MOLECULES
·
2023
·Vol. 28
·期 12
·4570
·
IF 4.6
Hongyang Song,Lei Xing,Jinjian Wei,Xue Wang,Yaozhen Yang,Pengbo Zhe,Mingming Luan,Jing Xu
Titanium (Ti) and its alloys are widely used in medical treatment, engineering, and other fields because of their excellent properties including biological activity, an elastic modulus similar to that of human bones, and corrosion resistance. However, there are still many defects in the surface properties of Ti in practical applications. For example, the biocompatibility of Ti with bone tissue can be greatly reduced in implants due to a lack of osseointegration as well as antibacterial properties, which may lead to osseointegration failure. To address these problems and to take advantage of the amphoteric polyelectrolyte properties of gelatin, a thin layer of gelatin was prepared by electrostatic self-assembly technology. Diepoxide quaternary ammonium salt (DEQAS) and maleopimaric acid quaternary ammonium salt (MPA−N+) were then synthesized and grafted onto the thin layer. The cell adhesion and migration experiments demonstrated that the coating has excellent biocompatibility, and those grafted with MPA−N+promoted cell migration. The bacteriostatic experiment showed that the mixed grafting with two ammonium salts had excellent bacteriostatic performance againstEscherichia coliandStaphylococcus aureus, with bacteriostasis rates of 98.1 ± 1.0% and 99.2 ± 0.5%, respectively.Keywords:Ti;osseointegration;antibacterial;electrostatic self-assembly technology
研究领域:
生物材料学
·
医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2012
·
IF 1.867
Guoxin Hu,Bo Tang,Xia Min
By using layer-by-layer self-assembly technology, multilayered films consisting of alternated humic acid and Fe 3 + ions ((HA/Fe 3 + ) n , n = 10,20,40) were fabricated on alumina fiber (AF) substrate for the first time. FTIR and FESEM results show that the (HA/Fe 3 + ) n thin films were effectively immobilized on the AF surface. The average thickness of a single bi-layer HA/Fe 3 + is not sensitive to the total layers. On the contrary, the concentration of Fe 3 + ions significantly influences this mean thickness. A loose and amorphous structure with some irregular pores was detected from the as-prepared specimens, while relatively smooth surface and denser structure were observed after carbonized at 1000 °C. The large BET surface areas and excellent absorbability of the as-prepared and carbonized samples were found. Moreover, at room temperature, a ferromagnetic property of these samples was revealed by magnetism testing. Due to the adjustable number of layers, the ferromagnetic property is controllable. Therefore, these produces possess potential application as the support material in catalytic and target drug delivery areas.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2018
·Vol. 6
·期 1
·016424
·
IF 1.151
Pengfei Li,Hui Liu,Hongyue Chen,Xianhua Cheng
In order to improve the tribological properties of titanium substrate, self-assembly technique was used to prepare a graphene-silane coating: RGO-APTES coating on titanium substrate. The γ-aminopropyltriethoxysilane (APTES) was used to prepare a self-assembled APTES coating as a function of adhesive interlayer, aiming to improve the assembly efficient for graphene coating. The influence of that interlayer on the assembly and tribological properties of graphene coatings on titanium substrate was investigated. Morphology, thickness, chemical characteristic and tribological tests were utilized to investigate the assembly process and tribological properties of coatings. The results show that: (1) the pH values of APTES aqueous solution plays an important role in the molecule orientation of the APTES interlayer, and thus the properties of graphene coating is influenced. When pH is approximately 8.5, the molecule orientation of the interlayer is consistent, so that it has improved adsorption effect on graphene sheets and the graphene coating is uniformly distributed and well-covered; (2) the thickness influences the tribological properties of graphene-APTES coating -- single layered APTES interlayer provides a stronger interlayer strength. The obtained RGO-APTES2 samples have novel friction reducing and wear resisting properties, and can be applied on the surface of titanium substrate as lubricating coating.
