共查询到13条相似文献,搜索用时 15 毫秒
1.
An Experimental and Computational Approach to the Development of ZnO Nanoparticles that are Safe by Design 下载免费PDF全文
Tu C. Le Hong Yin Rui Chen Yandong Chen Lin Zhao Philip S. Casey Chunying Chen David A. Winkler 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(26):3568-3577
Zinc oxide nanoparticles have found wide application due to their unique optoelectronic and photocatalytic characteristics. However, their safety aspects remain of critical concern, prompting the use of physicochemical modifications of pristine ZnO to reduce any potential toxicity. However, the relationships between these modifications and their effects on biology are complex and still relatively unexplored. To address this knowledge gap, a library of 45 types of ZnO nanoparticles with varying particle size, aspect ratio, doping type, doping concentration, and surface coating is synthesized, and their biological effects measured. Three biological assays measuring cell damage or stress are used to study the responses of human umbilical vein endothelial cells (HUVECs) or human hepatocellular liver carcinoma cells (HepG2) to the nanoparticles. These experimental data are used to develop quantitative and predictive computational models linking nanoparticle properties to cell viability, membrane integrity, and oxidative stress. It is found that the concentration of nanoparticles the cells are exposed to, the type of surface coating, the nature and extent of doping, and the aspect ratio of the particles make significant contributions to the cell toxicity of the nanoparticles tested. Our study shows that it is feasible to generate models that could be used to design or optimize nanoparticles with commercially useful properties that are also safe to humans and the environment. 相似文献
2.
Hung‐Jen Yen Shan‐hui Hsu Ching‐Lin Tsai 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(13):1553-1561
The immunological response of macrophages to physically produced pure Au and Ag nanoparticles (NPs) (in three different sizes) is investigated in vitro. The treatment of either type of NP at ≥10 ppm dramatically decreases the population and increases the size of the macrophages. Both NPs enter the cells but only AuNPs (especially those with smaller diamter) up‐regulate the expressions of proinflammatory genes interlukin‐1 (IL‐1), interlukin‐6 (IL‐6), and tumor necrosis factor (TNF‐α). Transmission electron microscopy images show that AuNPs and AgNPs are both trapped in vesicles in the cytoplasma, but only AuNPs are organized into a circular pattern. It is speculated that part of the negatively charged AuNPs might adsorb serum protein and enter cells via the more complicated endocytotic pathway, which results in higher cytotoxicity and immunological response of AuNPs as compared to AgNPS. 相似文献
3.
Medical applications of nanoparticles (NPs) require understanding of their interactions with living systems in order to control their physiological response, such as cellular uptake and cytotoxicity. When NPs are exposed to biological fluids, the adsorption of extracellular proteins on the surface of NPs, creating the so‐called protein corona, can critically affect their interactions with cells. Here, the effect of surface coating of silver nanoparticles (AgNPs) on the adsorption of serum proteins (SPs) and its consequence on cellular uptake and cytotoxicity in mouse embryonic fibroblasts are shown. In particular, citrate‐capped AgNPs are internalized by cells and show a time‐ and dose‐dependent toxicity, while the passivation of the NP surface with an oligo(ethylene glycol) (OEG)‐alkanethiol drastically reduces their uptake and cytotoxicity. The exposure to growth media containing SPs reveals that citrate‐capped AgNPs are promptly coated and stabilized by proteins, while the AgNPs resulting from capping with the OEG‐alkanethiol are more resistant to adsorption of proteins onto their surface. Using NIH‐3T3 cultured in serum‐free, the key role of the adsorption of SPs onto surface of NPs is shown as only AgNPs with a preformed protein corona can be internalized by the cells and, consequently, carry out their inherent cytotoxic activity. 相似文献
4.
