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351.
Silvana Maione Georgina Fabregat Luis J. del Valle Anca‐Dana Bendrea Luminita Cianga Ioan Cianga Francesc Estrany Carlos Alemán 《Journal of Polymer Science.Polymer Physics》2015,53(4):239-252
Graft copolymers formed by anchoring poly(ethylene glycol) (PEG) chains to conjugated polythiophene have been prepared by copolymerizing two compounds: unsubstituted α‐terthiophene (Th3) and a thiophene‐derived macromonomer having an α‐terthiophene conjugated sequence and one Th3 bearing a PEG chain with molecular weight of 2000 as substitute at the 3‐position of the central heterocycle (Th3‐PEG2000). The grafting ratio of the resulting copolymers (PTh3*‐g‐PEG), which were obtained using 75:25 and 50:50 Th3‐PEG2000:Th3 weight ratios, is significantly smaller than that of copolymers derived from polymerization of macromonomers consisting of a α‐pentathiophene sequence in which the central ring bears a PEG chain of Mw = 2000 (PTh5‐g‐PEG). The electroactivity and electrochemical stability of PTh3*‐g‐PEG is not only higher than that of PTh5‐g‐PEG but also higher than that of PTh3, the latter presenting a very compact structure that makes difficult the access and escape of dopant ions into the polymeric matrix during the redox processes. Furthermore, the optical π‐π* lowest transition energy of PTh3*‐g‐PEG is lower than that of both PTh5‐g‐PEG and PTh3. These properties, combined with suitable wettability and roughness, result in an excellent behavior as bioactive platform of PTh3*‐g‐PEG copolymers, which are more biocompatible, in terms of cellular adhesion and proliferation, and electro‐compatible than PTh5‐g‐PEG. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 239–252 相似文献
352.
353.
Synthesis,physicochemical characteristics,and biocompatibility of self‐assemble polymers bearing guanine,cytosine, uracil,and thymine moieties
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Jungwoon Jung Jinseok Lee Brian J. Ree Heesoo Kim Ik Jung Kim Jung Ran Kim Moonhor Ree 《Journal of polymer science. Part A, Polymer chemistry》2015,53(9):1151-1160
We synthesized chemically well‐defined brush (i.e., comb‐like) polymers bearing guanine, cytosine, uracil, or thymine moieties at the bristle ends. The polymers were stable up to 220 °C and were readily solution‐processable, yielding high‐quality films. Interestingly, the brush polymers favorably self‐assembled to form molecular multibilayer structures stabilized by hydrogen bonding interactions among the nucleobase moieties at the bristle ends, which provided nucleobase‐rich surfaces. The multibilayer‐structured polymer films showed high water affinity. They also displayed selective protein adsorption, suppressed bacterial adherence, facilitated cell adhesion, and exhibited good biocompatibility in mice. The brush polymer DNA‐mimicking comb‐like polymers are suitable as biomaterials and in protein separation applications. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1151–1160 相似文献
354.
Bioreducible hyperbranched polyglycerols with disulfide linkages: Synthesis and biocompatibility evaluation
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Rajesh A. Shenoi Irina Chafeeva Benjamin F. L. Lai Sonja Horte Jayachandran N. Kizhakkedathu 《Journal of polymer science. Part A, Polymer chemistry》2015,53(18):2104-2115
In this article, we describe the development of multifunctional, water‐soluble hyperbranched polyglycerols containing redox‐sensitive disulfide linkages as a new class of biodegradable polymers. The polymers were synthesized by the anionic ring opening multibranching (co)polymerization of glycidol with an epoxide monomer bearing disulfide groups, 2‐((2‐oxiran‐2‐ylmethoxy)ethyl)disulfanyl) ethan‐1‐ol. Polymerizations were optimized at 65 °C unlike the homopolymerization of glycidol. Both low (5–10 kDa) and high (100 kDa) molecular weight polymers were synthesized in a controlled manner with low polydispersity. The polymers underwent degradation in presence of reducing agents such as tris(2‐carboxyethyl)phosphine, dithiothreitol, and glutathione resulting in low molecular weight fragments with thiol groups. Blood compatibility analysis using coagulation, platelet activation, complement activation and red blood cell lysis assays as well as cell toxicity analysis using MTS assay revealed the excellent biocompatibility of these newly synthesized polymer architectures. All these features make these polymers suitable for intracellular delivery of therapeutic molecules. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2104–2115 相似文献
355.
Tiantang Fan Jingwen Qin Shengli Lin Wuyou Ye Qing Liu Zhongyong Fan Ye Wang 《先进技术聚合物》2020,31(8):1675-1687
The blends of poly(1,3‐trimethylene carbonate‐b‐(l ‐lactide‐ran‐glycolide)) (PTLG) with poly(d ‐lactide) (PDLA) were prepared via solution‐casting method using CH2Cl2 as solvent. The poly(l ‐lactide) (PLLA) segments of PTLG with PDLA chain constructed as stereocomplex structures and growth stereocomplex crystals of PLA (sc‐PLA). The effects of sc‐PLA crystals on thermal behavior, mechanical properties, thermal decomposition of the PTLG/PDLA blends were investigated, respectively. The differential scanning calorimetry (DSC) and wide‐angle X‐ray diffraction (WAXD) results showed that the total crystallinity of the PTLG/PDLA blends was increased with the PDLA content increasing. Heterogeneous nucleation of sc‐PLA crystals induced crystallization of the PLLA segments in PTLG. The crystallization temperature of samples shifted to 107.5°C for the PTLG/PDLA‐20 blends compared with that of the PTLG matrix, and decreased the half‐time of crystallization. The mechanical measurement results indicated that the tensile strength of the PTLG/PDLA blends was improved from 21.1 MPa of the PTLG matrix to 39.5 MPa of PTLG/PDLA‐20 blends. The results of kinetics of thermal decomposition of the PTLG/PDLA blends by TGA showed that the apparent activation energy of the PTLG/PDLA blends was increased from 59.1 to 72.1 kJ/mol with the increasing of the PDLA content from 3 wt% to 20 wt%, which indicated the enhancement of thermal stability of the PTLG/PDLA blends by addition of PDLA. Furthermore, the biocompatibility of the PTLG/PDLA blends cultured with human adipose‐derived stem cells was evaluated by CCK‐8 and live/dead staining. The experiment results proved the PTLG/PDLA blends were a kind of biomaterial with excellent physical performances with very low cytotoxicity. 相似文献
356.
