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A Novel Initiator Containing Alkyne Group for the Polymerization of 2-Ethyl-2-oxazoline
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作者 Muhammad Waqas Ali 高亚婷 +1 位作者 Muhammad Siddiq 叶晓东 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第1期77-84,I0002,共9页
A novel trifunctional initiator with one alkyne and two trifluoromethanesulfonate moieties was synthesized from a protected alcohol 5-hydroxyl-2-phenyl-1, 3-dioxane. The alkyne func- tionalized intermediate with two p... A novel trifunctional initiator with one alkyne and two trifluoromethanesulfonate moieties was synthesized from a protected alcohol 5-hydroxyl-2-phenyl-1, 3-dioxane. The alkyne func- tionalized intermediate with two protected alcohol groups was synthesized by reacting with propargyl bromide. The alcohol groups were cleaved using a mixture of tetrahydrofuran and hydrochloric acid aqueous solution. In the last step the initiator was synthesized us- ing triflic anhydride in carbon tetrachloride. The initiator was characterized by 1H NMR and used for the polymerization of 2-ethyl-2-oxazoline which gives polymers with narrow distribution. For comparison a similar initiator with two tosylates was prepared and used for the polymerization of the monomer 2-ethyl-2-oxazoline, the resulting product has a wide molecular weight distribution and most of the initiator remains unreacted after 24 h which may be due to the steric hindrance between the two tosylate groups. To further explore the steric hindrance phenomenon, a linear tosylate initiator was synthesized, but still some of the initiator remains unreacted, illustrating that both steric hindrance and electrophilic balance affect the efficiency of the cationic ring-opening polymerization. All of the polymers were characterized in detail by using IH NMR, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy, and size exclusion chromatography to confirm the purity and distribution of the polymers. 展开更多
关键词 ELECTROPHILE 2-Ethyl-2-oxazoline Steric hindrance TRIFLATE
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Nucleobase-crosslinked poly(2-oxazoline) nanoparticles as paclitaxel carriers with enhanced stability and ultra-high drug loading capacity for breast cancer therapy 被引量:2
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作者 Si Dong Sheng Ma +3 位作者 Hongyu Chen Zhaohui Tang Wantong Song Mingxiao Deng 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第4期571-582,共12页
Poly(2-oxazoline)(POx)has been regarded as a potential candidate for drug delivery carrier to meet the challenges of nanomedicine clinical translation,due to its excellent biocompatibility and self-assembly properties... Poly(2-oxazoline)(POx)has been regarded as a potential candidate for drug delivery carrier to meet the challenges of nanomedicine clinical translation,due to its excellent biocompatibility and self-assembly properties.The drug loading capacity and stability of amphiphilic POxs as drug nanocarriers,however,tend to be insufficient.Herein,we report a strategy to prepare nucleobase-crosslinked POx nanoparticles(NPs)with enhanced stability and ultra-high paclitaxel(PTX)loading capacity for breast cancer therapy.An amphiphilic amine-functionalized POx(PMBEOx-NH_(2))was firstly prepared through a click reaction between cysteamines and vinyl groups in poly(2-methyl-2-oxazoline)-block-poly(2–butyl–2-oxazoline-co-2-butenyl-2-oxazoline)(PMBEOx).Complementary nucleobase-pairs adenine(A)and uracil(U)were subsequently conjugated to PMBEOx-NH2 to give functional POxs(POxA and POxU),respectively.Due to the nucleobase interactions formed between A and U,NPs formed by POxA and POxU at a molar ratio of 1:1 displayed ultrahigh PTX loading capacity(38.2%,PTX/POxA@U),excellent stability,and reduced particle size compared to the uncross-linked PTX-loaded NPs(PTX/PMBEOx).Besides the prolonged blood circulation and enhanced tumor accumulation,the smaller PTX/POxA@U NPs also have better tumor penetration ability compared with PTX/PMBEOx,thus leading to a higher tumor suppression rate in two murine breast cancer models(E0711 and 4T1).These results proved that the therapeutic effect of chemotherapeutic drugs could be improved remarkably through a reasonable optimization of nanocarriers. 展开更多