研究领域:
材料科学
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表面工程
·
纳米技术
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 4
·2729-2741
·
IF 3.917
Zheng Chenmin,Wen Sili,Teng Ziling,Ye Chunlu,Chen Qiaoling,Zhuang Yuanhong,Zhang Guoguang,Cai Jie,Fei Peng
Abstract In this study, H 2 Ti 2 O 5 ·H 2 O nanotubes (TNTs) prepared through hydrothermal synthesis and TiO 2 used as a raw material were deposited on the surface of bamboo fibre materials through a layer-by-layer (LBL) self-assembly technique to reduce flammability. Scanning electron microscopy indicated that the TNTs were successfully loaded onto the bamboo surface, and their content was dependent on the number of assembled bilayers. Cone calorimetry results showed that the flame retardant performance of the coated bamboo fibre materials improved significantly. As the number of the assembled bilayers increased, performance was further enhanced. When the number of TNTs bilayers was 9, the time to ignition of the bamboo fibre materials was extended from 29.5 s for raw bamboo fibre (RBF) materials to 36.8 s for LBL9. The average heat release rate, total heat release and peak specific extinction area of the fibre materials decreased from 55.67 MJ/m 2 (RBF) to 35.28 MJ/m 2 (LBL9), and their fire performance index increased from 0.123 m 2 s/kW (RBF) to 0.161 m 2 s/kW (LBL9). Differential scanning calorimetry and thermogravimetry results demonstrated that the thermal oxidation and decomposition temperatures of bamboo fibre materials increased from 241.4 °C and 217 °C (RBF) to 311.3 °C and 274 °C (LBL9), respectively. Graphical abstract
研究领域:
材料科学
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纳米技术
·
燃烧学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2020
·
IF 4.469
Yadong Yu,Lei Chen,Ding Weng,Jiadao Wang,Chaolang Chen,Awais Mahmood
Ice accretion is detrimental for the safety of transmission lines, aircraft, and buildings, which may also result in economic loss. In this study, a thin polytetrafluoroethylene (PTFE) coating on the aluminum substrate was fabricated by electrostatic attraction self-assembly technique and proposed for large-scale deicing application. The shear-force F i c e analysis on deicing and related ice adhesion is conducted while interfacial toughness between solid-ice interfaces was also measured. Moreover, the surface morphology, wettability of the PTFE coated aluminum plate was also characterized. It was observed that the critical bonded length L c between ice and PTFE coated surface is about 2.85 cm. When the bonded length L was higher than this value, the shear-force of dislodging ice could stay constant at about 50 N for the first deicing cycle. From the second deicing cycle, the constant shear-force is increased to 70 N and kept constant for at least ten cycles. Meanwhile, the surface roughness and water contact angle kept on increasing along with the loss of PTFE nanoparticles during icing-deicing cycles. Ultimately, An ice layer with the size of 98 cm × 96 cm×1 cm (L × w×h) was developed on the surface of PTFE coated aluminum substrate for the demonstration of its fracture and falling off under ice’s weight.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 10
·4120
·
IF 4.6
Lei Xing,Hongyang Song,Jinjian Wei,Xue Wang,Yaozhen Yang,Pengbo Zhe,Mingming Luan,Jing Xu
Thin oxide layers form easily on the surfaces of titanium (Ti) components, with thicknesses of <100 nm. These layers have excellent corrosion resistance and good biocompatibility. Ti is susceptible to bacterial development on its surface when used as an implant material, which reduces the biocompatibility between the implant and the bone tissue, resulting in reduced osseointegration. In the present study, Ti specimens were surface-negatively ionized using a hot alkali activation method, after which polylysine and polydopamine layers were deposited on them using a layer-by-layer self-assembly method, then a quaternary ammonium salt (QAS) (EPTAC, DEQAS, MPA-N+) was grafted onto the surface of the coating. In all, 17 such composite coatings were prepared. AgainstEscherichia coliandStaphylococcus aureus, the bacteriostatic rates of the coated specimens were 97.6 ± 2.0% and 98.4 ± 1.0%, respectively. Thus, this composite coating has the potential to increase the osseointegration and antibacterial performance of implantable Ti devices.Keywords:Ti;polylysine;self-assembly technology;EPTAC;DEQAS;MPA-N+;cell viability;antibacterial properties
