Polymer Chemistry
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2012
·Vol. 3
·期 9
·2656-2664
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IF 5.321
Chunlei Zhang,Miao Miao,Xueteng Cao,Zesheng An
The arm-first approach is well accepted for the synthesis of core cross-linked star (CCS) polymers, which typically involves two separate steps, i.e., the initial synthesis and purification of the arm polymers followed by a second step synthesis of CCS. We report here a one-pot approach for the RAFT synthesis of a well-defined CCS in water without the separation and purification of the arm polymers. This novel approach consists of a homogeneous polymerization step to prepare the arm polymer, polyPEGMA, and a heterogeneous polymerization step to assemble the arm polymers into CCS polymers. Various parameters affecting the formation of the CCS were studied, including the type of cross-linker, spacing monomer, arm polymer concentration and arm polymer molecular weight. Cross-linkers of longer length provided the flexibility required to form high-quality CCS polymers. The use of spacing monomers in conjugation with cross-linkers reduced the stress during cross-linking and also provided enhanced driving force to produce well-defined CCS polymers. High-quality CCS polymers were prepared at relatively high polymer concentration (≥10%). The higher molecular weight arm polymer exhibited increased steric hindrance for CCS formation. Overall, this one-pot approach is highly efficient, environmentally benign and amenable to a variety of reaction conditions.
研究领域:
高分子化学
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材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·
IF 2.605
Chunning Heng,Meiying Liu,Ke Wang,Fengjie Deng,Hongye Huang,Qing Wan,Junfeng Hui,Xiaoyong Zhang,Yen Wei
Silica nanoparticles (SiO 2 NPs) have been widely applied in a number of domains because of their inodorous, non-pollution, optical transparency, chemical inert and good biocompatibility. However, to achieve better performance, surface modification of SiO 2 NPs to enhance their dispersibility is generally required. In this paper, a simple, facile and environmental friendly procedure was developed for surface modification of SiO 2 NPs with a biocompatible polymer (polyPEGMA) via combination of mussel inspired chemistry and Michael addition reaction for the first time. Firstly, monodisperse SiO 2 NPs were prepared by using a slightly modified Stöber process. Secondly, SiO 2 NPs were coated with polydopamine (PDA), which was formed through self-polymerization of dopamine in an alkaline aqueous solution. Lastly, the PDA coated SiO 2 NPs were facilely conjugated with polyPEGMA, which were synthesized through chain transfer free radical polymerization using cysteamine hydrochloride as chain transfer agent and poly(ethylene glycol) methyl ether methacrylate as the monomer. The successful preparation of these composites was confirmed by a number of characterization techniques including transmission electron microscopy , Fourier transform infrared spectroscopy , thermal gravimetric analysis and X-ray photoelectron spectroscopy. This method obviously enhance the dispersion of SiO 2 NPs in different organic solvents and aqueous solution. This synthetic method is convenient, effective and environmental friendly, that can be also extended to modify SiO 2 NPs with other functional polymers because of the features of mussel inspired chemistry and chain transfer living polymerization .
研究领域:
材料科学
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生物医学工程
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DOI
高影响因子
SURFACE AND INTERFACE ANALYSIS
·
2014
·Vol. 47
·期 2
·270-277
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IF 1.393
Yongli Shi,Suying Ma,Ruiqiong Tian,Yingge Zhao,Qian Jiao,Xu Ma,Qing Shang
A novel amphiphilic copolymer was synthesized from poly (ethylene glycol) methyl ether methacrylate (PEGMA950), methyl methacrylate (MMA) and acryloyl- β -cyclodextrin (acryloyl- β -CD) using the composites of (NH 4 ) 2 S 2 O 8 /NaHSO 3 as the oxidation–reduction initiators. The successful fabrication of poly(PEGMA-co-MMA-co-acryloyl- β -CD) copolymers was confirmed by Fourier transform infrared spectrometer (FTIR), 1 H-nuclear magnetic resonance ( 1 H NMR) spectra. The amphiphilic copolymer could self-assemble into nanoparticles (NPs), and their morphology and particle size distribution were characterized with transmission electron microscopy (TEM), atomic force microscope (AFM) and dynamic light scattering (DLS) methods. Ibuprofen (IBU) was encapsulated in the novel NPs, and the release profiles of IBU were investigated. FTIR and 1 H NMR spectra illustrated that the poly(PEGMA-co-MMA-co-acryloyl- β -CD) copolymers were synthesized without any residual monomers and initiators. TEM and AFM photographs suggested that the obtained NPs were spherical, and the DLS results indicated that the diameter of blank NPs was 157.3 ± 32.7 nm. The IBU release profile showed that the IBU-loaded NPs had certain pH responsibility. Copyright © 2014 John Wiley & Sons, Ltd.
