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Jae‐Min Oh Soo‐Jin Choi Go‐Eun Lee Sun‐Ho Han Jin‐Ho Choy 《Advanced functional materials》2009,19(10):1617-1624
The surface of layered double hydroxide nanoparticles, a potential drug‐delivery nanovehicle, is modified with the cancer‐cell‐specific ligand, folic acid. The surface modification is successfully accomplished through step‐by‐step coupling reactions with aminopropyltriethoxysilane and 1‐ethyl‐3‐(3‐dimethyl aminopropyl)‐carbodiimide. In order to evaluate the cancer‐cell targeting effect of folic‐acid‐grafted layered double hydroxide utilizing fluorescence‐related assay, both layered double hydroxide with and without folic acid moiety are labeled with fluorescein 5′‐isothiocyanate. The uptake of layered double hydroxide and folic acid conjugated into KB and A549 cells is visualized using fluorescence microscopy and measured by flow cytometry. Both chemical and biological assay results demonstrate that the folic acid molecules are indeed conjugated to the surface of layered double hydroxide and thus the selectivity of nanovehicles to cancer cells overexpressing folate receptors increases. In this study, it is suggested that layered double hydroxide nanoparticles can be used as drug‐delivery carriers with a targeting function due to the chemical conjugation with specific ligand. 相似文献
23.
Meng Shi Karyn Ho Armand Keating Molly S. Shoichet 《Advanced functional materials》2009,19(11):1689-1696
A polymeric nanoparticle comprised of surface furan groups is used to bind, by Diels–Alder (DA) coupling chemistry, both targeting anti‐human epidermal growth factor receptor 2 (anti‐HER2) antibodies and chemotherapeutic doxorubicin (DOX) for targeted, intracellular delivery of DOX. In this new approach for delivery, where both chemotherapeutic and targeting ligand are attached, for the first time, to the surface of the delivery vehicle, the nuclear localization of DOX in HER2‐overexpressing breast cancer SKBR‐3 cells is demonstrated, as determined by confocal laser scanning microscopy. Flow cytometric analysis shows that the conjugated DOX maintains its biological function and induces similar apoptotic progression in SKBR‐3 cells as free DOX. The viable cell counts of SKBR‐3 cancer cells following incubation with different nanoparticle formulations demonstrates that the combined DOX and anti‐HER2 nanoparticle is more efficacious than the nanoparticle formulation with either DOX or anti‐HER2 alone. While free DOX shows similar cytotoxicity against both cancerous SKBR‐3 cells and healthy HMEC‐1 cells, the combined DOX‐anti‐HER2 nanoparticle is significantly more cytotoxic against SKBR‐3 cells than HMEC‐1 cells, suggesting the benefit of nanoparticle‐conjugated DOX for cell type‐specific targeting. The DOX‐conjugated immuno‐nanoparticle represents an entirely new method for localized co‐delivery of chemotherapeutics and antibodies. 相似文献
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Dmitry V. Volodkin Stephan Schmidt Paulo Fernandes Natalia I. Larionova Gleb B. Sukhorukov Claus Duschl Helmuth Möhwald Regine von Klitzing 《Advanced functional materials》2012,22(9):1914-1922
Formulation of therapeutic proteins into particulate forms is a main strategy for site‐specific and prolonged protein delivery as well as for protection against degradation. Precise control over protein particle size, dispersity, purity, as well as mild preparation conditions and minimal processing steps are highly desirable. It is, however, hard to fit all these criteria with conventional preparation techniques. Here a one‐step hard‐templating synthesis of microparticles composed of functional, non‐denatured protein is reported. The method is based on filling porous CaCO3 microtemplates with the protein near to its isoelectric point (pI) followed by pH‐ or EDTA‐mediated dissolution of the tempplates. In principle, a wide variety of proteins can be converted into microparticles using this approach. The main requirement is an overlap of the protein insolubility and a template solubility for a certain parameter (here pH or EDTA). Here the formulation of insulin particles is studied in detail and it is shown that particles consisting of high molecular weight protein (catalase) can also be prepared. In this context, the synthesis of CaCO3 templates with controlled size, the mechanism of the protein microparticle formation and mechanical properties of the microparticles are discussed. For the first time, the fabrication of mesoporous monodispersed CaCO3 microtemplates with identical porocity but tuned diameter from 3 to 20 μm is demonstrated. The protein particle diameter can be adjusted by choosing the appropriate template size that is critical for successful pulmonary delivery of insulin. As a first step towards insulin delivery, the in vitro release of insulin at physiological conditions is studied. 相似文献
