JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2018
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IF 3.468
Yun Liu,Quan-Quan Wang,Zhi-Ming Jiang,Chuan-Jie Zhang,Zhong-Fang Li,Hua-Qi Chen,Ping Zhu
Chitosan was added to cotton fabrics coated with sodium phytate and 3-Aminopropyl triethoxysilane (APTES) to further enhance the fire retardant property by the layer-by-layer (LBL) assembly. The surface morphologies before and after flaming and structure of coated cotton fabrics were evaluated by scanning electron microscopy and Fourier transform infrared analysis. The thermal degradation properties, fire retardancy, and combustion properties of this system were investigated by Fourier transform infrared analysis, thermogravimetric analysis coupled with Fourier transform infrared analysis (TG-FTIR) in the N 2 atmosphere, the thermogravimetric analysis in air atmosphere, limiting oxygen index test (LOI), vertical burning test and cone calorimeter test, respectively. Sodium phytate, chitosan and hydrolyzed APTES were successfully deposited and well distributed on the surface of cotton fibers. The LOI value of the coated cotton fabric with 15BL was 29.0%, and it extinguished at once in the vertical burning test, while the coated cotton fabrics with 5BL and 10BL were burned out. The deposition of sodium phytate, chitosan and hydrolyzed APTES led to the decrease of heat release rate, total heat release, total smoke release and smoke production rate. The promoted fire retardancy was assigned to thermally stable residuals formed on the surface of cotton fibers, which prohibited heat/mass transfer from combustion zone to polymer degradation zone. TG-FTIR results indicated that flame retardant cotton fabrics produced more nonflammable gases (CO 2 and H 2 O) and less combustible gases than them of the control sample did, increasing flame retardant properties of flame retardant cotton fabrics.
研究领域:
材料科学
·
纺织工程
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
·
IF 8.758
Binbin Zhang,Xin Li,Jianli Zou,Franklin Kim
Diffusion-driven layer-by-layer (dd-LbL) assembly is a simple yet versatile process that can be used to construct graphene oxide (GO) into a three-dimensional (3D) porous framework with good mechanical stability. In particular, the oxygen functional groups on the GO surface are well retained, providing nucleation sites for further chemical reactions to be performed upon. Therefore, such a scaffold should serve as a promising starting material for creating a wide range of 3D graphene-based composites while maintaining a high accessible surface area. Herein, we demonstrate the use of the porous GO macrostructure derived from dd-LbL assembly for the preparation of graphene–MnCO3 hybrid structures. MnCO3 is a newly reported pseudocapacitive material for supercapacitors; however, its electrochemical performance is hampered by its low electrical conductivity and poor chemical stability. Through reaction between KMnO4 and GO during a hydrothermal process, the surface of the porous scaffold was rendered with uniform MnCO3 nanoparticles. With the reduced graphene oxide (rGO) sheets serving as the conductive backbone, the resultant MnCO3 nanoparticles exhibited a capacitance of 698 F g–1 at a charge/discharge current of 0.5 mA (320 F g–1 for the combined rGO and MnCO3 composite). Furthermore, the electrode maintained 77% of its initial capacity even after 5000 cycles of charge/discharge tests at 20 mA.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ACS Nano
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2022
·
IF 18.027
Jianfeng Li,Shuang Yi,Kaiqiang Wang,Yanfei Liu,Jinjin Li
Black phosphorus (BP) is a promising material for electronic and optoelectronic applications. However, it is still challenging to obtain geometrically well-defined BP with desirable thickness. The method involving rapid BP surface reaction via alkene-catalyzed oxidation and easy removal of reactants by a mechanical effect was proposed to achieve the precise layer-by-layer thinning and real-time thickness monitoring of BP for nanopatterning with high spatial resolution based on mechanical scanning probe nanolithography. The enhanced electron affinity of oxygen with the assistance of a carbon–carbon double bond (C═C) in the alkene was demonstrated by density functional theory calculations, shortening the BP surface oxidation period by 99%, which provides access for the rapid thinning. The few-layer BP nanoflake with nested structure and arbitrary thickness on various substrates and the nanopatterned heterojunctions (BP/graphene and BP/hexagonal boron nitride) can be precisely fabricated by the adjustment of scanning number under a small load. This thinning technology was efficient and universal, which could be used to fabricate a BP field-effect transistor with a thinned channel to enhance the capability for current modulation, showing great potential applications for designing high-performance nanodevices.