研究领域:
生物材料学
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医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMACROMOLECULES
·
2024
·
IF 5.5
Jie Li,Canhui Lu,Chunhong Ye,Rui Xiong
Iridescent cellulose nanocrystal (CNC) films with chiral nematic nanostructures exhibit great potential in optical devices, sensors, painting, and anticounterfeiting applications. CNCs can assemble into a chiral nematic liquid crystal structure by evaporation-assisted self-assembly (EISA) and vacuum-assisted self-assembly (VASA) techniques. However, there is a lack of comprehensive examinations of their structure–property correlations, which are essential for fabricating materials with unique properties. In this work, we gained insights into the optical, mechanical, and structural differences of CNC films engineered using the two techniques. In contrast to the random self-assembly at the liquid–air interface in EISA, the continuous external pressure in the VASA process forces CNCs to assemble at the filter–liquid interface. This results in fewer defects in the interfaces between tactoids and highly ordered cholesteric phases. Owing to the distinct CNC assembly behaviors, the films prepared by these two methods show great differences in the nanostructure, microstructure, and macroscopic morphology. Consequently, the highly ordered cholesteric structure gives VASA-CNC films a more uniform structural color and enhanced mechanical performance. These fundamental understandings of the relationship of structure–property nanoengineering through various assembly techniques are essential for designing and constructing high-performance chiral iridescent CNC materials.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Qizhi Dong,Tianwu Yin,Hansheng Wan,Guiming Zhu,Gang Yu,Cancheng Guo
Based on electrostatic self-assembly technology, Pd electrocatalyst with high efficiency and excellent CO-tolerance, which is supported on TiO 2 surface modified by amino-rich, cationic poly (diallyldimethylammonium chloride) (PDDA), was prepared. Through electrostatic interaction, Pd precursors were uniformly distributed on TiO 2 (P) and then in situ reduced into Pd nanoparticles (NPs). in such process, PDDA produced a large number of amine to facilitate the uniform distribution of Pd NPs on the surface of TiO 2 . After that，Pd/TiO 2 (P) was mixed with carbon black as anodic catalysts for formic acid oxidation reaction. Transmission electron microscope images and X-ray diffraction patterns revealed that Pd NPs with an average size of ∼3 nm were uniformly dispersed on TiO 2 . Moreover, with the application of cyclovoltammetry and chronoamperometry, we demonstrated the significant enhancement in the electrocatalytic activity and the tolerance toward CO poisoning when compared with Pd/TiO 2 -C for direct formic acid fuel cells.
研究领域:
材料科学
·
电化学
·
能源科学
✓ 已验证
DOI
高影响因子
Membranes
·
2022
·Vol. 12
·期 4
·374
·
IF 4.562
Mingshu Wang,Chang Liu,Min Fan,Meiling Liu,Songtao Shen
Layer-by-layer (LBL) self-assembly technology has become a new research hotspot in the fabrication of nanofiltration membranes in recent years. However, there is a lack of a systematic approach for the assessment of influencing factors during the membrane fabrication process. In this study, the process optimization of LBL deposition was performed by a two-step statistical method. The multiple linear regression was performed on the results of single-factor experiments to determine the major influencing factors on membrane performance, including the concentration of Poly (allylamine hydrochloride) (PAH), glutaraldehyde, and the NaCl concentration in PAH solution. The Box–Behnken response surface method was then used to analyze the interactions between the selected factors, while their correlation with the membrane performance was obtained by polynomial fitting. The R2value of the regression models (0.97 and 0.94) was in good agreement with the adjusted R2value (0.93 and 0.86), indicating that the quadratic response models were adequate enough to predict the membrane performance. The optimal process parameters were finally determined through dual-response surface analysis to achieve both high membrane permeability of 14.3 LMH·MPa−1and MgSO4rejection rate of 90.22%.Keywords:layer-by-layer self-assembly;multiple regression analysis;nanofiltration membrane;process optimization;response surface methodology