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A Charge Reversible Self‐Delivery Chimeric Peptide with Cell Membrane‐Targeting Properties for Enhanced Photodynamic Therapy 下载免费PDF全文
Li‐Han Liu Wen‐Xiu Qiu Yao‐Hui Zhang Bin Li Chi Zhang Fan Gao Lu Zhang Xian‐Zheng Zhang 《Advanced functional materials》2017,27(25)
The cell membrane is the most important protective barrier in living cells and cell membrane targeted therapy may be a high‐performance therapeutic modality for tumor treatment. Here, a novel charge reversible self‐delivery chimeric peptide C16–PRP–DMA is developed for long‐term cell membrane targeted photodynamic therapy (PDT). The self‐assembled C16–PRP–DMA nanoparticles can effectively target to tumor by enhanced permeability and retention effect without additional carriers. After undergoing charge reverse in acidic tumor microenvironment, C16–PRP–DMA inserts into the tumor cell membrane with a long retention time of more than 14 h, which is very helpful for in vivo applications. It is found that under light irradiation, the reactive oxygen species generated by the inserted C16–PRP–DMA would directly disrupt cell membrane and rapidly induce cell necrosis, which remarkably increases the PDT effect in vitro and in vivo. This novel self‐delivery chimeric peptide with a long‐term cell membrane targeting property provides a new prospect for effective PDT of cancer. 相似文献
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6‐Mercaptopurine‐Induced Fluorescence Quenching of Monolayer MoS2 Nanodots: Applications to Glutathione Sensing,Cellular Imaging,and Glutathione‐Stimulated Drug Delivery 下载免费PDF全文
Shih‐Chiang Chen Chang‐Yu Lin Tian‐Lu Cheng Wei‐Lung Tseng 《Advanced functional materials》2017,27(41)
Molybdenum disulfide (MoS2) nanodots (NDs) with sulfur vacancies have been demonstrated to be suitable to conjugate thiolated molecules. However, thiol‐induced fluorescence quenching of MoS2 NDs has been rarely explored. In this study, 6‐mercaptopurine (6‐MP) serves as an efficient quencher for the fluorescence of monolayer MoS2 (M‐MoS2) NDs. 6‐MP molecules are chemically adsorbed at the sulfur vacancy sites of the M‐MoS2 NDs. The formed complexes trigger the efficient fluorescence quenching of the M‐MoS2 NDs due to acceptor‐excited photoinduced electron transfer. The presence of glutathione (GSH) efficiently triggers the release of 6‐MP from the M‐MoS2 NDs, thereby switching on the fluorescence of the M‐MoS2 NDs. Thus, the 6‐MP‐M‐MoS2 NDs are implemented as a platform for the sensitive and selective detection of GSH in erythrocytes and live cells. Additionally, thiolated doxorubicin (DOX‐SH)‐loaded M‐MoS2 NDs (DOX‐SH/M‐MoS2 NDs) serve as GSH‐responsive nanocarriers for DOX‐SH delivery. In vitro studies reveal that the DOX‐SH/M‐MoS2 NDs exhibit efficient uptake by HeLa cells and greater cytotoxicity than free DOX‐SH and DOX. In vivo study shows that GSH is capable of triggering the release of DOX‐SH from M‐MoS2 ND‐based nanomaterials in mice. It is revealed that the DOX‐SH/M‐MoS2 NDs can be implemented for simultaneous drug delivery and fluorescence imaging. 相似文献
29.
Liqun Dai Jie Liu Xiaosheng Zhao Yuhao Li Siming Zhou Liping Yuan Diyun Shu Lili Pan Yuan-hao Liu Zhiyong Qian 《Advanced functional materials》2023,33(23):2214145
Boron neutron capture therapy (BNCT) is a promising therapy for refractory cancer based on the cytotoxic reaction of 10B (n, α) 7Li. Although two BNCT agents are clinically available, they are quickly metabolized and show modest enrichment in tumor sites, partially limiting BNCT widespread application. Consequently, novel agents that perform active targeting and show good biocompatibility have to be developed. Herein, boronophenylalanine-containing polydopamine (B-PDA) nanoparticles are easily fabricated by encapsulating boronophenylalanine (BPA) in polydopamine via nitrogen-boronate coordination. In this study, B-PDA achieves increased tumor accumulation and prolonged retention effects in the tumor site and superior antitumor activity post neutron irradiation in the orthotopic xenograft glioma model. In brief, this study offers a novel strategy for BPA delivery and may broaden the perspective on nanomedicine design for BNCT. 相似文献
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针对移动自组网端到端延迟在封闭形式分析方面的局限性,该文提出一种有效的针对无序传输,单副本两跳中继算法的网络延迟建模方案,并给出其严格的理论延迟上界。首先针对多种随机移动模型,证明了移动节点的相遇间隔时间可归纳为统一表达式。然后,综合分析了媒介竞争、流量竞争、排队延迟等问题,合理划分并精确求解出了各延迟关键时间段,从而构造了数据包排队服务模型。最后推导出移动自组网端到端延迟的封闭形式理论上界。仿真结果表明,该理论延迟与实验数据紧密吻合。 相似文献