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粒径与表面电荷影响脂质体体内药物靶向递送的研究进展 被引量:35
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作者 杨艳芳 谢向阳 +2 位作者 杨阳 张慧 梅兴国 《药学学报》 CAS CSCD 北大核心 2013年第11期1644-1650,共7页
脂质体进入体内血液循环,通过被动靶向作用聚集于网状内皮系统(reticuloendothelial system,RES)比较丰富的器官。靶向性是脂质体作为药物载体的一个重要特征,粒径和表面电荷是影响脂质体在体内被动靶向的重要理化因素。本文阐述了脂质... 脂质体进入体内血液循环,通过被动靶向作用聚集于网状内皮系统(reticuloendothelial system,RES)比较丰富的器官。靶向性是脂质体作为药物载体的一个重要特征,粒径和表面电荷是影响脂质体在体内被动靶向的重要理化因素。本文阐述了脂质体的粒径和表面电荷对其与细胞结合和被细胞摄取的影响,并从体内组织器官的生理特点出发,介绍了粒径和表面电荷对脂质体在血液、肝、脾及肿瘤组织分布的影响。对今后的研究方向进行了展望。 展开更多
关键词 脂质体 粒径 表面电荷 药物递送 体内靶向
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Dual-responsive nanoparticles with transformable shape and reversible charge for amplified chemo-photodynamic therapy of breast cancer 被引量:6
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作者 Wenfeng Jia Rui Liu +7 位作者 Yushan Wang Chuan Hu Wenqi Yu Yang Zhou Ling Wang Mengjiao Zhang Huile Gao Xiang Gao 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第8期3354-3366,共13页
Herein, we designed a dual-response shape transformation and charge reversal strategy with chemo-photodynamic therapy to improve the blood circulation time, tumor penetration and retention,which finally enhanced the a... Herein, we designed a dual-response shape transformation and charge reversal strategy with chemo-photodynamic therapy to improve the blood circulation time, tumor penetration and retention,which finally enhanced the anti-tumor effect. In the system, hydrophobic photosensitizer chlorin e6(Ce6), hydrophilic chemotherapeutic drug berberrubine(BBR) and matrix metalloproteinase-2(MMP-2) response peptide(PLGVRKLVFF) were coupled by linkers to form a linear triblock molecule BBR-PLGVRKLVFF-Ce6(BPC), which can self-assemble into nanoparticles. Then, positively charged BPC and polyethylene glycol-histidine(PEG-His) were mixed to form PEG-His@BPC with negative surface charge and long blood circulation time. Due to the acidic tumor microenvironment, the PEG shell was detached from PEG-His@BPC attributing to protonation of the histidine, which achieved charge reversal, size reduction and enhanced tumor penetration. At the same time, enzyme cutting site was exposed, and the spherical nanoparticles could transform into nanofibers following the enzymolysis by MMP-2, while BBR was released to kill tumors by inducing apoptosis. Compared with original nanoparticles, the nanofibers with photosensitizer Ce6 retained within tumor site for a longer time. Collectively,we provided a good example to fully use the intrinsic properties of different drugs and linkers to construct tumor microenvironment-responsive charge reversal and shape transformable nanoparticles with synergistic antitumor effect. 展开更多
关键词 Shape transformation charge reversal Chemo-photodynamic therapy Self-delivery MMP-2 response p H response Carrier-free nanoparticles Breast cancer
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Integrated prodrug micelles with two-photon bioimaging and pH-triggered drug delivery for cancer theranostics 被引量:4