Tailoring Fluorescence Emission of Diketopyrrolopyrrole Dyes by an Aggregation‐induced Emission Coupled Excited‐state Intramolecular Proton Transfer Process
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Dr. Fuyong Wu Prof. Lingyun Wang Prof. Hao Tang Prof. Derong Cao Prof. Xiaofang Jiang 《化学:亚洲杂志》2018,13(8):950-954
Two diketopyrrolopyrrole derivatives ( DPP1 and DPP2 ) are used for generating multiple luminescent colors (yellow–orange–red–deep red) in solution, nanoparticle, aggregate and solid states through an aggregation‐induced emission (AIE) coupled excited‐state intramolecular proton transfer (ESIPT) process. They are potentially useful for bioimaging due to their good biocompatibility and large Stoke shifts. 相似文献
357.
Judit E. Puskas Yaohong Chen Yaser Dahman Donna Padavan 《Journal of polymer science. Part A, Polymer chemistry》2004,42(13):3091-3109
This article highlights the biomaterial‐related research of the Macromolecular Engineering Research Centre (MERC). The MERC group concentrated on polyisobutylene (PIB)‐based biomaterials. In this article, first the unique properties of PIB are discussed, followed by a review of PIB‐based potential biomaterials. MERC's systematic research program aimed to develop novel PIB‐based biomaterials is then highlighted, including surface modification and biocompatibility studies. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3091–3109, 2004 相似文献
358.
Shixian Li Chunnuan Ye Guangdong Zhao Meijing Zhang Youliang Zhao 《Journal of polymer science. Part A, Polymer chemistry》2012,50(15):3135-3148
Symmetric reduction‐responsive amphiphilic comblike copolymers mid‐disulfide‐functionalized comblike copolymers with alternating copolymer comprised of styrenic unit and N‐(2‐hydroxyethyl) maleimide (HEMI) unit (poly(St‐alt‐HEMI)) backbones and alternating PEG and PCL side chains (S‐CP(PEG‐alt‐PCL)) with poly(St‐alt‐HEMI) backbones and alternating poly(ε‐caprolactone) (PCL) and poly(ethylene glycol) (PEG) side chains were synthesized and used as nanocarriers for in vitro release of doxorubicin. The target copolymers with predetermined molecular weight and narrow molecular weight distribution (Mw/Mn = 1.15–1.20) were synthesized by reversible addition‐fragmentation chain transfer (RAFT) copolymerization of vinylbenzyl‐terminated PEG and N‐(2‐hydroxyethyl) maleimide mediated by a disulfide‐functionalized RAFT agent S‐CPDB, and followed by ring‐opening polymerization of ε‐caprolactone. When compared with linear block copolymer comprised of poly(ethylene glycol) (PEG) and poly(?‐caprolactone) (PCL) segments (PEG‐b‐PCL) copolymers, comblike copolymers with similar PCL contents usually exhibited decreased crystallization temperature, melting temperature, and degree of crystallinity, indicating the significant influence of copolymer architecture on physicochemical properties. Dynamic light scattering measurements revealed that comblike copolymers were liable to self‐assemble into aggregates involving vesicles and micelles with average diameter in the range of 56–226 nm and particle size distribution ranging between 0.07 and 0.20. In contrast to linear copolymer aggregates, comblike copolymer aggregates with similar compositions were of improved storage stability and enhanced drug‐loading efficiency. In vitro drug release confirmed the disulfide‐linked comblike copolymer aggregates could rapidly release the encapsulated drug when triggered by 10 mM DL ‐dithiothreitol. These reduction‐sensitive, biocompatible, and biodegradable aggregates have a potential as controlled delivery vehicles. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
359.
360.
Věra Kašpárková Petr Humpolíček Jaroslav Stejskal Jitka Kopecká Zdenka Kuceková Robert Moučka 《先进技术聚合物》2016,27(2):156-161
Understanding the correlation between the preparation, purification, impurity leaching, and cytotoxicity of polyaniline is crucial for the application of this conducting polymer in biomedicine. Polyaniline hydrochloride was purified in a Soxhlet extractor by using six different solvents: methanol, 1,2‐dichloroethane, acetone, ethyl acetate, hexane, or 0.2 M aqueous hydrochloric acid. The chromatographic analyses of impurities leached out of the polymer into the solvents confirmed differences in impurity profiles, which depended on the polarity of the extraction solvent. Compared with the original polymer, the conductivity of purified polyanilines increased in dependence on the amount and type of extracted impurities. The cytotoxicity of purified samples determined on the mouse embryonic fibroblast cell line NIH/3T3 using MTT assay improved as well. Methanol and 0.2 M hydrochloric acid were the most efficient solvents capable of extracting low‐molecular‐weight impurities, and thus reducing polyaniline cytotoxicity. The absence of cytotoxicity was observed at an extract concentration of 10%. Extraction with suitable solvents can, therefore, be a possible way of obtaining cyto‐compatible polyaniline with sufficient conductivity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献