of microneedles that have abundant pores and channels which offer potential for different drug-release profiles. The preparation procedures, degradable property for the biodegradable composite microneedle patches are described in the paper. Insulin, the drug to control blood glucose levels in diabetic patients, has been embedded into the biodegradable composite MNs. The hypoglycemic effect for transdermal delivery of insulin is studied using diabetic Sprague-Dawley (SD) rats as models in vivo . After transdermal administration to the diabetic rats, the released insulin from biodegradable composite MNs exhibit an obvious and effective hypoglycemic effect for longer time compared with that of subcutaneous injection route. This work suggests that biodegradable composite MNs containing of insulin have a potential application in diabetes treatment via transdermal ingestion. [ABSTRACT FROM AUTHOR]

A facile and green reversed-phase microemulsion co-precipitation method has been developed for fabrication of CaCO 3 -based composite nanocarriers (NCs) with hyaluronic acid (HA) coatings for oral delivery of insulin. The cell viability of resultant CaCO 3 -based composite NCs against HT-29 cells was analyzed with different concentration. The chemical stability of loaded insulin against digestive enzyme was established in presence of simulated gastric fluid (SGF) containing pepsin. The uptake behavior of HT-29 cells was evaluated by confocal laser scanning microscope (CLSM). After oral administration to the diabetic rats, an effective hypoglycemic effect was obtained compared with subcutaneous injection of insulin. [ABSTRACT FROM AUTHOR]

To overcome multiple barriers for oral delivery of insulin, the chitosan-based multifunctional nanocarriers modified by L-valine (LV, used as a target ligand to facilitate the absorption of the small intestine) and phenylboronic acid (PBA, used as a glucose-responsive unit) have been designed and evaluated in this study. The resultant nanocarriers exhibited low cytotoxicity against HT-29 cells and excellent stability against protein solution. The insulin release behaviors were evaluated triggered by pH and glucose in vitro . The chemical stability of loaded insulin against digestive enzyme were established in presence of simulated gastric fluid (SGF) containing pepsin and simulated intestinal fluid (SIF) containing pancreatin, respectively. The uptake behavior of HT-29 cells was evaluated by confocal laser scanning microscope. After oral administration to the diabetic rats, an effective hypoglycemic effect was obtained compared with subcutaneous injection of insulin. This work suggests that L-valine modified chitosan-based multifunctional nanocarriers may be a promising drug delivery carrier for oral administration of insulin. [ABSTRACT FROM AUTHOR]