研究领域:
材料科学
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纳米技术
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电子工程
✓ 已验证
DOI
高影响因子
MACROMOLECULAR BIOSCIENCE
·
2024
·Vol. 24
·期 8
·2400015
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IF 4.4
Zhiwen Zheng,Xueyang Li,Xin Dai,Chang Du
Vascular transplantation is a common treatment for Cardiovascular disease (CVD). However, the mismatch of mechanical, structural, or microenvironmental properties of materials limits the clinical application. Therefore, the functional construction of artificial vessels or other blood contact materials remains an urgent challenge. In this paper, the composite nanofibers of polycaprolactone (PCL) with dopamine and polyethylenimine (PEI) coating are first prepared, which are further self-assembled by anticoagulant hirudin (rH) and antimicrobial peptide (AMP) of HHC36 through layer-by-layer (LBL) method. The results of FTIR and XPS analysis show that hirudin and AMP are successfully loaded on PEI-PDA/PCL nanofibers and the hydrophilicity is improved. They also show good mechanical properties that the ultimate tensile strength and elongation at break are better than natural blood vessels. The antibacterial results show that the antibacterial effect is still 93% against E. coli on the fifth day because of the stable and continuous release of HHC36 and rH. The performance of anticoagulant activity also exhibited the same results, which APTT is even 9.7s longer in the experimental group than the control group on the fifth day. The novel materials would be effectively solve the formation of thrombosis around artificial blood vessel grafts and the treatment of inflammation.
研究领域:
生物医学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
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2023
·Vol. 15
·期 5
·1077
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IF 5
Shuo Li,Li Shi,Ting Ye,Biao Huang,Yuan Qin,Yongkang Xie,Xiaoyuan Ren,Xueqin Zhao
Antibiotic abuse in the conventional treatment of microbial infections, such as inflammatory bowel disease, induces cumulative toxicity and antimicrobial resistance which requires the development of new antibiotics or novel strategies for infection control. Crosslinker-free polysaccharide-lysozyme microspheres were constructed via an electrostatic layer-by-layer self-assembly technique by adjusting the assembly behaviors of carboxymethyl starch (CMS) on lysozyme and subsequently outer cationic chitosan (CS) deposition. The relative enzymatic activity and in vitro release profile of lysozyme under simulated gastric and intestinal fluids were investigated. The highest loading efficiency of the optimized CS/CMS-lysozyme micro-gels reached 84.9% by tailoring CMS/CS content. The mild particle preparation procedure retained relative activity of 107.4% compared with free lysozyme, and successfully enhanced the antibacterial activity againstE. colidue to the superposition effect of CS and lysozyme. Additionally, the particle system showed no toxicity to human cells. In vitro digestibility testified that almost 70% was recorded in the simulated intestinal fluid within 6 h. Results demonstrated that the cross-linker-free CS/CMS-lysozyme microspheres could be a promising antibacterial additive for enteric infection treatment due to its highest effective dose (573.08 μg/mL) and fast release at the intestinal tract.Keywords:lysozyme;carboxymethyl starch;chitosan;layer-by-layer self assembly;enteric infection
研究领域:
药学
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生物技术
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2014
·Vol. 3
·期 7
·1391-1404
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IF 0
Lingren Wang,Baihai Su,Chong Cheng,Lang Ma,Shuangsi Li,Shengqiang Nie,Changsheng Zhao
In this study, to approach the scalable fabrication of super-hemocompatible and antibacterial membranes, surface engineered 3D heparin-mimicking coatings were designed by layer by layer (LBL) assembly of water-soluble heparin-mimicking polymer (WHP) and quaternized chitosan (QC). The low cost and scalable WHP was synthesized by a combination of polycondensation and post-carboxylation method, and the antibacterial QC was prepared by a two-step quaternization reaction. Then, the as-prepared negatively charged WHP and positively charged QC were used to conduct the LBL assembly on the widely used poly(ether sulfone) (PES) membrane surface to prepare heparin-mimicking modified membrane. The results indicated that the assembled heparin-mimicking coating nanofilms exhibited 3D porous morphology. The systematic blood compatibility and antithrombotic evaluation revealed that the functionalized membrane owned prolonged clotting times and greatly suppressed platelet adhesion and activation; further contacting activation detection (TAT and PF-4) and complement activation (C3a and C5a) experiments indicated that the heparin-mimicking membranes had lower blood activation compared to the pristine membrane. The cell observations demonstrated that the surface assembled heparin-mimicking nanofilms showed superior performances in endothelial cells adhesion and growth than the pure PES membrane. The results of the antibacterial study indicated that the QC contained coating exhibited significant inhibition ability for both Escherichia coli and Staphlococcus aureus. In general, the LBL assembled heparin-mimicking coatings conferred the functionalized PES membranes with integrated blood compatibility, cytocompatibility and antibacterial property for multi-applications, which may forward the fabrication and application of heparin-mimicking biomedical devices.
