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Search for "internalization" in Full Text gives 81 result(s) in Beilstein Journal of Nanotechnology.
Viability and proliferation of endothelial cells upon exposure to GaN nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 1330–1337, doi:10.3762/bjnano.7.124
- . Since each cell division reduces the number of the incorporated GaN nanoparticles by 50%, the load of GaN nanoparticles in a single cell diminishes with time. The growth of endothelial cells on top of fixed nanoparticles avoids the internalization process of nanoparticles by cells. Surface
On the pathway of cellular uptake: new insight into the interaction between the cell membrane and very small nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 1296–1311, doi:10.3762/bjnano.7.121
- diameter tested a different membrane morphology during uptake can be observed and that the amount of particles entering in one event is different for the three sizes. Silica particles with a diameter of 22 nm show single-particle internalization with a membrane wrapped around the particles in the cytosol
Improved biocompatibility and efficient labeling of neural stem cells with poly(L-lysine)-coated maghemite nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 926–936, doi:10.3762/bjnano.7.84
- their cellular uptake, the mechanism of internalization, cytotoxicity, viability and proliferation of neural stem cells, and compared them to the commercially available dextran-coated nanomag®-D-spio nanoparticles. Results: Light microscopy of Prussian blue staining revealed a concentration-dependent
- of neural stem cells. Cytochalasine D blocked the cellular uptake of nanoparticles indicating an actin-dependent process, such as macropinocytosis, to be the internalization mechanism for both nanoparticle types. Finally, immunocytochemistry analysis of neural stem cells after treatment with poly(L
- tracking [16]. Biocompatible polymers are used to modify the surface of nanoparticles, prevent their agglomeration and facilitate internalization. The most widely used coating for surface modification of nanoparticles is dextran, which promotes nanoparticle internalization, in particular in different
Silica-coated upconversion lanthanide nanoparticles: The effect of crystal design on morphology, structure and optical properties
Beilstein J. Nanotechnol. 2015, 6, 2290–2299, doi:10.3762/bjnano.6.235
- in OM, serving as both solvent and surface binding ligand [20]. Because the particle size plays a key role in biomedical applications, e.g., for internalization of nanoparticles by cells of the reticuloendothelial system [32], the effects of both reaction temperature and time were investigated to
Natural and artificial binders of polyriboadenylic acid and their effect on RNA structure
Beilstein J. Nanotechnol. 2015, 6, 1338–1347, doi:10.3762/bjnano.6.138
- delivery of these molecular tools can be selectively directed towards cancer cells and, after their internalization, the anticancer activity could be exerted either by the entire conjugate or by the free binder after loss of the targeting agent. Thus, due to the importance of poly(rA) binders, for example
PLGA nanoparticles as a platform for vitamin D-based cancer therapy
Beilstein J. Nanotechnol. 2015, 6, 1306–1318, doi:10.3762/bjnano.6.135
- calcitriol remained stable at release conditions throughout the experiment period. Cellular uptake of PLGA NPs and calcitriol-induced morphological changes The internalization of fluorescent C6–calcitriol–PLGA NPs by S2-013, hTERT-HPNE and A549 cells was evaluated by confocal microscopy. Counterstaining of
- pancreatic cell lines, S2-013 and hTERT-HPNE, was reported. The in vitro proliferation assay showed that the encapsulation of calcitriol enhanced its antiproliferative activity. The efficient cell internalization by an endocytosis mechanism of PLGA NPs and their rapid endo-lysosomal escape observed in this
- , this mechanism of NP internalization avoids calcitriol transport out of cells mediated by P-glycoprotein involved in the MDR problem. It was previously established that after internalization, PLGA NPs suffer a charge change triggered by the acidic medium of late endosome/lysosome. This leads to the
Protein corona – from molecular adsorption to physiological complexity
Beilstein J. Nanotechnol. 2015, 6, 857–873, doi:10.3762/bjnano.6.88
- cellular uptake. A possible contribution to this observation is that, in presence of free proteins, the cellular endocytosis machinery was also occupied with internalization of the freely dissolved protein. However, intriguing differences were found between the effects of the different coronae, essentially
- all consisting of HSA with just minor chemical modifications as described above. Internalization of HSAam-coated NPs by the cells was completely suppressed within the sensitivity limits of their experiment. In addition the time-dependent NP uptake by HeLa cells was investigated, using spinning disk
- also determined for internalization of NPs and varied less than a factor of 2. The combined interpretation of their data, allowed them to deduce that the overall uptake is controlled by the binding of the NP to the cell membrane. These findings will clearly help to design NPs for directed cellular
Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy
Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57