关键词 poly(2-oxaozoline) NANOPARTICLES PACLITAXEL Nucleobase-crosslinked Murine breast cancer
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Delivery of docetaxel using pH-sensitive liposomes based on D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate:Comparison with PEGylated liposomes
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作者 Shu Han Ruiyang Sun +4 位作者 Hong Su Jing Lv Huan Xu Di Zhang Yuanshan Fu 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第4期391-404,共14页
This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC... This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC, FTIR, and ~1H-NMR. The buffering capacity of polyethylene glycol-distearoyl phosphatidylethanolamine(PEG-DSPE) and TPOS was determined by acid-base titration, and TPOS displayed a slower downtrend and gentler slope of titration curve than PEG-DSPE within pH 7.4–5.0. Studies on the in vitro drug release demonstrated that TPOS modified docetaxel(DOC) liposomes(TPOS-DOC-L) had a slower drugrelease rate at pH 7.4 similar to PEGylated-DOC liposomes(PEG-DOC-L), whereas the release rate reached approximately 86.92% ± 1.69% at pH 6.4. In vitro cellular uptake assays by microplate reader, and flow cytometry revealed that TPOS modified coumarin 6 liposomes(TPOS-C6-L) had stronger cellular uptake at pH 6.4 than that at pH 7.4( P < 0.01). Conversely, for PEGylated C6 liposomes(PEG-C6-L) and conventional C6 liposomes(C6-L), very similar cellular uptakes were exhibited at different pH values. Confocal laser scanning microscopy images showed that PEG-C6-L and C6-L were mainly located in lysosomes. By contrast, TPOS-C6-L showed broader cytoplasmic release and distribution at 4 h. MTT assay showed that the cytotoxicity of TPOS-DOC-L was similar to that of PEG-DOC-L and conventional DOC liposomes(DOC-L) at the same DOC concentration and at pH 7.4, but was much lower than those at pH 6.4 after 48 h of incubation. The apoptosis of PEG-DOC-L and DOC-L had no remarkable improvement with decreased pH from 7.4 to 6.4. Meanwhile, TPOS-DOC-Lsignificantly induced the apoptosis of HeLa cells with decreased pH. Therefore, TPOS can be a biomaterial for the construction of a pH-sensitive drug delivery system. 展开更多
关键词 d-α-tocopheryl poly(2-ethyl-2-oxazoline) SUCCINATE Liposomes PH-SENSITIVE PEGYLATION
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MECHANISM-TRANSFORMATION SYNTHESIS AND CHARACTERIZATION OF POLY(STYRENE-b-2-ETHYL-2-OXAZOLINE) DIBLOCK COPOLYMER
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作者 Sheng-qing Xu Han-ying Zhao +1 位作者 Tao Tang Bao-tong Huang Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第2期145-150,共6页
By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with e... By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with ethylene oxide and its tosylation; the second step is the cationic ring-opening polymerization of 2-ethyl-2-oxazoline. The products were thoroughly characterized by various methods, such as H-1-NMR, IR, DMA, TEM and SAXS. The results show that the copolymer obtained possesses high molecular weight and narrow molecular weight distribution. 展开更多
关键词 diblock copolymer mechanism-transformation polymerization 2-ethyl-2-oxazoline STYRENE characterization
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Multiblock poly(ether-b-amide)copolymers comprised of PA1212 and PPO-PEO-PPO with specific moisture-responsive and antistatic properties 被引量:1