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作者 Hong Xu Boxuan Ma +5 位作者 Jizhou Jiang Sutong Xiao Rongrong Peng Weihua Zhuang Gaocan Li Yunbing Wang 《Regenerative Biomaterials》 SCIE EI 2020年第2期171-180,共10页
Nanodrug carriers with fluorescence radiation are widely used in cancer diagnosis and therapy due to their real-time imaging,less side effect,better drug utilization as well as the good bioimaging ability.However,trad... Nanodrug carriers with fluorescence radiation are widely used in cancer diagnosis and therapy due to their real-time imaging,less side effect,better drug utilization as well as the good bioimaging ability.However,traditional nanocarriers still suffer from unexpectable drug leakage,unsatisfactory tumor-targeted drug delivery and shallow imaging depth,which limit their further application in cancer theranostics.In this study,an integrated nanoplatform is constructed by polymeric prodrug micelles with two-photon and aggregation-induced emission bioimaging,charge reversal and drug delivery triggered by acidic pH.The prodrug micelles can be self-assembled by the TPPEI(DA/DOX)-PEG prodrug polymer,which consists of the two-photon fluorophore(TP),dimethylmaleic anhydride(DA)grafted polyethyleneimine(PEI)and polyethylene glycol(PEG).The PEG segment,DOX and DA are bridged to polymer by acid cleavable bonds,which provides the micelles a‘stealth’property and a satisfactory stability during blood circulation,while the outside PEG segment is abandoned along with the DA protection in the tumor acidic microenvironment,thus leading to charge reversal-mediated accelerated endocytosis and tumor-targeted drug delivery.The great antitumor efficacy and reduced side effect of these pH-sensitive prodrug micelles are confirmed by antitumor assays in vitro and in vivo.Meanwhile,these micelles exhibited great deep-tissue two-photon bioimaging ability up to 150 lm in depth.The great antitumor efficacy,reduced side effect and deep two-photon tissue imaging make the TP-PEI(DA/DOX)-PEG prodrug micelles would be an efficient strategy for theranostic nanoplatform in cancer treatment. 展开更多
关键词 aggregation-induced emission TWO-PHOTON PH-SENSITIVE charge reversal drug delivery system
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Preparation and Characterization of pH-Responsive Charge Reversal Nanocomposite for miRNA Delivery
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作者 余丹 YE Liyuan +2 位作者 LI Binbin MOU Fangzhi 殷义霞 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期1048-1052,共5页
pH-responsive charge reversal loaded miRNA nanocomposite was prepared by electrostatic self-assembly.The morphology,particle size and zeta potential of the nanocomposites were analyzed by transmission electron microsc... pH-responsive charge reversal loaded miRNA nanocomposite was prepared by electrostatic self-assembly.The morphology,particle size and zeta potential of the nanocomposites were analyzed by transmission electron microscopy and dynamic light scattering.The synthesis of the polymer was analyzed by^(1)H-NMR.The zeta-potential changes and cellular uptake