Journal of Materials Chemistry A
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2013
·Vol. 2
·期 10
·3445-3451
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IF 0
Jie-Ning Zheng,Jing-Jing Lv,Shan-Shan Li,Meng-Wei Xue,Ai-Jun Wang,Jiu-Ju Feng
In this study, a simple, facile and one-pot solvothermal method was developed for preparation of reduced graphene oxide (RGO) supported hollow Ag@Pt core–shell nanospheres (hAg@Pt), using ethylene glycol (EG) as a reducing agent and sodium dodecyl sulfate (SDS) as a soft template. Control experiments demonstrated that the molar ratios of the Pt–Ag precursors, the amount of SDS, the presence of RGO, and the reaction temperature were critical to the final nanocomposites. The as-prepared hAg@Pt–RGO showed the improved electrocatalytic activity and durability toward ethylene glycol oxidation, which can serve as a promising potential electrocatalyst in direct alcohol fuel cells.
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REACTIVE & FUNCTIONAL POLYMERS
·
2015
·
IF 2.515
Chong Zhang,Lijuan Chen,Lin Tan,Xiajun Zheng,Yanmei Wang
In this study, a set of well-defined multiarm star copolymers , hyperbranched poly(ethylenimine)-graft-poly(ethylene glycol) (bPEI- g -PEG) with different PEG grafting ratios were synthesized. The star PEG-based coatings were then prepared by immobilizing the corresponding copolymers onto poly(dopamine) (PDA)-coated substrates. The chemical composition , hydrophilicity , surface topography , and thickness of the coatings were studied by X-ray photoelectron spectroscopy (XPS), water contact angle (WCA), atomic force microscopy (AFM), and variable angle spectroscopic ellipsometry (VASE), respectively. Furthermore, the surface PEG chain density of star PEG-based coating was evaluated quantitatively and compared with that of linear PEG-based coating. Our results showed that the amount of proteins (albumin from bovine serum, fibrinogen, and lysozyme) adsorbed on the star PEG-based coating as measured by surface plasmon resonance (SPR) was found to be dependent on the surface PEG chain density, which was controlled by the polymer incubation concentrations and PEG grafting ratios. Generally, the star-shaped PEG gave the surface with higher PEG chain density than linear ones and the amount of adsorbed proteins decreased with increasing surface PEG chain density. At last, the star PEG-based coating was successfully applied into the capillary inner surface for protein separation by capillary electrophoresis (CE).
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高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2014
·
IF 0.872
Ruiduan Li,Jianjun Zhang,Jianfeng Chen,Wei Teng,Jiexin Wang,Caixia Li
Hybrid nanoparticles based on lactide and poly(ethylene glycol) were composed of a copolymer , poly(2-amino,1,3-propanediol carbonic ester-co-lactide) [P(LA-co-CA)], and a graft copolymer , poly(2-amino,1,3-propanediol carbonic ester-co- l -lactide)-g-methoxy-poly(ethylene glycol) [P(LA-co-CA)-mPEG]. The hybrid nanoparticles were prepared using emulsion solvent diffusion method. The copolymer of poly(2-benzyloxy amide,1,3-propanediol carbonic ester-co-lactide) was prepared using ring-opening polymerization with diethylzinc (ZnEt 2 ) as a catalyst, and then took off benzyl oxygen group to obtain P(LA-co-CA). P(LA-co-CA)-mPEG by grafting methoxy-PEG-propionaldehyde (mPEG-ALD) on P(LA-co-CA). With docetaxel as a model drug, the morphology of nanoparticles was characterized by scanning electron microscopy (SEM) and the size and size distribution were determined by dynamic light scattering (DLS). The size of DTX-loaded particle was approximately 110 nm. The size scale prevents them from uptake by the reticulo-endothelial system and accumulation at the target site through the enhanced permeability and retention effect. In MTT assay, the results showed that the polymers are non-cytotoxic. The study points to the potential application of the composite nanoparticles in biomedical applications, including tissue engineering and controlled drug delivery.