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作者 Jie Jiang Wei Cheng +5 位作者 Qiuyu Tang Xun Pan Jinjin Li Ling Zhao Zhenhao Xi Weikang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期421-430,共10页
Functional multiblock poly(ether-b-amide)(PEBA)copolymers,comprised of PA1212(polyamide 1212)as hard segments and Jeffamine ED-2003 as soft segments,were successfully prepared via two-step melt polycondensation withou... Functional multiblock poly(ether-b-amide)(PEBA)copolymers,comprised of PA1212(polyamide 1212)as hard segments and Jeffamine ED-2003 as soft segments,were successfully prepared via two-step melt polycondensation without any amidation catalyst.Here,using diamino-terminated poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide)(PPO-PEO-PPO),Jeffamine ED-2003,enhances the compatibility between polyamide oligomer and polyether,which is better than the traditional route using hydroxyl-terminated polyether.The chemical structure of multiblock PEBAs,as well as the microphase separated structure with crystalline phase of polyamide and polyether,were confirmed by heteronuclear multiple-bond correlation spectrum,heteronuclear multiple quantum correlation spectrum,Fourier transform infrared spectroscopy(FT-IR),differential scanning calorimetry and dynamic mechanical analysis.The hydrophilic PEBA copolymers showed water adsorption ranging from 87.3%to 17.1%depending on the polyether content,and specially showed moisture responsive behavior within seconds when exposed to moisture.The corresponding mechanism was studied using time-resolved attenuated total reflectance FT-IR spectroscopy in the molecular level and the water diffusion coefficient was estimated to be 1.07×10^(–8)cm^(2)∙s^(-1).Two-dimensional correlation FT-IR spectra analysis was performed to confirm that the interaction between water and polyether phase was in preference to that between water and polyamide matrix,and water molecule only forms hydrogen bond with the polyether segment.Due to the incorporation of PEO segments,the PEBAs have the surface resistivity varying from 5.6×10^(9)to 6.5×10^(10)Ω,which makes PEBA potential candidate as permanent antistatic agent. 展开更多
关键词 poly(ether-b-amide)s Moisture-responsive Antistatic In situ FT-IR 2D FT-IR analysis
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Mesoporous poly(ionic liquid)s with dual active sites for highly efficient CO_(2)conversion 被引量:1
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作者 Yawen Fu Yanan Xu +11 位作者 Zepeng Zeng Abdul-Rauf Ibrahim Jin Yang Shuliang Yang Yaqiang Xie Yanzhen Hong Yuzhong Su Hongtao Wang Yanliang Wang Li Peng Jun Li Wendy L.Queen 《Green Energy & Environment》 SCIE EI CSCD 2023年第2期478-486,共9页
Atmospheric CO_(2)concentrations are soaring due to the continued use of fossil fuels in energy production,an anthropogenic activity that is playing a leading role in global warming.Thus,research aimed at the capture ... Atmospheric CO_(2)concentrations are soaring due to the continued use of fossil fuels in energy production,an anthropogenic activity that is playing a leading role in global warming.Thus,research aimed at the capture and conversion of CO_(2)into value-added products,such as cyclic carbonates,is booming.While CO_(2)is an abundant,cheap,non-toxic,and readily accessible Cl feedstock,its thermodynamic stability necessitates the development of highly efficient catalysts that are able to promote chemical reactions under mild conditions.In this work,a novel mesoporous poly(ionic liquid)with dual active sites was synthesized through a facile method that involves co-polymerization,post-synthetic metalation,and supercritical CO_(2)drying.Due to a high density of nucleophilic and electrophilic sites,the as-prepared poly(ionic liquid),denoted as P2D-4BrBQA-Zn,offers excellent performance in a CO_(2)cycloaddition reaction using epichlorohydrin as the substrate(98.9%conversion and 96.9%selectivity).Moreover the reaction is carried out under mild,solvent-free,and additive-free conditions.Notably,P2D-4BrBQA-Zn also efficiently promotes the conversion of various other epoxide substrates into cyclic carbonates.Overall,the catalyst is found to have excellent substrate compatibility,stability,and recyclability. 展开更多
