INTERNATIONAL JOURNAL OF PHARMACEUTICS
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2015
·
IF 3.65
Li Qingcong,Pan Xiaoxia,Li Hongli,Yuan Minglong
A relatively high molecular weight of 4-arm star PELA was obtained by ring-opening polymerization of l -lactic acid O -carboxyanhydride with 4-arm-PEG in the presence of DMAP as an initiator. The results via 1 H NMR and 13 C NMR show that the end of the star PELA chain is a hydroxyl group and the central core is a PEG group. Rotavirus (strain SA11) was incorporated into 4-arm star PELA microspheres formulated by the water in oil in water emulsification solvent extraction method. The microspheres produced were spherical, and the mean diameter was 1.34 μm with a narrow size distribution. The drug release profile displayed a low burst release effect of 1.8% on the first day and a sustained release of antigen over 100 days. After the immunization of mice, the microsphere-entrapped RV elicited improved and long-lasting IgA and IgG antibody response in serum detected by ELISA in comparison to the free RV antigen. This study shows that 4-arm-PEG is an effective initiator for the ring-opening polymerization of Lac-OCA by DMAP as an initiator and that the resulting polymer is useful as a delivery system for the rotavirus vaccine .
研究领域:
生物材料学
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疫苗学
·
药剂学
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DOI
PubMed
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2015
·Vol. 216
·期 14
·1507-1515
·
IF 2.616
Yunna Kong,Wenyu Li,Qianying Mao,Youxiang Wang
Supramolecular assembly provides a new strategy for designing various gene carriers for deoxyribonucleic acid (DNA) delivery. In this work, supramolecular pseudo-block conjugates based on star-shaped polycation are developed as novel nonviral gene vector. First, cyclodextrin (CD) is selected as core and grafted with low molecular weight polyethylenimine (PEI 1800 ) as arms to obtain high molecular weight star-shaped polycation CD-PEI 8 (SCP). Then, azobenzene (Az) modified poly(ethylene glycol) is synthesized and named as azobenzene modified poly(ethylene glycol) (Az-PEG). Subsequently, the supramolecular pseudo-block conjugates are prepared via host–guest interaction between CD and Az. The result suggests that SCP/Az-PEG condenses DNA into spherical nanoparticles with sizes of around 150 nm. The in vitro experiment shows that the cell viability of DNA/SCP/Az-PEG polyplexes is significantly improved compared with that of PEI 25k /DNA polyplexes. The PEGylation does not decrease the cellular uptake efficiency and transfection efficiency. Furthermore, the cellular trafficking shows that PEGylation does not significantly influence nuclear entry. The star-shaped architecture of polycation plays an important role in gene delivery.
研究领域:
生物医学工程
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分子生物学
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药剂学
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基因治疗
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DOI
高影响因子
POLYMER
·
2016
·
IF 3.586
Liao Peng,Zilin Wang,Anchao Feng,Meng Huo,Tommy Fang,Ke Wang,Yen Wei,Jinying Yuan
Research interest in electrochemical redox stimulus has grown considerably due to its easy trigger mode, in which the linkers have played important roles, such as the β-cyclodextrin-ferrocene (β-CD-Fc) linker. Star amphiphilic copolymers with well-defined and flexible structures are considered to be excellent choices for drug delivery systems (DDSs). Driven by the idea that using star polymers to improve the biocompatibility and efficiency of the β-CD-Fc-based DDS, we designed and synthesized star polymer 4 arm-poly(ε-caprolactone)-β-CD ( 4A PCL-CD ) and linear polymer polyethylene glycol-Fc ( PEG-Fc ). They can form supramolecular block copolymer 4A PCL-CD / Fc-PEG and self-assemble to micelles , which are electrochemical responsive and can be applied as drug carriers for potential controlled release, with higher efficiency and better biocompatibility compared with their linear analogues.