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Nanoscale
·
2015
·Vol. 7
·期 14
·6104-6113
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IF 7.394
Lei Yang,Weihua Jiang,Lipeng Qiu,Xuewei Jiang,Daiying Zuo,Dongkai Wang,Li Yang
Strong blue fluorescent polyethylene glycol (PEG) anchored carbon nitride dots (CDs@PEG) with a high quantum yield (QY) of 75.8% have been synthesized by a one step hydrothermal treatment. CDs with a diameter of ca. 6 nm are well dispersed in water and present a graphite-like structure. Photoluminescence (PL) studies reveal that CDs display excitation-dependent behavior and are stable under various test conditions. Based on the as-prepared CDs, we designed novel cell nucleus targeting imaging carbon dots functionalized with a nuclear localization signal (NLS) peptide. The favourable biocompatibilities of CDs and NLS modified CDs (NLS-CDs) are confirmed by in vitro cytotoxicity assays. Importantly, intracellular localization experiments in MCF7 and A549 cells demonstrate that NLS-CDs could be internalized in the nucleus and show blue light, which indicates that CDs may serve as cell nucleus imaging probes.
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PubMed
高影响因子
Catalysis Science & Technology
·
2014
·Vol. 4
·期 12
·4308-4312
·
IF 4.76
Ran Ma,Cheng-Bin Huang,An-Hua Liu,Xue-Dong Li,Liang-Nian He
An environmentally benign CO2/glycol reversible acidic system was developed for the iron(III)-catalyzed aerobic oxidative iodination of electron-rich aromatics without the need for any conventional acid additive or organic solvent. Notably, moderate to high isolated yields (up to 97%) of the aryl iodides were attained with comparable regioselectivity when ferric nitrate nonahydrate was used as the catalyst with molecular iodine under 1 MPa of CO2.
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Journal of Materials Chemistry A
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2014
·Vol. 2
·期 32
·12899-12906
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IF 0
Jie-Ning Zheng,Li-Li He,Fang-Yi Chen,Ai-Jun Wang,Meng-Wei Xue,Jiu-Ju Feng
In this work, a facile general strategy is developed for preparation of palladium-based bimetallic alloyed nanodendrites (PdM NDs, M = Pt, Co, and Ni) via coreduction of Pd(II) acetylacetonate and M(II/III) acetylacetonate salts with oleylamine. Hexadecylpyridinium chloride monohydrate (HDPC) is used as a co-surfactant for preventing the aggregation of nanodendrites. Control experiments varying the precursors and reaction time demonstrate that the dendritic nanocrystals are formed via aggregation-based crystal growth. The as-prepared hybrid nanocrystals display improved electrocatalytic activity and better stability for methanol and ethylene glycol (EG) oxidation, compared with home-made Pd NDs and commercial Pd black catalysts. The developed method provides a novel platform for synthesis of novel electrocatalysts in fuel cells.
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CARBOHYDRATE POLYMERS
·
2017
·
IF 4.811
Taotao Xu,Junhua Li,Jun Cao,Wenxia Gao,Li Li,Bin He
Poly(pseudo)rotaxane (PPR) nanoparticles was facilely prepared using poly(ethylene glycol) (PEG) modified with protoporphyrin (PpIX) and α-cyclodextrin (α-CD) via host-guest interaction, the effect of α-CD number on the nanoparticle properties was investigated. The PEG with protoporphyrin (PEG-PpIX) end capping was synthesized via coupling reaction and the poly(pseudo)rotaxane nanoparticles with different amount of α-CD were fabricated by host-guest interaction between mPEG-PpIX and α-CDs. The final product was characterized by nuclear magnetic spectrum ( 1 H NMR), X-ray diffraction (XRD), atomic force microscope (AFM) and dynamic light scattering (DLS). The results showed that the poly(pseudo)rotaxane nanoparticles with uniform spherical shape was successfully prepared and doxorubicin (DOX) could be efficiently encapsulated in the nanoparticles. The amount of α-CDs in poly(pseudo)rotaxane nanoparticles was proportional to micellar size and drug release rate. The nanoparticles with higher α-CD number showed better anticancer efficacy in half maximal inhibitory concentration (IC 50 ) test. The cell internalization efficiency of DOX-loaded poly(pseudo)rotaxane nanoparticles could be further improved by lowering the α-CD number to receive smaller nanoparticle size.