effects of the nanocomplexes under different pH environments were investigated.The experimental results show that the surface morphology of the nanocomposite is spherical,and the average particle size is about 135 nm.As the pH value of the solution gradually decreases,the surface charge of the nanocomposite reverses from negative charge to positive charge(from-9.4 to+17.1 mV).Cellular uptake mediated by pH-responsive nanocomposite is selective for tumor cells,and the cellular uptake effect in tumor cells at pH 6.5 was approximately 3 times higher than that at pH 7.4.This pH responsive charge reversal nanocomposite has promising application prospects for gene delivery in the weak acid environment of tumors. 展开更多
关键词 charge conversion siRNA delivery pH responsive cancer therapy
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Surface charge tunable nanoparticles for TNF-α siRNA oral delivery for treating ulcerative colitis 被引量:2
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作者 Shoaib Iqbal Xiaojiao Du +3 位作者 Jilong Wang Hongjun Li Youyong Yuan Jun Wang 《Nano Research》 SCIE EI CAS CSCD 2018年第5期2872-2884,共13页
Nanopartide (NP) drug delivery systems have been successfully designed and implemented to orally deliver small interfering RNAs (siRNAs) for inflammatory disorders. However, the influence of surface charge on oral... Nanopartide (NP) drug delivery systems have been successfully designed and implemented to orally deliver small interfering RNAs (siRNAs) for inflammatory disorders. However, the influence of surface charge on orally administered siRNA nanocarriers has not been investigated. In this study, we prepared structurally related poly(ethylene glycol)-block-poly(lactic-co-glycolic acid) (PEG5K-b-PLGA10K) NPs with the assistance of a synthesized lipid featuring surface amine groups for subsequent charge tuning. NPs were prepared by a double emulsion method, and their surface charge could be tuned and controlled by a succinylation reaction to yield NPs with different surface charges, while maintaining their size and composition. The prepared NPs were termed as aminated NPs (ANPs), plain NPs (PNPs), or carboxylated NPs (CNPs) based on their surface charge. All NPs exhibited the desired structural stability and siRNA integrity after enzymatic degradation. In vivo studies showed that ANPs significantly accumulated in inflamed colons, and they were successful in decreasing TNF-α secretion and mRNA expression levels while maintaining colonic histology in a murine model of acute ulcerative colitis (UC). This study described a methodology to modify the surface charge of siRNA-encapsulating polymeric NPs and highlighted the influence of surface charge on oral delivery of siRNA for localized inflammatory disorders. 展开更多
关键词 surface charge tumor necrosis factor alpha(TNF-α) small interferingRNA (siRNA) drug delivery polymeric nanoparticles ulcerative colitis
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Positively charged graphene/Fe3O4/polyethylenimine with enhanced drug loading and cellular uptake for magnetic resonance imaging and magnet-responsive cancer therapy 被引量:2