研究领域:
材料科学
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药物递送系统
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生物医学工程
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DOI
高影响因子
Journal of Coatings Technology and Research
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2017
·Vol. 14
·期 3
·505-516
·
IF 1.557
Huang Shan,Xiao Juan,Zhu Yan’an,Qu Jinqing
A series of multiarm star hydroxyl-terminated polyesters (MHPs) were synthesized through a “one-pot” method with di-trimethylolpropane as the core molecule, 2,2-dimethylolpropionic acid as the AB 2 -type monomer, ε-caprolactone, and monocarboxylic acids as modifiers. The influence of different monocarboxylic acids on the viscosities of polyesters and their 2K-PU films hardness was studied and it was found that MHPs prepared from lauric acid displayed the higher films hardness and lower viscosities. IR spectra of MHPs disclosed the ring-opening reaction between ε-caprolactone and hydroxyl groups occurred. 1 H NMR spectra demonstrated that the molecular structures of MHPs were irregular due to the multiplicity of reaction processes. The measured number-average molecular weights ( M
n ) of MHPs were around 715–1854 g/mol with the PDI of 1.45–2.05. MHPs exhibited lower viscosities in the range of 3304–9060 mPa s at 100% solid contents and possessed lower intrinsic viscosities compared with linear polymers of similar molecular weight. The cured films of MHPs exhibited excellent impact resistance, adhesion, flexibility, and high hardness and displayed good thermal stability with 5% weight loss at 280°C. The solution viscosities of MHPs were less than 450 mPa s at 80% solid contents, and the VOC contents of 2K-PU coatings obtained from MHPs were low to 300 g/L.
研究领域:
材料科学
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化学工程
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高影响因子
Polymer Chemistry
·
2013
·Vol. 4
·期 15
·4092-4102
·
IF 5.231
Qijing Chen,Xueteng Cao,Hao Liu,Wei Zhou,Lianjie Qin,Zesheng An
Well-defined core cross-linked star (CCS) polymers of poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) were prepared via cross-linking copolymerization in an aqueous-based dispersion polymerization system, mediated by reversible addition–fragmentation chain transfer (RAFT) polymerization. The synthesized CCS polymers were characterized by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC), dynamic light scattering (DLS), and conductivity and zeta potential measurements. The use of PDMAEMA CCS polymers as effective emulsifiers for oil-in-water emulsions was investigated. Interfacial tension measurements showed that the CCS polymer reduced the interfacial tension between water and oil in a pH-dependent manner. Gelled high internal phase emulsions (HIPEs) were formed at high oil fractions (80–89 vol%) and over a wide range of pH values (2–12). The HIPEs were characterized by conductivity, confocal laser scanning microscopy (CLSM) and rheology. The emulsion properties in terms of oil droplet size, long-term stability and rheology were pH-dependent. Complete demulsification of HIPEs was easily realized 2 min after the addition of base. The CCS-stabilized HIPEs were used as templates to prepare porous hydrophilic polymers by polymerizing the monomers in the continuous aqueous phase. The study presented herein reveals that responsive CCS polymers can be used as effective stabilizers for the formation of responsive HIPEs, which have a wide range of applications.
研究领域:
材料科学
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化学工程
·
界面化学
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高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
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2013
·Vol. 48
·期 11
·2324-2330
·
IF 1.24
Ming Cai,Xiangyang Guo,Hanhua Liang,Peilong Sun
Summary In this study, microwave-assisted extraction with ethanol (MAEE) of star anise oil from Illicium verum Hook.f . has been optimised by response surface methodology (RSM). A maximum yield of star anise oil was obtained at an optimum condition: the ratio of solvent to sample 17 mL g −1 , extraction time 16 min and microwave power 505 W. Accordingly, the highest yield of star anise oil was about 24.98%, which was much higher than that of steam distillation (SD), 7.17%. Oxygenated organic compounds in representative of trans-anethole are a major component in star anise oil, nearly 94.21% for SD and 86.66% for MAEE, identified and determined by GC-MS. The oils extracted by SD and MAEE both have strong antioxidant activities that were demonstrated by the DPPH and ABTS assays.