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PubMed
高影响因子
HIGH PERFORMANCE POLYMERS
·
2016
·
IF 1.045
Jiashuang Luan,Chunhua Lu,Yunliang Guo,Feng Li,Guibin Wang
An amphiphilic hyperbranched poly(aryl ether ketone)-graft-poly(ethylene glycol) (HPAEK-graft-PEG) rod–coil copolymer was synthesized by grafting linear PEG onto hydroxyl-terminated HPAEK (OH-HPAEK). The molecular structure, the number-average molecular weight and the thermal properties of HPAEK-graft-PEG were characterized by proton nuclear magnetic resonance and Fourier transform infrared spectroscopies, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis, respectively. The self-assembly behaviors of HPAEK-graft-PEG in the mixed solvents were investigated by transmission electron microscopy and scanning electron microscopy. The results demonstrated that the selective solvent in the used mixed solvents exerted remarkable influence on the morphology of the resulting micelles. When the mixed solvents were water/tetrahydrofuran (THF), trichloromethane/THF, and toluene/THF, that is, with the decrease of the selective solvents in polarity, HPAEK-graft-PEG could self-assemble into the regular microspheres with obvious core–shell structure, the similar quadrilateral-shaped micelles with the dimension of about 20 nm and the large complicated clew-shaped micelles, as well as the irregular large compound micelles, respectively. It is worth mentioning that the similar quadrilateral-shaped micelles were different from the toroidal micelles reported already, which had relatively obvious “angle”. The phenomenon may be ascribed that the rigid characteristic of rod HAPEK segment was conducive to the maintenance of the metastable state.
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高影响因子
Journal of Materials Chemistry B
·
2016
·Vol. 5
·期 5
·961-971
·
IF 4.872
Yan Wen,Fan Li,Chunge Li,Yuji Yin,Junjie Li
High mechanical strength hydrogels without burst release are known to be beneficial to deliver bioactive molecules including drugs and growth factors. Herein, chitosan-based hydrogels are fabricated by the covalent attachment of poly(ethylene glycol) diacrylate (PEGDA) to thiol groups of thiolated natural polymers via Michael addition reaction under physiological conditions. Poly(ethylene glycol-b-caprolactone-b-ethylene glycol) (PECL) micelles bearing double bonds act as both fillers and chemical cross-linkers to mechanically reinforce chitosan-based hydrogels, which is confirmed by the results of rheological behavior and compressive strength measurements. Indomethacin (IMC) and/or basic fibroblast growth factor (bFGF) are/is entrapped into the PECL micelle cross-linked hydrogel network primarily through hydrophobic interaction and specific affinity to thiolated heparin, respectively. After a relatively quick initial release, rather than an initial burst commonly occurring in conventional hydrogels based on drug delivery systems, IMC and/or bFGF are/is released from these PECL micelle cross-linked hydrogels at a slower rate until a steady state is reached. The release rate of IMC and/or bFGF could be readily tuned by varying the micelle amount and the thiolated heparin content in a polymer matrix.
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高影响因子
CATALYSIS COMMUNICATIONS
·
2017
·
IF 3.33
Shengxin Chen,Ruixia Liu,Yajing Li,Ruirui Zhang,Cong Zhao,Hongguo Tang,Congzhen Qiao,Suojiag Zhang
The relationship of basicity and hydrogen bond with catalytic performance was investigated in synthesis of propylene glycol methyl ether (PGME) catalyzed by various ILs ([Emim][OAC], [Bmim][OAC], [N 2222 ][OAC], [EtOHN 111 ][OAC], [N 4444 ]Br, [Bmim][N(CN) 2 ], [Bmim]Br, [Bmim][PF 6 ]). The basicity and Kamlet-Taft parameters of each catalyst were evaluated by UV–visible spectroscopy. It was found the catalytic performance is the synergistic effect of basicity and hydrogen bond donating ability in the synthesis of PGME from PO and CH 3 OH, which is quite different from the conventional basic catalytic mechanism.