关键词 Mesoporous poly(ionic liquid) Nucleophile/electrophilic sites Carbon dioxide cycloaddition Heterogeneous catalysis Supercritical CO_(2)drying
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包封骨形态发生蛋白2的不同相对分子质量聚乳酸-聚乙醇酸共聚物微囊促进成骨效果的研究
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作者 袁莉红 陈晨 +1 位作者 马语笛 梁睿贞 《华西口腔医学杂志》 CAS CSCD 北大核心 2024年第5期572-580,共9页
目的 探索不同相对分子质量聚乳酸-聚乙醇酸共聚物(PLGA)微囊包封骨形态发生蛋白2 (BMP-2)对成骨细胞骨形成能力的影响。方法 用双通道微量注射泵制备包封BMP-2的2种相对分子质量(12 000和30 000)的PLGA微囊。用光学显微镜及扫描电子显... 目的 探索不同相对分子质量聚乳酸-聚乙醇酸共聚物(PLGA)微囊包封骨形态发生蛋白2 (BMP-2)对成骨细胞骨形成能力的影响。方法 用双通道微量注射泵制备包封BMP-2的2种相对分子质量(12 000和30 000)的PLGA微囊。用光学显微镜及扫描电子显微镜(SEM)观察微囊形态结构;磷酸盐缓冲溶液浸泡法表征微囊缓释性能;细胞Calcein-AM/PI染色及CCK-8法检测微囊细胞相容性;Transwell迁移实验检测包封BMP-2的微囊作用48 h对MC3T3-E1细胞的趋化作用;碱性磷酸酶活力测定、茜素红染色法检测微囊作用MC3T3-E1细胞后对细胞骨形成能力的影响。结果 2种相对分子质量的微囊均表面光滑,具有良好的细胞相容性。相对分子质量12 000的微囊的趋化作用最佳。相对分子质量30 000的微囊较相对分子质量12 000的微囊缓释时间长,且初始爆发量减少了约25%。成骨诱导14、21 d后,相对分子质量30 000的微囊形成的钙沉积结节较相对分子质量12 000的微囊多。结论 本研究通过调控PLGA的相对分子质量控制BMP-2的释放,发现相对分子质量30 000的微囊能够更好地诱导MC3T3-E1细胞的长期骨形成能力。 展开更多
关键词 聚乳酸-聚乙醇酸共聚物微囊 骨形态发生蛋白2 成骨
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基于CO_(2)促进传输的抗凝血非对称PMP膜的构建及其性能研究
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作者 田懿 朱怡学 +4 位作者 童霄 王敏洁 贾桂玲 陈大竞 黄小军 《膜科学与技术》 CAS CSCD 北大核心 2024年第3期38-48,共11页
新冠疫情期间,为重症患者的心肺功能提供短暂支持的ECMO仪器对人类尤为重要,但其核心组件氧合膜材料被3M公司全球垄断.PMP(聚-4-甲基-1-戊烯)由于具有较为优异的气体渗透能力和生物相容性,在氧合器膜材料中有着巨大的潜力.本文通过TIPs... 新冠疫情期间,为重症患者的心肺功能提供短暂支持的ECMO仪器对人类尤为重要,但其核心组件氧合膜材料被3M公司全球垄断.PMP(聚-4-甲基-1-戊烯)由于具有较为优异的气体渗透能力和生物相容性,在氧合器膜材料中有着巨大的潜力.本文通过TIPs法制备PMP中空纤维膜,并以此作为基材通过静电作用力驱动的层层自组装在表面引入PEI和肝素组成的正负电荷改性层,制备了具有非对称结构的PMP复合膜并研究了改性条件对复合膜表面结构组成和气体传输、血液相容性等性能的影响.结果表明,通过层层自组装引入的PEI-肝素改性层极大地提高了PMP中空纤维复合膜的气体传输性能和血液相容性,使其在气体分离、膜式氧合等领域具有了重要的应用潜力. 展开更多
关键词 聚-4-甲基-1-戊烯(PMP) 层层自组装 抗凝血非对称 CO_(2)气体传输
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Novel sandwich structured glass fiber Cloth/Poly(ethylene oxide)-MXene composite electrolyte
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作者 Yu-Qin Mao Guang-He Dong +3 位作者 Wei-Bin Zhu Yuan-Qing Li Pei Huang Shao-Yun Fu 《Nano Materials Science》 EI CAS CSCD 2024年第1期60-67,共8页
Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performa... Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performance all-solid-state lithium metal batteries.In this article,a novel sandwich structured solid-state PEO composite electrolyte is developed for high performance all-solid-state lithium metal batteries.The PEO-based composite electrolyte is fabricated by hot-pressing PEO,LiTFSI and Ti_(3)C_(2)T_(x) MXene nanosheets into glass fiber cloth(GFC).The as-prepared GFC@PEO-MXene electrolyte shows high mechanical properties,good electrochemical stability,and high lithium-ion migration number,which indicates an obvious synergistic effect from the microscale GFC and the nanoscale MXene.Such as,the GFC@PEO-1 wt%MXene electrolyte shows a high tensile strength of 43.43 MPa and an impressive Young's modulus of 496 MPa,which are increased by 1205%and 6048%over those of PEO.Meanwhile,the ionic conductivity of GFC@PEO-1 wt%MXene at 60℃ reaches 5.01×10^(-2) S m^(-1),which is increased by around 200%compared with that of GFC@PEO electrolyte.In addition,the Li/Li symmetric battery based on GFC@PEO-1 wt%MXene electrolyte shows an excellent cycling stability over 800 h(0.3 mA cm^(-2),0.3 mAh cm^(-2)),which is obviously longer than that based on PEO and GFC@PEO electrolytes due to the better compatibility of GFC@PEO-1 wt%MXene electrolyte with Li anode.Furthermore,the solid-state Li/LiFePO_(4) battery with GFC@PEO-1 wt%MXene as electrolyte demonstrates a high capacity of 110.2–166.1 mAh g^(-1) in a wide temperature range of 25–60C,and an excellent capacity retention rate.The developed sandwich structured GFC@PEO-1 wt%MXene electrolyte with the excellent overall performance is promising for next generation high performance all-solid-state lithium metal batteries. 展开更多
