POLYMER
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2011
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IF 3.829
Qianling Cui,Feipeng Wu,Erjian Wang
A novel oxazolidine based acid-labile monomer N -acryloyl-2,2-dimethyl-1,3-oxazolidine (ADMO) was synthesized and polymerized by reversible addition fragmentation chain transfer (RAFT) polymerization using poly(ethylene glycol) based chain transfer agent (PEG-CTA). The diblock copolymers PEG- b -PADMO were composed of hydrophilic PEG with fixed length and hydrophobic PADMO with different lengths, which formed core-shell micelles in water. Morphologies and sizes of micelles were obtained by transmission electron microscopy (TEM) and dynamic light scattering (DLS), which showed that the shapes of polymeric aggregates developed from small spherical micelles, worm-like micelles to larger size of vesicles, as the length of PADMO increased. The hydrolysis kinetics of the micelles was studied using 1 H NMR, DLS and release of loaded Nile Red dye, whose rate strongly depended on pH and micellar structure . It led to the disruption of polymeric micelles and concomitant release of the guest molecules, due to the transformation of hydrophobic PADMO into hydrophilic poly(2-hydroxyethyl acrylamide) (PHEAM).
研究领域:
聚合物化学
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材料科学
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纳米技术
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胶体科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Nano
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2022
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IF 13.364
J. Wu,P. Wu,X. Weng,J. Lin,G. Owens,Z. Chen
Recently, the green synthesis of iron nanoparticles and associated hybrids using plant extracts has attracted much attention due to its low cost, simplicity and environmental friendliness . However, the exact formation mechanism is still unclear. In this study, the one step green synthesis of hybrid rGO/Fe NPs by a tea extract was examined using a response surface methodology (RSM) to obtain a high activity of rGO/Fe NPs. The results showed that the best conditions for synthesis were an extract concentration = 35 g/L, pH = 7, and temperature = 30 °C. The optimized hybrid produced could remove 99.9% of mitoxantrone (MTX) compared to only 78.9% when unoptimized. To better understand the formation process, characterizations by SEM , TEM, AFM , FTIR, XRD , Raman, and XPS were performed. Theses characterizations showed that the Fe NPs produced had a particle size of 25 nm which were deposited randomly across the rGO nanosheet with a thickness of approximately 1.5 nm, indicating that stable hybrid rGO/Fe NPs were successfully synthesized, where the green tea extract exhibited both reducing and capping/stabilizing behavior. Furthermore, the specific biomolecules in the green tea extract responsible for bio-reduction and stabilization were identified by GC-MS and LC-MS, which showed that catechins were the main reducing agents, while alkaloids, amino acids and phenolic acids were the main capping/stabilizing agents. Finally, a mechanism for synthesizing rGO/Fe NPs was proposed, where the polyphenols successfully reduced GO and complexed with iron ions to form amorphous ferric (and ferrous) polyphenol complex nanoparticles.
研究领域:
材料科学
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纳米技术
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环境科学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
Acta Biomaterialia
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2019
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IF 6.638
Jingdong Rao,Ling Mei,Ji Liu,Xian Tang,Sheng Yin,Chunyu Xia,Jiaojie Wei,Dandan Wan,Xuhui Wang,Yashi Wang,Man Li,Zhirong Zhang,Qin He
Autophagy plays a key role in the stress response of tumor cells, which contributes to cancer cell survival and resistance to chemotherapy by degrading cytoplasmic proteins to provide energy and clear the hazardous substances. Therefore, combined treatment of chemotherapeutics and autophagy inhibitors is thought to obtain a desirable antitumor effect. Nanoparticles (NPs) show potential in tumor-targeting drug delivery because of the enhanced permeability and retention (EPR) effect. However, NPs with fixed particle size cannot achieve optimal delivery effect. Herein, a strategy based on Cu (I)-catalyzed click chemistry-triggered aggregation of azide/alkyne-modified micelles was developed for the co-delivery of the chemotherapeutic drug doxorubicin (Dox) and the autophagy inhibitor wortmannin (Wtmn). In vitro experiments showed that the size of micelles increased in a time-dependent manner, which enhanced micelle accumulation in both B16F10 and 4 T1 cells. The fluorescence resonance energy transfer (FRET) experiment and biodistribution study further demonstrated that the aggregation of micelles through click cycloaddition significantly improved the accumulation of drug-loading micelles at the tumor region. Furthermore, the decreased amount of autophagosomes observed by transmission electron microscopy (TEM), the declined expression of LC3-II, and the increased level of p62 by western blotting and immunohistochemistry (IHC) confirmed the obvious inhibition of autophagy induced by Dox/Wtmn co-loaded size-adjustable micelles, which had a synergistic effect in cancer suppression. In addition, the co-loaded size-adjustable micelles showed outstanding cytotoxicity and antitumor effect. Therefore, this strategy effectively suppressed melanoma and breast cancer in mice. Statement of Significance The therapeutic effects of chemotherapy can be limited by autophagy; hence, combined use of autophagy inhibitors with chemotherapeutics achieves desirable anticancer efficacy. In the present study, we designed size-adjustable micelles by modifying the click reaction substrate azide group and the alkyne group on the surface of micelles, and subsequently, the autophagy inhibitor wortmannin and the chemotherapeutic drug doxorubicin were co-loaded. The micelles could aggregate by click reaction at the tumor site when the catalysts were intratumorally injected. The results showed that the size-adjustable micelles achieved efficient drug delivery, penetration, and retention in tumors; through the combined effect of wortmannin-mediated autophagy inhibition and doxorubicin-mediated cytotoxicity, this strategy exerted significant anticancer effect in melanoma and breast cancer treatment.