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作者 Baoji Du Jianhua Liu +4 位作者 Guanyu Ding Xu Han Dan Li ErkangWang Jin Wang 《Nano Research》 SCIE EI CAS CSCD 2017年第7期2280-2295,共16页
Enhanced cellular uptake efficiency of nanoparticles is important for their biomedical applications, including photothermal therapy (PTT) for cancer. In this study, a one-pot method was used to construct a positivel... Enhanced cellular uptake efficiency of nanoparticles is important for their biomedical applications, including photothermal therapy (PTT) for cancer. In this study, a one-pot method was used to construct a positively charged and magnet-responsive nanocomposite comprising reduced graphene oxide anchoring iron oxide (RGI) with a polyethylenimine (PEI) modification, to improve the efficiency of cell internalization. The surface charge can be finely tuned using PEIs of different molecular weights. The obtained RGIlsk composite (RGI modified by 1.8 kDa PEI) could load indocyanine green (ICG) at a high mass ratio of 10:3 and ablate cancer cells using low-density laser irradiation because of its positively charged surface. In addition, the hybrids of RGI1.8k and ICG could kill most cancer cells at a laser density of 0.7 W/cm2 in vitro and 0.3 W/cm2 in vivo. At the same time, cell viability could be controlled by converting the external magnetic-field direction because of the enrichment of the magnet-responsive composite in vitro and in vivo. Furthermore, RGIr8k-ICGs could be used as T2-weighted magnetic resonance and infrared thermal imaging agents. Coupled with the magnetic target effect, the imaging signal could be improved significantly. Therefore, RGII^sk-ICGs represent a new highly efficient PTT and imaging agent with great potential for cancer treatment. 展开更多
关键词 surface charge low laser density synergistic therapy magnetic resonanceimaging photothermal therapy drug delivery
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活性氧响应的新型阳离子共聚物构建及其基因递送性能研究 被引量:3
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作者 韩旭 张留伟 +4 位作者 张强 睢晞航 钱明 陈麒先 王静云 《化学学报》 SCIE CAS CSCD 北大核心 2021年第6期794-802,共9页
引入快速、主动释放基因的机制是提升非病毒基因递送效率的关键.本研究以2-甲基丙烯酰氧乙基磷酰胆碱(MPC)与(2-丙烯酰基)乙基(硼酸苄基)二乙基溴化铵(BD)为单体,基于可逆加成-断裂链转移聚合(RAFT)反应制备具有活性氧响应性质的聚阳离... 引入快速、主动释放基因的机制是提升非病毒基因递送效率的关键.本研究以2-甲基丙烯酰氧乙基磷酰胆碱(MPC)与(2-丙烯酰基)乙基(硼酸苄基)二乙基溴化铵(BD)为单体,基于可逆加成-断裂链转移聚合(RAFT)反应制备具有活性氧响应性质的聚阳离子嵌段共聚物pM-pBD.通过静电作用,阳离子共聚物pM-pBD能够与带负电荷的DNA以分子自组装的方式形成纳米复合物.其中,阳离子pBD片段具有活性氧触发电荷反转的特性,因此,有助于获得活性氧触发的静电组装复合体结构解离,从而实现可控基因释放的功能.理化表征结果表明,pM-pBD与质粒DNA静电复合后能够形成粒径约为99.1 nm,ζ电位约为+13.8 mV,显微形貌近似球形的纳米复合物.在加入促过氧化氢产生的抗坏血酸后,上述pM-pBD基因递送系统的转染效率得到了显著的提升.因此,本研究创制的pM-pBD为基因递送系统的可控释放提供了新的解决方案. 展开更多
关键词 聚阳离子 电荷反转 基因递送 活性氧响应 抗坏血酸
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Dendrimer-decorated nanogels:Efficient nanocarriers for biodistribution in vivo and chemotherapy of ovarian carcinoma 被引量:3
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作者 Xin Li Zhijun Ouyang +5 位作者 Helin Li Chaolei Hu Pabitra Saha Lingxi Xing Xiangyang Shi Andrij Pich 《Bioactive Materials》 SCIE 2021年第10期3244-3253,共10页