研究领域:
植物化学
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食品科学
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分析化学
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高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Shusu Ren,Xiang Xu,Jiyuan Sun,Haitao Zhao,Weiwei He,Lifen Zhang,Zhenping Cheng
Antimicrobial resistance is still a major clinical challenge worldwide today and the development of novel antimicrobial agents with high antimicrobial activity and low bacterial resistance is of great importance. In this work, quaternized 2-(dimethylamino) ethylmethacrylates iodonium salt-type monomers with different lengths of pendent alkyl (qDMAEMA(C x ), x = 3, 6 and 8) are synthesized for preparation of a series of cationic porphyrin-based star-shaped (co)polymers by photo-controlled bromine-iodine transformation reversible-deactivation radical polymerization (BIT-RDRP). Especially, qDMAEMA(C x ) not only acts as a monomer but also can be used as an intrinsic catalyst for the BIT-RDRP. In addition, effects of alkyl chain length (x), degree of polymerization and hydrophilic-hydrophobic balance ( H.L.B. ) on the antibacterial activity of the prepared (co)polymers are investigated. The resulting zinc ion coordinated copolymers [email protected] (qDMAEMA(C 8 ) 20 - co -PEGMA 35 ) (denoted as [email protected] ) exhibits good water solubility and is able to be absorbed effectively on the surfaces of bacteria, exhibiting excellent photodynamic inhibition activity against both S. aureus and E. coli under irradiation with 570 nm light source according to the coated plate experiments. The minimum bactericidal concentration (MBC) of [email protected] against S. aureus and E. coli are 1.5 and 2.0 μM, respectively, in the presence of light. Meanwhile, [email protected] shows quite low cytotoxicity and satisfying photolysis ability at working concentrations, displaying promising biological application prospects.
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高影响因子
Polymer Chemistry
·
2022
·Vol. 13
·期 14
·2026-2035
·
IF 5.364
Wencheng Shi,Boyu Wu,Xiaofeng Guo,Anchao Feng,San H. Thang
Fluorescent end-functional mikto-arm star copolymers were prepared by an “arm-first” approach mediated by a mixture of macro-RAFT agents. RAFT copolymerization of coumarin-POEGMA, boron-dipyrromethene (BODIPY)-PDMA and bisindolylmaleimide (BIM)-PNIPAM with different fluorophore-labeled end-groups was performed with polyethylene glycol diacrylate as a cross-linker. The fluorescence spectra of fluorophore-labeled homopolymers showed that there was a good linear correlation existing between fluorescence intensity and polymer concentration in dilute solutions. According to the fluorescence results, after carefully choosing the peaks and calculation, the arm components of star polymers can be quantitatively analyzed with obvious similarity to 1H NMR approaches which are considered to be less valid in a complicated chemical environment. Overall, it is reasonably expected that the current study expands the characterization methods for star polymers and promotes the development of the synthesis of well-defined multifunctional star polymers.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 24
·52326
·
IF 3.057
Qintian Gu,Guixiang Cheng,Bowen Ji,Jian Hu,Xibin Yue,Qiuyue Guo,Chongyang Mai,Li Yang,Chengcheng Lv,Hongwen Zhang,Yan Jiang
In this article, the titanium-oxo cluster containing bromine had been prepared by solvothermal synthesis, which was used to initiate the atom transfer radical polymerization of butyl methacrylate in order to obtain organic–inorganic hybrid materials. The structures and compositions of titanium-oxo cluster and its hybrid materials were characterized by X-ray photoelectron spectroscopy (XPS), 1 H nuclear magnetic and infrared spectra tests. The hybrid materials with different molecular weights were dissolved in tetrahydrofuran and coated on the surface of polyethylene terephthalate (PET) film, which was used to study the surface properties. Compared with 89.7% light transmittance of the pure PET film, the light transmittance of the modified films was up to 93.3%. Meanwhile, the water contact angles of the modified films also significantly increased. It would be conducive to the self-cleaning of the film surface. The coatings prepared by the static respiration diagram method had better hydrophobic effect and show the performance of light scattering. All of that could be proved through the scanning electron microscope (SEM) images. The elastic modulus and hardness of hybrid materials also change with the increase of molecular weight. In addition, the T g of the hybrid materials increased, which means they have better thermal stability than that of Polybutylmethacrylate (PBMA).