关键词 Solid polymer electrolyte Ti_(3)C_(2)T_(x)MXene poly(ethylene oxide) Glass fiber cloth All-solid-state Li metal Battery
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Low testing rates and high BRCA prevalence: Poly (ADP-ribose) polymerase inhibitor use in Middle East BRCA/homologous recombination deficiency-positive cancer patients
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作者 Naveed Syed Ashish Vittalrao Chintakuntlawar +6 位作者 Deepti Vilasini Aisha Mohamed Al Salami Riad Al Hasan Imrana Afrooz Kanishka Uttam Chandani Ashok Uttam Chandani Aref Chehal 《World Journal of Clinical Oncology》 2024年第7期848-858,共11页
BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breas... BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer.They are also effective for new and recurrent ovarian cancers that are BRCA-or homologous recombination deficiency(HRD)-positive.However,data on these mutations and PARPi use in the Middle East are limited.AIM To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.METHODS This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations,and 25 of 65 ovarian cancer patients tested for HRD.These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023.Data were summarized using descriptive statistics and compared using counts and percentages.Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.RESULTS Among the 472 breast cancer patients,12.1%underwent BRCA testing,and 38.5%of 65 ovarian cancer patients received HRD testing.Pathogenic mutations were found in 25.6%of the tested patients:26.3%breast cancers had germline BRCA(gBRCA)mutations and 24.0%ovarian cancers showed HRD.Notably,40.0%of gBRCA-positive breast cancers and 66.0%of HRD-positive ovarian cancers were Middle Eastern and Asian patients,respectively.PARPi treatment was used in 5(33.3%)gBRCA-positive breast cancer patients as first-line therapy(n=1;7-months progression-free),for maintenance(n=2;>15-months progression-free),or at later stages due to compliance issues(n=2).Four patients(66.6%)with HRD-positive ovarian cancer received PARPi and all remained progression-free.CONCLUSION Lower testing rates but higher BRCA mutations in breast cancer were found.Ethnicity reflected United Arab Emirates demographics,with breast cancer in Middle Eastern and ovarian cancer in Asian patients. 展开更多
关键词 Homologous recombination repair BRCA1 BRCA2 Homologous recombination deficiency Ovarian cancer Breast cancer poly(ADP-ribose)polymerase inhibitors OLAPARIB DNA double-strand breaks
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Advancements in Polymer Science: Synthesis, Characterization, and Biomedical Applications of Homopolymers and Copolymers
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作者 Anaif M. Alhewaitey Ishrat Khan Emmanuel Ramsey Buabeng 《Open Journal of Polymer Chemistry》 2024年第3期167-198,共32页
Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copo... Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copolymers is fundamental to advancing polymer research and development. In this comprehensive review, we explore various preparation methods, including free radical, anionic, and cationic polymerization, utilized for synthesizing homopolymers and copolymers. Furthermore, we investigate solvent choices commonly employed for polymer characterization, ranging from neat conditions, polar protic and polar aprotic solvents. We also explored characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). In addition to industrial applications, we highlight the diverse biological applications of homopolymers, poly(2-hydroxyethyl methacrylate) (pHEMA) and polystyrene, which find its extensive use in biomedicine. By synthesizing and analyzing this wealth of information, this review aims to provide a comprehensive understanding of the synthesis, characterization, and applications of homopolymers and copolymers, with a particular focus on their biological applications. This holistic approach not only contributes to advancements in polymer science and technology but also fosters innovation in biomedicine, ultimately benefiting human health and well-being. 展开更多
关键词 HOMOpolyMER COpolyMER poly(2-hydroxyethyl methacrylate) (pHEMA) polystyrene Free Radical polymerization Atomic Force Microscopy Solvent Polarity
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PARP1通过调控POU2F2的表达促进肝细胞癌的进展研究
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作者 温自强 兰军良 +1 位作者 周博 许其威 《中国癌症杂志》 CAS CSCD 北大核心 2024年第9期848-856,共9页
背景与目的:肝细胞癌(hepatocellular carcinoma,HCC)是严重威胁人类健康的重大疾病。多腺苷二磷酸核糖聚合酶1[poly(ADP-ribose)polymerase 1,PARP1]作为一种腺苷二磷酸核糖转移酶,能够促进DNA损伤修复进程,因此,PARP1通常被看作是一... 背景与目的:肝细胞癌(hepatocellular carcinoma,HCC)是严重威胁人类健康的重大疾病。多腺苷二磷酸核糖聚合酶1[poly(ADP-ribose)polymerase 1,PARP1]作为一种腺苷二磷酸核糖转移酶,能够促进DNA损伤修复进程,因此,PARP1通常被看作是一种促癌基因,但其在HCC中的表达和机制尚不明确。本研究旨在探讨PARP1在HCC患者中的表达趋势及其在HCC发生、发展中的作用。方法:首先,通过对癌症基因组图谱(The Cancer Genome Atlas,TCGA)和临床蛋白质组学癌症分析联盟(Clinical Proteomic Tumor Analysis Consortium,CPTAC)HCC数据库的分析鉴定PARP1的临床表达情况,采用实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)和蛋白质印迹法(Western blot)检测PARP1在HCC患者癌组织及癌旁组织样本中的表达情况。然后,借助PARP1的抑制剂PJ34抑制PARP1酶活性,同时借助小RNA干扰技术下调HCC细胞系中PARP1的表达,并以此为模型,采用细胞计数试剂盒-8(cell counting kit-8,CCK-8)和流式细胞术检测PARP1对细胞活力的影响,采用RTFQ-PCR检测HCC细胞干性基因的表达变化,采用细胞迁移和侵袭实验检测HCC细胞迁移和侵袭能力。采用生物信息学方法分析HCC进展中受PARP1调控的靶基因及其参与通路,并通过回补实验确定PARP1靶基因是否参与HCC细胞恶性表型。结果:在TCGA和CPTAC数据库中,PAPR1的表达均在HCC组中显著上调。RTFQ-PCR和Western blot检测结果表明,相比癌旁组织,HCC组织中的PARP1在转录和翻译水平均显著上调。生存分析结果表明,PARP1的表达与HCC患者的预后呈显著负相关。CCK-8、流式细胞术、RTFQ-PCR、细胞迁移及侵袭实验结果显示,在HCC细胞中下调PARP1表达可以抑制HCC细胞增殖,降低HCC细胞活性及干性,并减弱HCC细胞迁移和侵袭能力。生物信息学分析提示,PARP1调控基因富集在核因子κB(nuclear factor-κB,NF-κB)和Necroptosis通路中,POU2类同源框2(POU class homeobox 2,POU2F2)可能是PARP1的潜在靶基因。相关性分析、RTFQ-PCR和Western blot检测一致证实POU2F2的表达受到PARP1的调控,但PJ34不能抑制POU2F2的表达。CCK-8、流式细胞术和RTFQ-PCR结果显示,采用共转染的方式在敲低PARP1的HCC细胞系中回补POU2F2可以增强HCC细胞增殖能力,提高HCC细胞活性,促进HCC细胞干性。结论:PARP1可以通过非酶活性正向调控POU2F2表达促进HCC细胞恶性表型,本研究结果有望为HCC的临床治疗和新药开发提供新的思路。 展开更多
关键词 肝细胞癌 多腺苷二磷酸核糖聚合酶1 POU2类同源框2 增殖 活性 干性
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面向凝聚态核磁共振的新型NaKV_(4)O_(9)·2H_(2)O材料与多铁性材料的物性研究
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作者 谷瑞新 《佳木斯大学学报(自然科学版)》 CAS 2024年第1期169-172,共4页
近年来凝聚态物理领域中,学者逐渐利用更加先进的技术,如核磁共振技术对不同材料进行更加详细的研究。因此研究利用凝聚态核磁共振技术对新型NaKV_(4)O_(9)·2H_(2)O材料与多铁性材料CuBr_(2)的物理性质进行测量与分析。结果表明,Na... 近年来凝聚态物理领域中,学者逐渐利用更加先进的技术,如核磁共振技术对不同材料进行更加详细的研究。因此研究利用凝聚态核磁共振技术对新型NaKV_(4)O_(9)·2H_(2)O材料与多铁性材料CuBr_(2)的物理性质进行测量与分析。结果表明,NaKV_(4)O_(9)·2H_(2)O曲线的峰部位置随着温度的不断增长,且在温度到120K附近的时候偏移量达到最大。CuBr_(2)的相变温度从72K升高到117.5K。综上所述,通过凝聚态核磁共振技术能更准确地察觉不同材料的物性变化规律。 展开更多
关键词 凝聚态物理 核磁共振 NaKV_(4)O_(9)·2H_(2)O 多铁性材料
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Poly I:C刺激对杜洛克×二花脸F2猪血液参数的影响
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作者 王海燕 贺佳玮 +4 位作者 向安静 章程 朱猛进 赵书红 刘向东 《华中农业大学学报》 CAS CSCD 北大核心 2016年第4期76-81,共6页
为研究聚肌胞苷酸(polyinosinic:polycytidylic acid,简称Poly I:C)刺激对杜洛克×二花脸F2猪群血液参数的影响,选用杜洛克×二花脸F2猪393头,在33d时前腔静脉采血(对照组),在35d时用Poly(I:C)刺激,4h后采血(处理组),对刺激前... 为研究聚肌胞苷酸(polyinosinic:polycytidylic acid,简称Poly I:C)刺激对杜洛克×二花脸F2猪群血液参数的影响,选用杜洛克×二花脸F2猪393头,在33d时前腔静脉采血(对照组),在35d时用Poly(I:C)刺激,4h后采血(处理组),对刺激前后血液参数进行相关性和主成分等分析。研究结果表明,处理组与对照组相比,白细胞中的嗜中性粒细胞百分比(NE%)、淋巴细胞数(LY)和淋巴细胞百分比(LY%)这3项血液参数差异显著相关,红细胞中的红细胞压积(HCT%)和红细胞数(RBC)差异相关性显著,而血小板第一主成分中决定性指标血小板数(PLT)和血小板压积(PCT)在刺激前后不存在显著差异。 展开更多