Nanomedicine has revolutionized disease theranostics by the accurate diagnosis and efficient therapy.Here,the PAMAM dendrimer decorated PVCL-GMA nanogels(NGs)were developed for favorable biodistribution in vivo and en... Nanomedicine has revolutionized disease theranostics by the accurate diagnosis and efficient therapy.Here,the PAMAM dendrimer decorated PVCL-GMA nanogels(NGs)were developed for favorable biodistribution in vivo and enhanced antitumor efficacy of ovarian carcinoma.By an ingenious design,the NGs with a unique structure that GMA-rich domains were localized on the surface were synthesized via precipitation polymerization.After G2 dendrimer decoration,the overall charge is changed from neutral to positive,and the NGs-G2 display the whole charge nature of positively charged corona and neutral core.Importantly,the unique architecture and charge conversion of NGs-G2 have a profound impact on the biodistribution and drug delivery in vivo.As a consequence of this alteration,the NGs-G2 as nanocarriers emerge the highly sought biodistribution of reduced liver accumulation,enhanced tumor uptake,and promoted drug release,resulting in the significantly augmented antitumor efficacy with low side effects.Remarkably,this finding is contrary to some reported work that the nanocarriers with positive charge have preferential liver uptake.Moreover,the NGs-G2 also displayed thermal/pH dual-responsive behaviors,excellent biocompatibility,improved cellular uptake,and stimuli-responsive drug release.Encouragingly,this work demonstrates a novel insight into the strategy for optimizing design,improving biodistribution and enhancing theranostic efficacy of nanocarriers. 展开更多
关键词 NANOGELS DENDRIMER Surface charge Thermal/pH dual-responsiveness Drug delivery
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Charge-reversible crosslinked nanoparticle for pro-apoptotic peptide delivery and synergistic photodynamic cancer therapy 被引量:2
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作者 Haijing Qu Han Chen +5 位作者 Wei Cheng Yuqing Pan Zhiran Duan Yanjun Wang Xing-Jie Liang Xiangdong Xue 《Nano Research》 SCIE EI CSCD 2023年第12期13267-13282,共16页
Although anti-cancer nanotherapeutics have made breakthroughs,many remain clinically unsatisfactory due to limited delivery efficiency and complicated biological barriers.Here,we prepared charge-reversible crosslinked... Although anti-cancer nanotherapeutics have made breakthroughs,many remain clinically unsatisfactory due to limited delivery efficiency and complicated biological barriers.Here,we prepared charge-reversible crosslinked nanoparticles(PDC NPs)by supramolecular self-assembly of pro-apoptotic peptides and photosensitizers,followed by crosslinking the self-assemblies with polyethylene glycol to impart tumor microenvironment responsiveness and charge-reversibility.The resultant PDC NPs have a high drug loading of 68.3%,substantially exceeding that of 10%–15%in conventional drug delivery systems.PDC NPs can overcome the delivery hurdles to significantly improve the