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高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2017
·
IF 4.217
Rui Liu,Wanfen Pu,James J. Sheng,Daijun Du
This work fabricated a novel star-like hydrophobically associative polyacrylamide called SHPAM used in enhanced oil recovery (EOR) processes in harsh reservoir conditions. SHPAM composed of a core of nano-silica and a layer of amphiphilic-polymeric chains was synthesized via a facile water free radical polymerization. It was systematically characterized using TEM, SEM, IR, 1 H NMR and DLS. Measurements from solubility, thickening efficiency, long-term stability and rheological performance indicated that the three-dimensional microstructure and intermolecular associations provided SHPAM solution with fantastically comprehensive properties, outperforming hydrophobically associative polyacrylamide. The evidence from rectangle cores in a serial model experiments implied that SHPAM was well compatible with permeable cores and it had desirable injectivity with sustainable mobility control in porous media. Moreover, core flooding tests revealed that after extensive water flooding, SHPAM with the concentration of 1500 mg/L increased the oil recovery factor by 20% in sandstone cores. This study showed the robust potential of SHPAM as a polymer flooding candidate in high temperature and high salinity reservoirs where harsh conditions associated with lack of fresh water constrain the applications of conventional polymers.
研究领域:
石油工程
·
高分子化学
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DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2015
·
IF 2.358
Jie Yi,Congshu Huang,Haiyan Zhuang,Hui Gong,Chuyi Zhang,Runtao Ren,Yupu Ma
The star-shaped polyester polyols based on initiators (trimethylolpropane or pentaerythritol) and ɛ-caprolactone were prepared by polycondensation reaction. The degradable polyurethane (PU) films were prepared by mixing star-shaped polyester polyols and crosslinker agent (hexamethylene diisocyanate trimer). The hydrolytic degradation and water absorption experiments demonstrated that the PU films could erode in artificial sea water, which were controlled by varying the ratios of ɛ-caprolactone/trimethylolpropane and the arm number of star-shaped polyester polyols. The mechanical properties of PU films and coatings increased with decreasing the ratios of ɛ-caprolactone/trimethylolpropane and increasing the arm number of star-shaped polyester polyols. The surfaces of PU films and coatings kept eroding, which were revealed by scanning electron microscopy. The copper ion release rates from PU coatings reached steady state at about 31 days. The marine field tests of PU coatings demonstrated that the degradable PU coatings based on star-shaped polyester polyols were effective coatings for marine antifouling.
研究领域:
材料科学
·
海洋生物学
·
化学工程
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DOI
高影响因子
FOOD CONTROL
·
2026
·
IF 7
Xiangmin Kuang,Qingbo Huang,Jiapeng Wu,Sakamon Devahastin,Chaofan Guo,Yongli Jiang,Junjie Yi
Pesticide residues on dried star anise remain major barrier to product safety and quality; current washing practices unfortunately fail to balance decontamination efficiency with retention of bioactive compounds. Suitability of emerging decontamination media, in particular alkaline electrolyzed water (ALEW), for star anise has nevertheless not been assessed. The present study therefore compared use of ALEW with use of conventional methods at ambient and high-temperature conditions to decontaminate star anise; four representative fungicides were tested. Quality of dried star anise was then determined in terms of color, rehydration behavior, shikimic acid and volatile oil contents. ALEW treatment at ambient temperature provided superior pesticide reduction (9.3–14.7%) compared with other treatments; such treatment also led to enhanced rehydration capacity and color. Unexpectedly, high-temperature soaking markedly reduced effectiveness of ALEW and caused significant losses of shikimic acid and volatile oils. Machine learning modeling identified support vector regression as most accurate tool to predict influences of pH, soaking temperature and soaking time of ALEW on pesticide residues decontamination and reveals distinct parameter sensitivities among different pesticides. Short-duration, ambient ALEW treatment offers practical and quality-preserving solution for pesticide control in star anise processing, with clear implications for sustainable spice manufacturing.
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高影响因子
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