研究领域:
药学
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纳米技术
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肿瘤学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CATALYSIS LETTERS
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2023
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IF 2.8
Hao Runming,Du An,Zhu Qingling,Wu Xue,Liu Sijia,Wang Ke,Wang Yang
5-Hydroxymethylfurfural (HMF) is a high value-added platform compound, converted into bio-based polyesters and biofuels etc. In this paper, we used two commercially available hexamethylenimine and cetyltrimethylammonium bromide (CTAB) as the structure-directing agents to synthesize HMWW zeolite nanosheets via one step. A series of HMWW zeolite nanosheets with different disorder index ( DI ) were controllably prepared by adjusting the amount of CTAB, operating also as an in situ exfoliating agent, converting fructose into HMF in the tetrahydrofuran/NaCl-H 2 O biphasic solvent with low boiling point. Successful construction of disordered HMWW zeolite nanosheets was verified by PXRD. Further characterizations by BET, SEM and TEM etc. show that HMWW 4.0 with the optimum DI of 0.67 has a disordered network-like arrangement of layers with the external surface area of 224 m 2 /g and the mesoporous size of 3.5 nm. Catalytic evaluations showed that HMF selectivity was closely related to DI of the catalysts. Under the optimized DI , fructose molecules are readily accessible to acidic sites on the external surface while larger external surface area is exposed. The HMWW 4.0 zeolite catalyzed fructose dehydration in the biphasic solvent, producing 90% HMF selectivity with 93% fructose conversion at 140 °C for 6 h. In the reuses of the HMWW 4.0 catalyst, HMF selectivity was around 90% with fructose conversion decreasing by ca. 10% after six runs, indicating that it possesses the promising stability. Graphical Abstract
研究领域:
化学
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材料科学
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催化
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纳米技术
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2022
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IF 10.319
Yue Liu,Feng Peng,Guang-Ling Yang,Zhi-Hui Xie,Wenxin Dai,Yuejun Ouyang,Liang Wu,Chuan-Jian Zhong
The utilization of photoelectrochemical cathodic protection (PECCP) enables an indirect corrosion protection of metals with low self-corrosion potential by introducing a metallic nickel interlayer. However, the ability to enhance the PECCP efficiency remains challenging because of the inherent property of the semiconductor. Herein, this ability is demonstrated by coupling a covalent organic framework (TpBD) decorated TiO 2 photoanode (TiO 2 /TpBD) with nickel coating on magnesium alloy for an effective corrosion protection. The composite photoanode showed direct PECCP for the nickel interlayer and indirect corrosion protection of the magnesium alloy. The composite structure of the nanotube array and the covalent organic framework for the photoanode were confirmed by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The enhanced photoelectrochemical conversion capability and PECCP performance of the nickel-coated Mg alloy were evidenced by the results from electrochemical and photoelectrochemical measurements including Mott-Schottky curves, photoinduced potential variations, and electrochemical impedance spectroscopy (EIS). Lastly, a corrosion protection mechanism is proposed, where the enhanced PECCP efficiency is attributed to the formation of a direct Z-scheme heterojunction, which is substantiated by the results from valence band (VB) XPS and electron spin resonance characterizations.
研究领域:
材料科学
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电化学
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腐蚀科学
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光电化学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
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2022
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IF 3.754
Jingtao Zhang,Mengwan Zhai,Xueying Wang,Shurui Liu,Lijuan Zhang,Xing Liu,Yao Geng,Xiaodong Sun,Bingkun Liu
In the present work, Ti 3+ -self-doped TiO 2 heterostructure photocatalysts were prepared by coupling with different additions of palladium quantum dots by means of deposition-reduction methodology. The electron paramagnetic resonance (EPR) analysis indicated the existence of Ti 3+ in synthesized samples. The transmission electron microscopy (TEM) images presented the modification of TiO 2-x nanoparticles by coupling with nano palladium. Photoluminescence (PL) results demonstrated the lowest charge carrier recombination rate in 5% Pd/TiO 2-x composites. Photocatalytic performances of photocatalysts were evaluated by degrading Tetracycline (TC) and inactivating Escherichia coli ( E. coli ) and Fusarium oxysporum f. sp. Vasinfectum ( Fov ) with the presence of visible light , in which an enhanced photocatalytic degradation and inactivation activity was found in all Pd coupled composites with the highest efficiency in 5% Pd/TiO 2-x . The improved photocatalytic activity of Pd/TiO 2-x was associated to the generation of more hydroxyl radicals (•OH) and superoxide anions radicals (•O 2- ) during photocatalytic process which were demonstrated by the electron spin-resonance spectroscopy (ESR) technique. Moreover, 5% Pd/TiO 2-x composites were found to remain high photocatalytic properties in a circulating photo-disinfection system.