关键词 F2群体 poly I:C 血液参数 相关性分析 主成分分析
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Preparation and shape memory properties of TiO_2/PLCL biodegradable polymer nanocomposites 被引量:3
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作者 鲁玺丽 吕秀乾 +2 位作者 王建永 孙志洁 佟运祥 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期120-127,共8页
The preparation of TiO2/poly(L-lactide-co-ε-caprolactone)(PLCL) nanocomposites and their properties were reported.TiO2nanoparticles were surface modified by ring-opening polymerization of ε-caprolactone(ε-CL)... The preparation of TiO2/poly(L-lactide-co-ε-caprolactone)(PLCL) nanocomposites and their properties were reported.TiO2nanoparticles were surface modified by ring-opening polymerization of ε-caprolactone(ε-CL).The resulting poly(ε-caprolactone)-grafted TiO2(g-TiO2) was characterized by Fourier transform infrared spectroscopy(FTIR),thermogravimetric analysis(TGA) and transmission electron microscopy(TEM).The g-TiO2can be uniformly dispersed in chloroform and the g-TiO2/PLCL nanocomposites were successfully fabricated through solvent-casting method.The effects of the content of g-TiO2nanoparticles on tensile properties and shape memory properties were investigated.A significant improvement in the tensile properties of the 5% g-TiO2/PLCL mass fraction nanocomposite is obtained:an increase of 113% in the tensile strength and an increase of 11% in the elongation at break over pure PLCL polymer.The g-TiO2/PLCL nanocomposites with a certain amount of g-TiO2content have better shape memory properties than pure PLCL polymer.The g-TiO2nanoparticles play an additional physical crosslinks which are contributed to improvement of the shape memory properties. 展开更多
关键词 poly(L-lactide-co-ε-caprolactone) NANOCOMPOSITES TiO2nanoparticles surface grafting shape memory properties mechanical properties
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Kinetic hydrate inhibitor performance of new copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s with TBAB 被引量:8
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作者 Jun Hu Sijia Li +3 位作者 Yanhong Wang Xuemei Lang Qingping Li Shuanshi Fan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第2期126-131,共6页
In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the c... In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the combined use of KHIs and some synergists, which would enhance KHIs’ inhibitory effect on both hydrate nucleation and hydrate crystal growth. In this study, a novel kind of KHI copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s (HGs) is used in conjunction with TBAB to show its high performance on hydrate inhibition. The performance of HGs with different monomer ratios in structure II tetrahydrofuran (THF) hydrate is investigated using kinetic hydrate inhibitor evaluation apparatus by step-cooling method and isothermal cooling method. With the combined gas hydrate inhibitor at the concentration of 1.0 wt%, the induction time of 19 wt% THF solution could be prolonged to 8.5 h at a high subcooling of 6℃. Finally, the mechanism of HGs inhibiting the formation of gas hydrate is proposed. 展开更多
关键词 clathrate hydrate kinetic hydrate inhibitors combined hydrate inhibitors poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)
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Anticorrosion Coatings from Poly(Aniline-co-2-Ethylaniline) Micro/Nanostructures 被引量:2
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作者 XING Cuijuan SONG Xinling +2 位作者 ZHANG Zhiming JIANG Xiaohui YU Liangmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1371-1381,共11页