With the aim to develop a novel membrane with an appropriate mechanical property and degradation rate for guided bone tissue regeneration, lyophilized and densified silk fibroin membrane was fabricated and its mechanical behavior as well as biodegradation property were investigated. The osteoconductive potency of the silk fibroin membranes were evaluated in a defect rabbit calvarial model. Silk fibroin membrane showed the modulated biodegradable and mechanical properties via ethanol treatment with different concentration. The membrane could prevent soft tissue invasion from normal tissue healing, and the amounts of new bone and defect closure with silk fibroin membrane were similar to those of commercially available collagen membrane. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophobic interactions and hydrogen bonded self-assembly achieve mild functionalization. • The membrane is with anti-fouling, anti-bacteria, and anti-adhesion properties. • The membranes could maintain 85% of adsorption capacity with various interferences. • The membranes could obtain 1.15 mg/g of uranium when the concentration is 3.3 ppb. Herein, we have developed a mild and convenient strategy to enable polypropylene (PP) fibrous membranes with abundant adsorption sites for the selective extraction of uranium from seawater. Lysozyme was chosen as the pre-coatings because of its strong hydrophobic interactions with PP membranes. Then, lysozyme and phytic acid were set as hydrogen bonding self-assembling components since both of them are proved with a great binding affinity towards uranium. The contents and thickness of the lysozyme-phytic acid coatings could be linearly tuned due to the excellent controllability of self-assembly. The obtained PP membrane could achieve adsorption capacity as high as 90.07 mg-U/g-membrane (2143.83 mg-U/g-coating). In addition, the lysozyme would endow the PP membranes with outstanding anti-fouling, anti-bacteria, and anti-adhesion properties. The modified membranes could maintain more than 85% of adsorption capacity even with the interferences of bacteria and model pollutants. We also applied the membranes for dynamic adsorption by taking advantage of membrane filtrations. The adsorption capacity during the dynamic process increases with the flow rates and the layer numbers because more uranyl ions could contact with the adsorption sites. The modified PP membranes could obtain 1.15 mg/g of uranium after 15 days when the concentration of uranium is set as the same as the uranium concentration (3.3 μg/L) in natural seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amyloid-like coatings provide electrodes with binding sites to uranium and anti-fouling properties. • The modified electrodes achieved equilibrium adsorption capacity as high as 2850 mg/g. • Unfolded BSA coatings enable the electrodes with superior reusability and long-term stability. • Both adsorption capacity and adsorption rates are better than most of other adsorbents. Electro-adsorption has been regarded as one of the most effective methods for uranium extraction from seawater since this method could gather ultralow-concentration uranyl ions at the adsorbent surfaces for higher adsorption capacity and adsorption rates. However, the marine microorganisms and pollutants would also migrate to the adsorbent surfaces, causing serious inhibiting effects. Herein, the pristine electrodes were modified by the convenient amyloid-like assembly to solve the above problem. The unfolded bovine serum albumin (BSA) coatings not only offer adsorption sites toward uranium but also enable the electrodes with excellent anti-fouling and anti-adhesion properties. The modified electrodes achieved superior reusability and long-term stability even with the interferences of various pollutants and microorganisms. To the best of our knowledge, the overlooked but pernicious influences of the fouling phenomenon are firstly investigated in electro-adsorption. This finding not only removes the barriers in the practical applications of electro-adsorption, but also guides the design strategy of adsorbents for uranium extraction. [ABSTRACT FROM AUTHOR]

The development of sustainable, biodegradable, non-toxic biomass foams with outstanding physical properties to replace traditional petroleum-based foams is urgent. In this work, we proposed a simple, efficient, and scalable approach to fabricate nanocellulose (NC) interface enhanced all-cellulose foam through ethanol liquid phase exchange and subsequent ambient drying. In this process, NCs served as reinforcer and binder were integrated with pulp fiber to improve cellulose interfibrillar bonding and interface adhesion between NCs and pulp microfibrils. The resultant all-cellulose foam displayed stable microcellular structure (porosity of 91.7–94.5 %), low apparent density (0.08–0.12 g/cm3), and high compression modulus (0.49–2.96 MPa) by regulating the content and size of NCs. Further, the strengthening mechanism of the structure and property of all-cellulose foam were investigated in detail. This proposed process enabled ambient drying, and is simple and feasible for low-cost, practicable, and scalable production of biodegradable, green bio-based foam without special apparatuses and other chemicals. In this work, a simple, efficient and scalable approach was developed to fabricate lightweight, robust and biodegradable all-cellulose foam without special apparatuses and other chemicals. The incorporation of NCs improved cellulose interfibrillar bonding and interface adhesion between NCs and pulp microfibrils, and promoted the formation of stable 3D network structure resisting the increased capillary force in the ambient drainage process. The resultant all-cellulose foam displayed stable microcellular structure, low apparent density, and high compression modulus. [Display omitted] [ABSTRACT FROM AUTHOR]

Development of an oral delivery strategy for insulin therapeutics has drawn much attention in recent years. In this study, a glucose-responsive nanocarriers for loading of insulin has been prepared firstly. The resultant nanocarriers exhibited relative low cytotoxicity against Caco-2 cells and excellent stability against protein solution. The insulin release behaviors were evaluated triggered by pH and glucose in vitro . In order to enhance the oral bioavailability of insulin, the insulin-loaded glucose-responsive nanocarriers were further encapsulated into a three-dimensional (3D) hyaluronic acid (HA) hydrogel environment for overcoming multiple barriers and providing multi-protection for insulin during the transport process. The hypoglycemic effect for oral delivery of insulin was studied in vivo . After oral administration to the diabetic rats, the released insulin from hydrogel systems containing insulin-loaded glucose-responsive nanocarriers exhibited an effective hypoglycemic effect for longer time compared with insulin-loaded nanocarriers. [ABSTRACT FROM AUTHOR]