tumor accumulation and endocytosis of payloads by surface charge reversal and responsive crosslinking strategy.Pro-apoptotic peptides target the mitochondrial membranes and block the respiratory effect to reduce local oxygen consumption,which extensively augments oxygen-dependent photodynamic therapy(PDT).The photosensitizers around mitochondria increased along with the peptides,allowing PDT to work with pro-apoptotic peptides synergistically to induce tumor cell death by mitochondria-dependent apoptotic pathways.Our strategy would provide a valuable reference for improving the delivery efficiency of hydrophilic peptides and developing mitochondrial-targeting cancer therapies. 展开更多
关键词 charge-reversible nanoparticle crosslinked nanoparticle peptide delivery photodynamic therapy synergistic cancer treatment
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投弹初始条件对弹伞系统入水参数的影响与分析 被引量:2
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作者 程善政 李宗吉 王树宗 《弹箭与制导学报》 CSCD 北大核心 2012年第1期157-161,共5页
为分析投放条件对入水参数的影响,建立了弹伞系统纵平面内的弹道数学模型,利用Matlab/Simu-link软件对入水参数随投弹参数的变化进行了仿真,并针对满足正态分布的投弹参数对入水参数的散布影响做了进一步的分析,结果表明:投放高度在较... 为分析投放条件对入水参数的影响,建立了弹伞系统纵平面内的弹道数学模型,利用Matlab/Simu-link软件对入水参数随投弹参数的变化进行了仿真,并针对满足正态分布的投弹参数对入水参数的散布影响做了进一步的分析,结果表明:投放高度在较低高度时对入水参数的影响较为明显,而投放速度对物体偏离投放点的距离影响较大,投弹姿态角对入水参数的影响甚微。 展开更多
关键词 深弹 降落伞 投弹参数 入水参数
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电荷翻转型药物载体用于肿瘤细胞核靶向药物输送的研究 被引量:2
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作者 汪星平 唐建斌 +2 位作者 隋梅花 王新平 申有青 《高分子通报》 CAS CSCD 北大核心 2010年第12期22-29,共8页
大多数的抗癌药物属于DNA毒化物,它们只有作用于细胞核中的DNA或与之相关的酶才能发挥药效。但是,癌细胞先天和后天获得的耐药机制能够有效地限制抗癌药物进入细胞核。目前研制的大多数药物载体只靶向细胞中的溶酶体、不能进入细胞核。... 大多数的抗癌药物属于DNA毒化物,它们只有作用于细胞核中的DNA或与之相关的酶才能发挥药效。但是,癌细胞先天和后天获得的耐药机制能够有效地限制抗癌药物进入细胞核。目前研制的大多数药物载体只靶向细胞中的溶酶体、不能进入细胞核。最近,β-羧基酰胺化的阳离子聚合物如聚乙烯亚胺(PEI)和聚L-赖氨酸(PLL)被发展为从负电向正电翻转的新型细胞核靶向的药物载体,用于将药物直接输送到癌细胞的细胞核中,从而使药物避开肿瘤细胞膜及细胞浆中的多种耐药机制。在生理环境中,β-羧基酰胺化的阳离子聚合物带负电荷,抑制了阳离子聚合物与血液中蛋白质及细胞之间的非特异性相互作用。而当载体被癌细胞内吞并进入其酸性的溶酶体后,β-羧基酰胺键很快水解为胺基,载体又变为带正电荷,使载体能够逃离溶酶体并进入细胞核,将药物释放到细胞核中。实验结果表明,肿瘤靶向电荷翻转型药物载体能够有效地将药物输送到细胞核中,从而使药物避开癌细胞的耐药机制,提高药物疗效。本文就电荷翻转药物载体的进展做了简述。 展开更多
关键词 肿瘤靶向药物输送 细胞核靶向 电荷翻转 药物载体
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电子倍增CCD中电荷载流子倍增寄存器的分布式等效电路模型 被引量:2
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作者 周蓓蓓 陈钱 何伟基 《红外与激光工程》 EI CSCD 北大核心 2011年第2期229-234,共6页
为了研究电子倍增电荷耦合器件(EMCCD)中电荷载流子倍增寄存器(CCM)内部电荷的倍增及转移特性,提出了一种适用于CCM的电荷传输机制仿真的分布式等效电路模型。利用泊松方程求解了均匀掺杂条件下CCM单元的电势分布,通过基尔霍夫电压定律(... 为了研究电子倍增电荷耦合器件(EMCCD)中电荷载流子倍增寄存器(CCM)内部电荷的倍增及转移特性,提出了一种适用于CCM的电荷传输机制仿真的分布式等效电路模型。利用泊松方程求解了均匀掺杂条件下CCM单元的电势分布,通过基尔霍夫电压定律(KVL)得到了该单元的最大电势表达式,从而得到了其分布式等效电路。同时,结合该单元内的电势分布求解,最终得到了分布式等效电路模型。通过对该模型的分析表明:CCM单元内电极间的间隙越小,电荷倍增率越大。CCM电荷传输主要受到自感生电场和热扩散电场作用,由于自感生电场的电荷迁移率作用,大部分电荷在时钟周期的初始阶段完成转移。 展开更多
关键词 电荷载流子倍增寄存器 电子倍增电荷耦合器件 电荷传输 等效电路
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A microenvironment sensitive pillar[5]arene-based fluorescent probe for cell imaging and drug delivery 被引量:1
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作者 Qing Wang Jingwen Fan +4 位作者 Xiaoyan Bian Hang Yao Xiaohui Yuan Ying Han Chaoguo Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第4期1979-1982,共4页