研究领域:
材料科学
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药剂学
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DOI
高影响因子
JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION
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2017
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IF 1.9
Qing Shang,Sijin Huang,Aixin Zhang,Jia Feng,Song Yang
To improve the bioavailability of ibuprofen (IBU), we developed a novel binary complex of poly(PEGMA-co-MAA) hydrogel and IBU-loaded PLGA nanoparticles (IBU-PLGA NPs@hydrogels) as an oral intestinal targeting drug delivery system (OIDDS). The IBU-loaded PLGA NPs and pH-sensitive hydrogels were obtained via the solvent evaporation method and radical polymerization, respectively. The final OIDDS was obtained by immersing the hydrogel chips in the IBU-loaded PLGA NPs solutions (pH 7.4) for 3 d. The size distribution and morphology of cargo-free NPs were studied by laser granularity analyzer and transmission electron microscope (TEM). The inner structures of the pH-sensitive hydrogel chips were observed with an S-4800 scanning electron microscope (SEM). The distribution states of IBU in the OIDDS were also studied with X-ray diffraction (XRD) and differential scanning calorimetry (DSC). TEM photographs illustrated that the PLGA NPs had a round shape with an average diameter about 100 nm. Fourier transform infrared spectrum (FTIR) confirmed the synthesis of poly(PEGMA-co-MAA) hydrogel. The SEM picture showed that the final hydrogel had 3D net-work structures. Moreover, the poly(PEGMA-co-MAA) hydrogel showed an excellent pH-sensitivity. The XRD and DSC curves suggested that IBU distributed in the OIDDS with an amorphous state. The cumulated release profiles indicated that the final OIDDS could release IBU in alkaline environment (e.g. intestinal tract) at a sustained manner. Therefore, the novel OIDDS could improve the oral bioavailability of IBU, and had a potential application in drug delivery.
研究领域:
药剂学
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药物递送系统
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材料科学
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高分子化学
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DOI
PubMed
高影响因子
TALANTA
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2021
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IF 6.057
Yicheng Wang,Dongliang Yang,Yaqin Hu,Yuxin Wang,Wen Jing Yang,Lianhui Wang
Lanthanide nanoprobes have attracted extensive attention for applications in cellular imaging and biological sensing. Herein, water-dispersible europium (III)-based (Eu(III)-based) nanoprobes were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization-induced self-assembly (PISA) of hydrophobic monomers (Eu(III)-containing monomer and methyl methacrylate (MMA)) using hydrophilic macro-chain transfer agent poly(PEGMA)-CTA. The resulted poly(PMEu) nanoprobes showed spherical in shape in good monodispersity with average diameters of around 210 nm. The poly(PMEu) nanoprobles excellent aqueous dispersity, high aqueous stability and good luminescence properties with quantum yields of 37.21% and fluorescence lifetime of 312.4 μs. Moreover, the poly(PMEu) nanoprobes exhibited good cellular biocompatibility with cell viabilities of 88.2% and high fluorescence intensity for in vitro cellular imaging. The present approach provides a facile strategy for fabrication of luminescent Eu(III)-based nanoprobes with great potential applications for biological imaging.
研究领域:
材料科学
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纳米技术
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生物医学工程
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细胞生物学
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DOI
PubMed
高影响因子
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