研究领域:
材料科学
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环境科学
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纳米技术
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光催化
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水处理
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2022
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IF 10.723
Lianxiong Guan,Zhi Zeng,Wei Liu,Tengfei Wang,Shiyao Tian,Sheng Hu,Dating Tian
Amphiphilic AIE nanoparticles (CD-TPE) were obtained by linking γ-cyclodextrin (γ-CD) and 1, 2-diphenyl-1, 2-( p -hydroxyphenyl)-ethylene (OH-TPE-OH) by an esterification reaction using hexamethylene diisocyanate (HMDI) in a one-step process. The CD-TPE was characterized by FTIR, 13 C NMR, DSC , XRD, particle size analysis , TEM, and FL. The obtained CD-TPE had good water dispersibility and could self-assemble into AIE nanoparticles. The large cavity of CD-TPE provided convenient conditions for the loading of doxorubicin (DOX) and slow-release DOX with the loading and release rates of 67.4 % and 71.3 % (pH = 5.4), respectively. The DOX release kinetic model was suitable for the Bhaskar model. Cytotoxicity analysis and cell imaging of CD-TPE were performed, showing that CD-TPE has good biocompatibility and excellent cell imaging performance. Moreover, both in vitro and in vivo antitumor experiments showed that CD-TPE has promising applications in drug delivery.
研究领域:
生物医学工程
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纳米技术
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药学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DIAMOND AND RELATED MATERIALS
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2023
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IF 4.1
Qihui Chen,Hao Zhang,Haibo Liu,Jianyang Yuan,Yong Gao,Chaoyang Wu,Qi Wang,Guizhe Zhao,Yaqing Liu
The surface topography and interface characteristics play a significant role in determining the mechanical properties of carbon fiber reinforced polymer (CFRP) composites. These features are primarily influenced by the surface chemical structures and their interactions with the matrix resin . Here, we developed a rigid-flexible coating consisting of polyetheramine (PEA) and polydopamine (PDA) on the fiber surface to control the interface and improve the mechanical properties of CFRPs . X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectrum (FT-IR) results validated the successful introduction of polymeric chains and fiber surface characteristics including rough surfaces, slim polymer layers and uniform dots were examined by scanning electron microscope (SEM) and transmission electron microscopy (TEM). Contact angle tests indicate that the functionalized coating noticeably enhances the interaction force between carbon fibers, promoting improved wettability by the matrix resin. The bending and interlaminar shear strength of CFRP prepared by functional carbon fiber are increased by 45.76 % and 47.63 %, respectively. The drop weight impact (DWI) test confirms the positive effect of improved interfacial properties on the out-of-plane impact resistance of CFRPs.
研究领域:
材料科学
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复合材料
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高分子科学
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Zhixin Jia,Jingbin Zhang,Zengtao Ji,Xinting Yang,Ce Shi,Xia Sun,Yemin Guo
To address the growing challenge of counterfeit prevention, this study developed a novel anti-counterfeiting ink system based on bacterial cellulose nanocrystals (BCNC) and lanthanide (Er, Yb)‑nitrogen (N) co-dropped graphene quantum dots (GQDs), which exhibited both photoluminescence (PL) and upconversion photoluminescence (UCPL) fluorescent properties as well as excellent rheological characteristics . The Er/Yb/N-GQDs with positive charges were synthesized by a one-step hydrothermal method and subsequently assembled with negatively charged BCNC through electrostatic self-assembly to fabricate a novel nanohybrid , Er/Yb/N-GQDs-BCNC. Raman spectroscopy results indicated an enhancement in the graphitization of GQDs due to lanthanide modification. The TEM results demonstrated a homogeneous distribution of Er/Yb/N-GQDs on BCNC, while XRD , FTIR, and XPS analyses confirmed their physical binding, thus validating the successful synthesis of novel nanohybrids. Then, Er/Yb/N-GQDs-BCNC was introduced into PVA waterborne ink and exhibited dual anti-counterfeiting properties by emitting blue fluorescence at Em 440 nm under Ex 370 nm and green fluorescence at Em 550 nm under Ex 980 nm. Furthermore, the incorporation of BCNC significantly enhanced the thixotropic behavior and yield stress of the PVA waterborne ink. This enhancement made the dual anti-counterfeiting fluorescent ink more suitable for diversified applications on different devices and various substrates, thus providing a novel approach for convenient and rapid information encryption and high security anti-counterfeiting.
研究领域:
材料科学
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化学
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纳米技术
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光学
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防伪技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）