研究领域:
生物材料
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医学工程
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表面化学
✓ 已验证
DOI
PubMed
Polymers
·
2019
·Vol. 11
·期 11
·1782
·
IF 3.164
Lin Gu,Meng-Yun Xie,Yu Jin,Min He,Xiao-Yan Xing,Yuan Yu,Qing-Yun Wu
Lignin is the second most abundant and low-cost natural polymer, but its high value-added utilization is still lack of effective and economic ways. In this paper, waste lignosulfonate (LS) was introduced to fabricate antifouling membrane surfaces via layer-by-layer self-assembly with polyethyleneimine (PEI). The LS/PEI multilayers were successfully deposited on the polysulfone (PSf) membrane, as demonstrated by ATR-FTIR, XPS, Zeta potential measurements, AFM, and SEM. Meanwhile, the effect of the number of bilayers was investigated in detail on the composition, morphologies, hydrophilicity, and antifouling performance of the membrane surface. As a result, with the bilayer numbers increase to 5, the PSf membrane shows smooth surface with small roughness, and its water contact angle reduces to 44.1°, indicating the improved hydrophilicity. Accordingly, the modified PSf membrane with 5 LS/PEI bilayers repels the adsorption of protein, resulting in good antifouling performance. This work provides a green, facile, and low-cost strategy to construct antifouling membrane surfaces.Keywords:lignin;polysulfone membrane;layer-by-layer self-assembly;antifouling;surface modification;hydrophilic
研究领域:
材料科学
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环境工程
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化学工程
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产品关联
DOI
PubMed
高影响因子
Polymers
·
2021
·Vol. 13
·期 19
·3270
·
IF 4.329
Sihan Zhang,Zhihua Xu,Jiaqi Guo,Haiying Wang,Yibo Ma,Xianming Kong,Hongtao Fan,Qian Yu
Polystyrene (PS) spheres were prepared through an emulsifier-free emulsion polymerization method, in which the reaction time, ionic strength, concentrations of copolymer were studied in detail. The resulting PS microspheres and Ag nanoparticles were used to construct a surface enhanced Raman scattering (SERS) substrate by a layer-by-layer assembly method. A relatively uniform distribution of PS/Ag in the films was obtained, and the multilayer substrate presented excellent SERS reproducibility and a tunable enhancement effect. The SERS substrate was used for detecting harmful pesticides (malachite green and dimetridazole) in food samples, with a limit of detection as low as 3.5 ppb. The obtained plasmonic composite has a promising future in the field of SERS sensing.Keywords:polystyrene;self-assembly;Ag nanoparticle;layer by layer;SERS;reproducibility
研究领域:
材料科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
Biomedical Materials
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2022
·Vol. 17
·期 3
·035006
·
IF 4.103
Haibo Wang,Ao Dong,Kun Hu,Weiwei Sun,Jundong Wang,Lu Han,Lixin Mo,Luhai Li,Wei Zhang,Yan Guo,Li Zhu,Fuzhai Cui,Yen Wei
Poly L-lactic acid (PLLA) is a non-toxic, biocompatible degradable polymer material with excellent mechanical properties after moulding. However, it faces challenges in the use of biomedical materials because of its intolerance to bacteria. Here, we use an easy-to-operate method to prepare a composite multilayer membrane: PLLA membrane was used as substrates to assemble positively charged chitosan and negatively charged Ag@MXene on the surface using the layer-by-layer (LBL) method. The assembly process was detected by fluorescein isothiocyanate-labelled chitosan and the thickness of the coating multilayer was also detected as 210.0 ± 12.1 nm for P-M membrane and 460.5 ± 26.5 nm for P-Ag@M membrane. The surface self-assembled multilayers exhibited 91.27% and 96.11% growth inhibition ratio against Escherichia coli and Staphylococcus aureus strains under 808 nm near-infrared laser radiation with a synergistic photothermal antibacterial effect. Furthermore, best biocompatibility of P-M and P-Ag@M membranes compare to PLLA membrane motivated us to further explore its application in biomedical materials.