Dansylamide(DNSA) is a typical ICT probe that has a favorable serum albumin sensitivity. Inspired by this, we designed a microenvironment sensitive fluorescent probe 4 C-G through introducing DNSA into pillar[5]arene.... Dansylamide(DNSA) is a typical ICT probe that has a favorable serum albumin sensitivity. Inspired by this, we designed a microenvironment sensitive fluorescent probe 4 C-G through introducing DNSA into pillar[5]arene. Unlike DNSA, 4 C-G displayed differentiated sensitivity to multiple proteins, which was benefit from pillar[5]arene assisted the probe to form complexes with proteins. 4 C-G could not only be applied in imaging of Hep G2, but also act as a favorable drug carrier for regorafenib(REG) encapsulation.The 4 C-G-REG complex would aggregate into high drug-loading fluorescent nanoparticles in a physiological environment(pH 7.4). Such nanoparticles exhibited p H-triggered enrichment ability, which rapidly enriched REG in the acidic environment(pH 6.0). Furthermore, the complexation between 4 C-G and REG maintained the imaging property of the probe and the excellent anticancer activity of the drug on Hep G2. 展开更多
关键词 Fluorescent probe Intramolecular charge transfer arene Cell imaging Drug delivery
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刺激响应型电荷翻转纳米材料在药物递送中的应用 被引量:1
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作者 杨锐 刘永军 张娜 《药物生物技术》 CAS 2019年第4期343-347,共5页
电荷翻转材料作为一种刺激响应型材料,可利用人体正常生理组织、肿瘤微环境及亚细胞器环境之间的差异,实现电荷翻转。利用这种材料制备的电荷翻转型纳米载体可在肿瘤部位实现表面电荷、粒径等理化性质的响应性改变,从而达到增加药物的... 电荷翻转材料作为一种刺激响应型材料,可利用人体正常生理组织、肿瘤微环境及亚细胞器环境之间的差异,实现电荷翻转。利用这种材料制备的电荷翻转型纳米载体可在肿瘤部位实现表面电荷、粒径等理化性质的响应性改变,从而达到增加药物的递送靶向性与蓄积能力、降低毒副作用、促进入胞等目的。基于以上优势,电荷翻转型材料成为目前药物递送研究的热点。因此,该文根据不同翻转机制对电荷翻转材料进行分类,并归纳了其在药物递送中的应用,以期为新型纳米药物载体的研究提供新的思路和方法。 展开更多
关键词 电荷翻转 刺激响应 肿瘤微环境 纳米材料 药物递送 肿瘤治疗
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载血卟啉单甲醚电荷反转型纳米载体构建及评价
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作者 徐爱仁 戎建辉 +4 位作者 陈梦嘉 冯政红 马卫成 沈松 金一 《药学学报》 CAS CSCD 北大核心 2017年第10期1605-1610,共6页
构建具有电荷反转功能的纳米载体,实现药物的溶酶体逃逸,提高抗肿瘤效果。合成胆固醇-聚乙烯亚胺-六氢邻苯二甲酸酐(Chol-PEI-HHPA)聚合物,利用1H NMR进行结构表征,构建具有电荷反转功能的脂质体(Lipo-HHPA)并负载声敏药物血卟啉单甲醚(... 构建具有电荷反转功能的纳米载体,实现药物的溶酶体逃逸,提高抗肿瘤效果。合成胆固醇-聚乙烯亚胺-六氢邻苯二甲酸酐(Chol-PEI-HHPA)聚合物,利用1H NMR进行结构表征,构建具有电荷反转功能的脂质体(Lipo-HHPA)并负载声敏药物血卟啉单甲醚(HMME),考察Lipo-HHPA-HMME在不同p H条件下的电荷反转情况,利用MCF-7细胞研究载体的溶酶体逃逸及细胞毒性。结果显示,所构建的Lipo-HHPA外观均匀,平均粒径为102 nm,在超声激发下可实现HMME的突释;当pH从7.4变为4.5时,其表面电位由-23.5 mV反转为+21.2 mV;体外细胞实验结果显示,Lipo-HHPA可逃逸溶酶体降解,提高HMME的细胞毒性。以上结果表明,电荷反转型载体有利于增强药物的细胞毒性,提高抗肿瘤效果。 展开更多
关键词 电荷反转 溶酶体逃逸 血卟啉单甲醚 声动力治疗 靶向递送
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防静电服带电电荷量测试方法的探讨
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作者 任春祥 《石油工业技术监督》 2022年第11期18-21,共4页
针对GB 12014—2019《防护服装防静电服》中带电电荷量测试方法重复性、再现性差的问题,在人体静电产生机理及带电电荷量检测原理的基础上设计比对实验。对方法中影响检测结果的投放方式、滚筒转速及环境因素进行分析比对,发现投放方式... 针对GB 12014—2019《防护服装防静电服》中带电电荷量测试方法重复性、再现性差的问题,在人体静电产生机理及带电电荷量检测原理的基础上设计比对实验。对方法中影响检测结果的投放方式、滚筒转速及环境因素进行分析比对,发现投放方式的选择、滚筒转速的设置及环境因素均对检测结果影响较大。研究表明:GB 12014—2019标准中应限定样品的投放方式为自动投放,并规定滚筒摩擦机滚筒转速上限。通过分析结果,提出了检验检测机构在进行带电电荷量检测时的注意事项,并对防静电服使用管理过程中的环境要求、穿着使用、产品选用方面提出若干建议。 展开更多