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Regenerative Biomaterials
·
2025
·
IF 8.1
Wu Chunwei,Zhong Jie,Li Jianing,Luo Yande,Wang Junyao,Zeng Xiaodie,Mao Jiaji,Lu Jianping,Xu Junyao,Wu Changqiang,Wang Zhiyong
To address the limitations of low relaxivity and physiological toxicity in commercial gadolinium-based contrast agents for magnetic resonance imaging (MRI), a novel manganese chelate macromolecular system was developed using a flash nano-preparation technique. Herein, the approach applying an instantaneous fluid device incorporated gallic acid, dopamine and Mn2+ to perform in-situ polymerization of dopamine and covalent binding with albumin in a nanoconfined environment. This controllable self-assembly process characterized by its scalability and reproducibility was suitable for industrial-scale production. Under optimized flow rates and material ratios, the synthesized ultrasmall protein-based system, Mn-GA@BSA@DA, exhibited excellent aqueous dispersion with an average size of approximately 18 nm, allowing for long-term lyophilized powder storage. More importantly, the nanosystem demonstrated superior MRI-T 1 relaxivity, significantly surpassing that of clinical Gadopentetate dimeglumine, with a high value around 18.5 mM−1 s−1 and a low r 2/r 1 ratio (< 5 at 3.0 T). Furthermore, this Mn-GA@BSA@DA contrast agent was endowed with tumor-targeting effects and long MRI monitoring window period for the liver, gallbladder and renal tubules. The metal chelation within the nanoagent minimizes Mn2+ release; importantly, the antioxidant components, gallic acid and dopamine, significantly inhibit the Fenton reaction-induced toxicity, enhancing biocompatibility. Therefore, this study presents a simple and scalable production technique for a kind of MRI-T 1 weighted contrast agent with high relaxivity and biocompatibility, offering a promising alternative to commercial Gd chelates.
研究领域:
医学影像学
·
材料科学
·
纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
·
IF 6.361
Sheng Shang,Bihe Yuan,Yaru Sun,Gongqing Chen,Chuyuan Huang,Bin Yu,Song He,Huaming Dai,Xianfeng Chen
Melamine-phytate (MEL-PA) nanoflakes are formed by supramolecular self-assembly technology using melamine (MEL) and bio-based phytic acid (PA) as the building blocks. This work explores the possibility of this two-dimensional nanomaterial as flame retardant . The layered MEL-PA with the loading of 1, 2 and 3 wt% are incorporated into polypropylene (PP) matrix. MEL-PA is dispersed well in the PP matrix. Thermal stability and flame retardant performance of PP/MEL-PA composites are investigated. Compared with neat PP, the addition of 2 wt% MEL-PA decreases the peak heat release rate from 756 to 608 kW/m 2 . Char yield of PP is improved by MEL-PA, and the chemical structure and graphitization degree of residual char are studied to reveal flame retardant mechanism.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2020
·
IF 0
Jia Li,Xiang Zhu,Jianyu Wang,Zhiyan Rui,Shiqiao Zhang,Yuxin Li,Rui Ding,Wenxiang He,Jianguo Liu,Zhigang Zou
Nonprecious metal electrocatalysts (NPMEs) have been recognized as highly promising oxygen electroreduction catalysts, but improving their activity and stability in acidic electrolyte remains critical. Here, we integrated self-assembly technology induced by rotary evaporation with the hard-template method to synthesize Fe–N-codoped NPMEs with large specific surface areas and hierarchical pore structure. The presence of Fe3+ assisted complete removal of the ZnO hard template at a relatively low temperature, which is beneficial for both the in situ growth of micropores/mesopores within the carbon layers and the retention of more nitrogen-containing groups. The obtained Fe–N–C/ZnO porous carbon material exhibited outstanding oxygen reduction reaction catalytic activity, along with respectable electrochemical stability in a perchloric acid electrolyte. Applied in fuel cells, the electrocatalyst loading was reduced to 2.0 mg/cm2 because of increased mass transfer arising from the hierarchical porous structure and resulting in a power density of 700 mW/cm2.
研究领域:
材料科学
·
电化学
·
催化化学
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）