Yu Pan Annika Leifert David Ruau Sabine Neuss Jörg Bornemann Günter Schmid Wolfgang Brandau Ulrich Simon Willi Jahnen‐Dechent 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(18):2067-2076
Gold nanoparticles (AuNPs) are generally considered nontoxic, similar to bulk gold, which is inert and biocompatible. AuNPs of diameter 1.4 nm capped with triphenylphosphine monosulfonate (TPPMS), Au1.4MS, are much more cytotoxic than 15‐nm nanoparticles (Au15MS) of similar chemical composition. Here, major cell‐death pathways are studied and it is determined that the cytotoxicity is caused by oxidative stress. Indicators of oxidative stress, reactive oxygen species (ROS), mitochondrial potential and integrity, and mitochondrial substrate reduction are all compromised. Genome‐wide expression profiling using DNA gene arrays indicates robust upregulation of stress‐related genes after 6 and 12 h of incubation with a 2 × IC50 concentration of Au1.4MS but not with Au15MS nanoparticles. The caspase inhibitor Z‐VAD‐fmk does not rescue the cells, which suggests that necrosis, not apoptosis, is the predominant pathway at this concentration. Pretreatment of the nanoparticles with reducing agents/antioxidants N‐acetylcysteine, glutathione, and TPPMS reduces the toxicity of Au1.4MS. AuNPs of similar size but capped with glutathione (Au1.1GSH) likewise do not induce oxidative stress. Besides the size dependency of AuNP toxicity, ligand chemistry is a critical parameter determining the degree of cytotoxicity. AuNP exposure most likely causes oxidative stress that is amplified by mitochondrial damage. Au1.4MS nanoparticle cytotoxicity is associated with oxidative stress, endogenous ROS production, and depletion of the intracellular antioxidant pool. 相似文献
5.
6.
5 nm Silver Nanoparticles Amplify Clinical Features of Atopic Dermatitis in Mice by Activating Mast Cells 下载免费PDF全文
HanGoo Kang Seungjae Kim Kwang Hoon Lee Shan Jin Seo Hyeong Kim Kangtaek Lee Hyungjoon Jeon Young‐Geon Song Sang‐Won Lee Jinwon Seo Soomin Park In‐Hong Choi 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(9)
The triggering effect of silver nanoparticles (NPs) on the induction of allergic reactions is evaluated, by studying the activation of mast cells and the clinical features of atopic dermatitis in a mouse model. Granule release is induced in RBL‐2H3 mast cells by 5 nm, but not 100 nm silver NPs. Increases in the levels of reactive oxygen species (hydrogen peroxide and mitochondrial superoxide) and intracellular Ca++ in mast cells are induced by 5 nm silver NPs. In a mouse model of atopic dermatitis induced by a mite allergen, the skin lesions are more severe and appear earlier in mice treated simultaneously with 5 nm silver NPs and allergen compared with mice treated with allergen alone or 100 nm silver NPs and allergen. The histological findings reveal that number of tryptase‐positive mast cells and total IgE levels in the serum increase in mice treated with 5 nm silver NPs and allergen. The results in this study indicate that cotreatment with 5 nm silver NPs stimulates mast cell degranulation and induces earlier and more severe clinical alterations in allergy‐prone individuals. 相似文献
7.
Shailendra Shakya Yaping He Xiaohong Ren Tao Guo Abi Maharjan Ting Luo Tingting Wang Ramesh Dhakhwa Balmukunda Regmi Haiyan Li Ruxandra Gref Jiwen Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(27)
The challenge of bacterial infection increases the risk of mortality and morbidity in acute and chronic wound healing. Silver nanoparticles (Ag NPs) are a promising new version of conventional antibacterial nanosystem to fight against the bacterial resistance in concern of the drug discovery void. However, there are several challenges in controlling the size and colloidal stability of Ag NPs, which readily aggregate or coalesce in both solid and aqueous state. In this study, a template‐guided synthesis of ultrafine Ag NPs of around 2 nm using water‐soluble and biocompatible γ‐cyclodextrin metal‐organic frameworks (CD‐MOFs) is reported. The CD‐MOF based synthetic strategy integrates AgNO3 reduction and Ag NPs immobilization in one pot achieving dual functions of reduced particle size and enhanced stability. Meanwhile, the synthesized Ag NPs are easily dispersible in aqueous media and exhibit effective bacterial inhibition. The surface modification of cross‐linked CD‐MOF particles with GRGDS peptide boosts the hemostatic effect that further enhances wound healing in synergy with the antibacterial effect. Hence, the strategy of ultrafine Ag NPs synthesis and immobilization in CD‐MOFs together with GRGDS modification holds promising potential for the rational design of effective wound healing devices. 相似文献
8.