关键词 防静电服 带电电荷量 检验检测 投放方式 滚筒转速
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三门峡水库汛期排沙效果研究 被引量:17
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作者 侯素珍 胡恬 +1 位作者 杨飞 王平 《水利学报》 EI CSCD 北大核心 2021年第4期393-400,共8页
三门峡水库汛期排沙是解决泥沙淤积问题、控制潼关高程的关键途径。“蓄清排浑”运用以来,非汛期蓄水期库区发生淤积、汛期降低水位运用排泄全年泥沙,基本保持了库区动态冲淤平衡。不同控制水位和入库流量过程存在不同的排沙效果,针对... 三门峡水库汛期排沙是解决泥沙淤积问题、控制潼关高程的关键途径。“蓄清排浑”运用以来,非汛期蓄水期库区发生淤积、汛期降低水位运用排泄全年泥沙,基本保持了库区动态冲淤平衡。不同控制水位和入库流量过程存在不同的排沙效果,针对三门峡水库汛期排沙过程的差异,对“蓄清排浑”运用以来汛期排沙特征进行统计,分析了水库敞泄和不同控制水位运用对排沙效果的影响。结果表明,在汛期平水305 m、洪水敞泄的运用条件下,水库排沙具有多来多排的特点,汛期排沙总量与入库含沙量和水量密切相关;完全敞泄时库区冲刷取决于流量大小和敞泄时间,净排沙效率随着水量的增加和敞泄时间的延长而减小,冲刷效率降低;汛期控制运用期,当流量在1000 m³/s以上时、水位在305~311 m也会产生一定的排沙,排沙效果取决于含沙水流在壅水段的滞留时间和出入库流量之比。研究成果可为三门峡水库运用方式的优化提供依据。 展开更多
关键词 三门峡水库 运用水位 净排沙量 敞泄排沙 排沙比
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Charge-reversal nanoparticles: novel targeted drug delivery carriers 被引量:10
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作者 Xinli Chen Lisha Liu Chen Jiang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2016年第4期261-267,共7页
Spurred by significant progress in materials chemistry and drug delivery, charge-reversal nanocarriers are being developed to deliver anticancer formulations in spatial-, temporal- and dosagecontrolled approaches. Cha... Spurred by significant progress in materials chemistry and drug delivery, charge-reversal nanocarriers are being developed to deliver anticancer formulations in spatial-, temporal- and dosagecontrolled approaches. Charge-reversal nanoparticles can release their drug payload in response to specific stimuli that alter the charge on their surface. They can elude clearance from the circulation and be activated by protonation, enzymatic cleavage, or a molecular conformational change. In this review, we discuss the physiological basis for, and recent advances in the design of charge-reversal nanoparticles that are able to control drug biodistribution in response to specific stimuli, endogenous factors(changes in p H,redox gradients, or enzyme concentration) or exogenous factors(light or thermos-stimulation). 展开更多
关键词 Cancer therapy charge-reversal NANOPARTICLES DRUG delivery carriers Stimuli RESPONSIVE NANOTECHNOLOGY
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首钢迁钢2160热轧加热炉工程设计 被引量:4
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作者 李春生 苗为人 +3 位作者 陈迪安 刘文田 余威 刘志民 《冶金能源》 北大核心 2007年第6期35-38,共4页
热轧车间炉区平面布置的合理与否直接影响生产操作以及工艺的连续性,而加热炉炉型的选择直接关系到板坯加热质量的好坏。本文重点介绍2160热轧加热炉平面布置和炉型设计,以及如何很好适应热装热送的装料制度。
关键词 热装热送 炉型 余热回收 燃料消耗 间拔控制技术
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炼钢-热轧生产计划的优化与协调 被引量:4
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作者 于港 田乃媛 +1 位作者 徐安军 贺东风 《冶金能源》 2009年第4期6-9,共4页
炼钢和热轧是钢铁企业的关键工序,它们的生产运行情况影响着整个钢铁企业的效益。随着热送热装技术的普及,现代钢铁企业不仅追求炼钢和热轧生产计划各自的优化,更对它们之间的协调提出了更高的要求。根据最优炉次计划模型和最优轧制计... 炼钢和热轧是钢铁企业的关键工序,它们的生产运行情况影响着整个钢铁企业的效益。随着热送热装技术的普及,现代钢铁企业不仅追求炼钢和热轧生产计划各自的优化,更对它们之间的协调提出了更高的要求。根据最优炉次计划模型和最优轧制计划模型建立了炉次-轧制计划的协调模型,采用禁忌搜索算法对它们进行求解,并对模型和算法进行了仿真验证。 展开更多
关键词 炉次计划 轧制计划 热送热装 协调 禁忌搜索
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