研究领域:
材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Yangxiao Yu,Mengnan Dai,Meng Li,Guangzhou Song,Yin Yin,Jiannan Wang
For severe local vasculopathy, covered stents are considered the major medical devices in interventional therapy due to their function to isolate lesions and deliver drugs. However, commercial stent-coverings have unsatisfactory drug-loading capacity and lack bioactivity. Silk fibroin (SF) possesses excellent biocompatibility, biodegradability, and endothelialization ability. In this study, we developed a bioabsorbable SF stent-covering loaded with heparin (Hep) via layer-by-layer self-assembly. Hep was embedded in the stent-covering via interfacial adsorption (Hep-SF) or direct blending with SF (Hep/SF). For interfacial adsorption, the Hep loading capacity increased with adsorption time and Hep concentration, reaching up to 589 μg/cm2. All Hep-modified SF stent-coverings were nonhemolytic. After Hep modification, the recalculation time of the Hep-SF stent-covering was significantly prolonged (>2 h), platelet adhesion to its surface was reduced, and no obvious clots formed. Compared to the Hep/SF stent-coverings, the release quantity of Hep from the Hep-SF stent-covering was higher at each time point, regardless of diffusion or enzymatic degradation, but its diffusion release rate was lower than that of the high-dosage Hep/SF stent-covering, suggesting that the Hep-SF stent-covering had more sustained Hep release. Moreover, the released Hep maintained a high anticoagulant activity to significantly prolong activated partial thromboplastin time and thrombin time after long-time diffusion or enzymatic degradation. The results indicated that the Hep-SF stent-covering developed in this study not only had a high loading capacity for anticoagulant drugs (on-demand adjustable) but also could achieve effective and sustained anticoagulant function until the SF material was completely degraded.
研究领域:
生物材料学
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药物递送系统
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血管介入治疗
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CORROSION SCIENCE
·
2020
·
IF 6.479
Daquan Zhang,Jiamin Lu,Cheng Shi,Kai Zhang,Jin Li,Lixin Gao
Constructing the films with remarkable anti-corrosion performance is the key issue to metal protection. A kind of covalent layer-by-layer (LbL) assembly films of triazole is fabricated on the copper surface in this work. The covalent LbL system provides a promising and efficient protection. The optimum assembly layers are three and the best protection efficiency is 96.9 %. Enhancement in corrosion resistance is due to the formation of the covalent triazole films via the click chemistry reaction catalysed by cuprous oxide. The mechanism of protection is discussed via the surface analysis and the molecular dynamics simulation.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Xiaoyan Li,Fuxun Qi,Jixiang Zhu,Xinsheng Niu,Shengbing Yang,Deng-Guang Yu
Constructing bio-based antibacterial composite multilayer coatings with sustained drug release is important for reducing the infection risk of bone tissue repair. In this paper, a layer-by-layer aqueous electrodeposition method was applied to prepare a bio-based composite coating of chitosan, hyaluronic acid, and chitosan quaternary ammonium salt on the titanium surface. By pretreating with poly (acrylic acid), controlling the electrochemical deposition process, and post-treating with glutaraldehyde, a multi-layer composite coating with a smooth surface, good interface bonding with the titanium substrate, and a thickness more than ten microns was obtained. The composite coating was used as a drug-carrying system for gentamicin sulfate, which showed obvious antibacterial effects against Escherichia coli and Staphylococcus aureus . The bio-based composite coating with a sandwich structure loaded with antibiotics effectively inhibited the burst release of antibiotics, and the 14-day release rate is only 68.4 ± 2.1 %, achieving sustained release of the drug. The hydrophilic chitosan quaternary ammonium salt on the surface of the composite coating can effectively inhibit the early adhesion of bacteria, while the slow release of gentamicin sulfate in the interlayer can exert a long-lasting antibacterial effect. The preparation of bio-based antibacterial composite coatings using a layer-by-layer electrodeposition strategy has promising applications in titanium orthopedic implants.
研究领域:
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）