分别以天草柑橘皮提取液作为绿色还原剂,硼氢化钠(NaBH4)作为化学还原剂制备两种纳米银(G-AgNPs和C-AgNPs),对二者的还原率、粒径尺寸及形貌、结晶结构以及组成成分进行表征,比较它们在分散性、抗菌性和抗氧化性等性能上的差异。结果表明,两种还原剂对Ag+的还原率都可达90%以上。G-AgNPs与C-AgNPs均为球形或类球形的面心立方结构晶体,但G-AgNPs的粒径尺寸分布较窄,平均粒径与粒度中值(D50)分别为29.81 nm和28.21 nm,小于C-AgNPs。同时,G-AgNPs表面吸附了橘皮提取液中的活性成分,减少了粒子间的团聚,因而相较于C-AgNPs有更好的分散性和稳定性。G-AgNPs与C-AgNPs对食源性革兰氏阳性菌(金黄色葡萄球菌、枯草芽孢杆菌)和革兰氏阴性菌(大肠杆菌、伤寒沙门氏菌)均表现出较强的生长抑制效果,但G-AgNPs的抑菌效果总体优于C-AgNPs。同时,由于表面活性成分的存在,G-AgNPs对亚甲基蓝(Methylene blue,MB)的脱色率显著高于C-AgNPs,具有很强的抗氧化活性。G-AgNPs所具有的良好分散性、抗菌性和抗氧化性使得它们成为一种理想的纳米填料,在功能性复合材料的制备中具有较大的应用潜力。 相似文献
9.
10.
My Kieu Ha Sook Jin Kwon Jang‐Sik Choi Nguyen Thanh Nguyen Jaewoo Song Yangsoon Lee Young‐Eun Kim Incheol Shin Jin‐Wu Nam Tae Hyun Yoon 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(21)
Understanding the interactions between nanoparticles (NPs) and human immune cells is necessary for justifying their utilization in consumer products and biomedical applications. However, conventional assays may be insufficient in describing the complexity and heterogeneity of cell–NP interactions. Herein, mass cytometry and single‐cell RNA‐sequencing (scRNA‐seq) are complementarily used to investigate the heterogeneous interactions between silver nanoparticles (AgNPs) and primary immune cells. Mass cytometry reveals the heterogeneous biodistribution of the positively charged polyethylenimine‐coated AgNPs in various cell types and finds that monocytes and B cells have higher association with the AgNPs than other populations. scRNA‐seq data of these two cell types demonstrate that each type has distinct responses to AgNP treatment: NRF2‐mediated oxidative stress is confined to B cells, whereas monocytes show Fcγ‐mediated phagocytosis. Besides the between‐population heterogeneity, analysis of single‐cell dose–response relationships further reveals within‐population diversity for the B cells and naïve CD4+ T cells. Distinct subsets having different levels of cellular responses with respect to their cellular AgNP doses are found. This study demonstrates that the complementary use of mass cytometry and scRNA‐seq is helpful for gaining in‐depth knowledge on the heterogeneous interactions between immune cells and NPs and can be incorporated into future toxicity assessments of nanomaterials. 相似文献
11.
12.
K. Boboridis A. Seifter A. W. Obst D. Basak 《International Journal of Thermophysics》2004,25(4):1187-1202
The radiance temperatures at four wavelengths (in the range of 1500 to 5000 nm) of tin, zinc, aluminum, and silver at their respective melting points were measured by a pulse-heating technique using a high-speed fiber-coupled four-wavelength infrared pyrometer. The method is based on rapid resistive self-heating of a sample from room temperature to its melting point in less than 1 s while measuring the radiance emitted by it in four wavelength bands as a function of time. A plateau in the recorded radiance-versus-time traces indicates melting of the sample. The melting-point radiance temperatures for a given sample are determined by averaging the measured temperatures along the plateau at each wavelength. The melting-point radiance temperatures for each metal are, in turn, determined by averaging results for several samples. The normal spectral emittances at the melting transition of each metal are derived from the measured radiances at each wavelength and the published values of the thermodynamic (true) melting temperatures. 相似文献