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FOOD HYDROCOLLOIDS
·
2024
·
IF 11
Bo Qiu,Huijuan Jing,Shengyi Han,Shuobo Zhang,Furong Ba,Lvwan Xu,Siyuan Xie,Wang Gao,Yilun Huang,Hang Xiao,David Julian McClements,Björn Berglund,Lanjuan Li,Mingfei Yao
Faecalibacterium prausnitzii ( F. prausnitzii ) exhibits a variety of biological functions that make it suitable for use as a next-generation probiotic . However, its high sensitivity to oxygen and digestive fluids currently limits its application. Riboflavin is known to support the growth of F. prausnitzii in oxygen environments, but it is important that it is in close proximity to the probiotics. Layer-by-layer assembly can be used to form protective coatings around probiotics, which can protect them from adverse environmental conditions. Moreover, riboflavin can be conjugated to these coatings, thereby increasing its efficacy by bringing it close to probiotic surfaces. In this study, we therefore evaluated the potential of electrostatic layer-by-layer assembly to protect F. prausnitzii by coating them with riboflavin-alginate and glycol-chitosan layers. Initially, we showed that riboflavin could be successfully conjugated to alginate, with a grafting ratio of around 4.35%. Then, the layer-by-layer method was used to coat F. prausnitzii using cationic glycol chitosan and anionic riboflavin-alginate. The coating formed was found to have a thickness of approximately 18.5 nm. Encapsulation did not adversely affect the growth of F. prausnitzii , but it significantly enhanced its resistance to oxygen and digestive fluids. The encapsulated probiotic was shown to have enhanced mucoadhesive properties using an in vitro intestinal monolayer model. Furthermore, the encapsulated probiotics colonized the colons of rats for longer than nonencapsulated ones. These results show that coating F. prausnitzii with riboflavin-rich biopolymer layers improves its resistance to oxygen and digestive fluids, and enhances its mucoadhesion and colonization properties, which should enhance its potential as an orally administered probiotic.
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Journal of Materials Research and Technology-JMR&T
·
2024
·
IF 6.2
Qian Zhang,Jiawei Li,Qingdi Qu,Shuang Pan,Kunyang Yu,Yushi Liu
The challenge of precisely regulating temperature during the photo-thermal bone promotion remains unresolved. Phase change material (PCM), capable of undergoing a phase transition at a specific temperature, offers a solution by photothermal temperature regulation through the storage and release of heat. This study incorporated biocompatible polyethylene glycol (PEG) with specific phase transition points as PCM. A phase change hydrogel scaffold was then synthesized through semi-crosslinking PEG with calcium-ion-chelated sodium alginate (SA) acting as the structural framework. Additionally, the newly developed graphene oxide (GO) modified composite scaffolds (GO-PHSC), featuring 0.5 wt% GO, not only demonstrated outstanding photothermal conversion efficiency and an optimal phase change temperature (42.2 °C) but also exhibited desirable values for latent enthalpy (100 J/g) and latent heat recovered (LHR) (93.3%). Moreover, the form-stability test demonstrated the PCM scaffolds' exceptional resistance to leakage and maintenance of shape stability even at elevated temperatures (70 °C). Beyond achieving passive temperature control in photothermal therapy, experimental findings highlighted that the phase change hydrogel, incorporating calcium ions and GO, met various requirements such as physicochemical properties, microstructure, mechanics, mineralization, biocompatibility, and cell affinity. These collective attributes suggest that GO-PHSC emerges as a promising scaffold composite candidate for temperature-controlled photothermal therapy in bone regeneration.
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