PANI copolymer micro/nanostructures with different surface wettability were obtained from the chemical oxidation copolymerization of aniline(Ani)with 2-ethyl aniline(EA)at diverse[EA]/[Ani+EA]molar ratios,by employing... PANI copolymer micro/nanostructures with different surface wettability were obtained from the chemical oxidation copolymerization of aniline(Ani)with 2-ethyl aniline(EA)at diverse[EA]/[Ani+EA]molar ratios,by employing ammonium persulfate as an oxidant.The results revealed that the poly(aniline-co-2-ethyl aniline)(PANI-EA)copolymer micro/nanostructures exhibited satisfactory anticorrosion performance for carbon steel,and the corrosion protection efficiency increased with the increase of water repellent property.Poly(2-ethyl aniline)(PEA)showed the largest contact angle(CA=145°)and show the best corrosion protection for the carbon steel(h=87.29%).It is found that the superior anticorrosion property of PEA is attributed to its high hydrophobicity,low conductivity and low porosity. 展开更多
关键词 polyANILINE poly(aniline-co-2-ethylaniline)micro/nanostructures CORROSION PROTECTION WETTABILITY
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Synthesis of Comblike Poly(methyl methacrylate) by Atom Transfer Radical Polymerization with Poly(ethyl 2-bromoacrylate) as Macroinitiator 被引量:2
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作者 YanSHI ZhiFengFU +1 位作者 YuDongZHANG ShuKeJIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1289-1292,共4页
Comblike poly(methyl methacrylate) was synthesized by atom transfer radical polymerization of methyl methacrylate with poly(ethyl 2-bromoacrylate) as a macroinitiator, which was prepared by conventional free radical p... Comblike poly(methyl methacrylate) was synthesized by atom transfer radical polymerization of methyl methacrylate with poly(ethyl 2-bromoacrylate) as a macroinitiator, which was prepared by conventional free radical polymerization of ethyl 2-bromoacrylate. The obtained comblike polymers were characterized by GPC and 1H NMR. 展开更多
关键词 Comblike polymer atom transfer radical polymerization (ATRP) MACROINITIATOR poly(methyl methacrylate) ethyl 2-bromoacrylate.
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One-pot Synthesis of 2,5-Disubstituted Oxazoles Using Poly[styrene(iodosodiacetate)] 被引量:1
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作者 JiangMinCHEN LuLingWU XianHUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第2期143-144,共2页
Disubstituted oxazoles were prepared conveniently by treatment of aromatic -methyl ketones and nitriles with poly[styrene(iodosodiacetate)] in one-pot process.
关键词 poly[styrene(iodosodiacetate)] one-pot synthesis 2 5-disubstituted oxazoles.
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Preparation and phase change performance of Na_2HPO_4·12H_2O@poly(lactic acid) capsules for thermal energy storage 被引量:4
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作者 Na Fan Lang Chen +3 位作者 Guoyong Xie Donghong Yin Chak-Tong Au Shuangfeng Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第3期695-700,共6页
Micro-encapsulated phase-change materials(micro PCMs) with Na_2 HPO_4·12 H_2 O encapsulated in poly(lactic acid)(PLA) shell were prepared by a solvent evaporation–precipitation method that involves the use of a ... Micro-encapsulated phase-change materials(micro PCMs) with Na_2 HPO_4·12 H_2 O encapsulated in poly(lactic acid)(PLA) shell were prepared by a solvent evaporation–precipitation method that involves the use of a coaxial needle. The effects of PLA concentration, stirring speed, injection rate of core and shell solutions, and polyvinyl alcohol(PVA) concentration on phase change properties were investigated. The thermal properties of microP CMs were characterized by differential scanning calorimetry(DSC). The capsules prepared under the optimal conditions are about 2 mm in diameter and show a latent heat of up to 122.2 J·g^(-1). 展开更多
关键词 Micro-encapsulated PHASE-CHANGE materials Na2HPO4·12H2O Coaxial needle poly(lactic acid) Thermal energy storage CAPSULE
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