- cancer cells were treated and monitored under a fluorescence microscope at 405 nm excitation. Intense green fluorescence was observed from cancer cells which confirmed the internalization of NPs. Similarly, Pinho et al. [15] reported the synthesis of a bimodal MRI probe by embedding two lanthanide metal
- internalized by RAW 264.7 cells. An increase in the intensity of T1-weighted MRI images of cellular pellets was observed when these nanocomposites were treated with the cells. The internalization into the cells was also monitored by fluorescence microscopy at 393 nm excitation. Recently, there has been a
Pulmonary surfactant augments cytotoxicity of silica nanoparticles: Studies on an in vitro air–blood barrier model
Beilstein J. Nanotechnol. 2015, 6, 517–528, doi:10.3762/bjnano.6.54
- extracellular ROS production or could trigger a cellular ROS production following internalization of the aSNPs. Extracellular ROS production likewise causes membranolysis [33][37][39][40]. To verify this hypothesis aSNP-stimulated A549 with and without Alveofact® was checked for ROS over a period of 20 min to
Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization
Beilstein J. Nanotechnol. 2015, 6, 300–312, doi:10.3762/bjnano.6.28
- field of nanoparticles, many studies demonstrated a high impact of the shape, size and surface charge, which is determined by the functionalization, of nanoparticles on cell viability and internalization into cells. This work focused on the comparison of three different nanoparticle types to give a
- endothelial cells. These findings are attributed to a rapid internalization of the NH2-functionalized nanoparticles in combination with the damage of intracellular membranes. Interestingly, the endocytotic pathway seems to be a size-dependent process whereas nanoparticles with a size of 20 nm are internalized
- by caveolae-mediated endocytosis and nanoparticles with a size of 40 nm are taken up by clathrin-mediated internalization and macropinocytosis. Our results can be summarized to formulate five general rules, which are further specified in the text and which determine the biocompatibility of
The effect of surface charge on nonspecific uptake and cytotoxicity of CdSe/ZnS core/shell quantum dots
Beilstein J. Nanotechnol. 2015, 6, 281–292, doi:10.3762/bjnano.6.26
- cell (in this time regime). In order to estimate the extent of QD internalization within MDCKII cells upon exposure, and to investigate the kinetics of their nonspecific interaction, a series of fluorescence images of different areas of MDCKII confluent layers was acquired during 24 hours of exposure
- interior during the first 6 h after addition of QDs. For longer exposure times, the cell interior close to the nucleus displays more particles (Figure 3c). In order to elucidate the mechanism of QD internalization by MDCKII cells, we studied nonspecific interactions between QDs and inhibitor-treated MDCK
Tailoring the ligand shell for the control of cellular uptake and optical properties of nanocrystals
Beilstein J. Nanotechnol. 2015, 6, 232–242, doi:10.3762/bjnano.6.22
- unspecific interactions with cells, like macrophages, epithelic or endothelic cells [32]. For macrophages the internalization process follows the typical steps of phagocytosis, which is controlled by the adsorption of specific proteins on the surface of the nanocontainer. Hydrophobic and charged particles in
Caveolin-1 and CDC42 mediated endocytosis of silica-coated iron oxide nanoparticles in HeLa cells
Beilstein J. Nanotechnol. 2015, 6, 167–176, doi:10.3762/bjnano.6.16
- development of new therapies for numerous diseases. For example iron oxide nanoparticles are in clinical use already in the thermotherapy of brain cancer. Although it has been shown, that tumor cells take up these particles in vitro, little is known about the internalization routes. Understanding of the
- on the surface characteristics of the nanoparticles and the experimental design. Knockdown of CDC42 showed a 46% decrease of the internalization of PEGylated SPIONs within 24 h incubation time. Knockdown of Dynamin 2, Flotillin-1, Clathrin and PIP5Kα caused no or only minor effects. Hence endocytosis
- of the SCIONs was chosen after preliminary experiments. It could be shown that 5 µg Fe/mL provides the lowest background fluorescence combined with a good intracellular signal. In both setups the cell culture media contains SCIONs in excess to the internalization rate of the cells. Afterward cells
The distribution and degradation of radiolabeled superparamagnetic iron oxide nanoparticles and quantum dots in mice
Beilstein J. Nanotechnol. 2015, 6, 111–123, doi:10.3762/bjnano.6.11
- cellular internalization and processing of polymer-coated Qdots and SPIOs was gained by cell culture. For comparison of the in vivo data, these studies were made with J774 cells (a murine macrophage cell line). The cells were incubated with polymer-coated Qdots for 2 h, then the nanoparticles were removed
Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating
Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257
- cell migration and no significant particle internalization occurred. Concerning cell adhesion and spreading as compared to cell growth on bare substrates after 3 days of incubation, a reduction by 45% and 95%, respectively, for the surfactant particle coating was observed, whereas the amino-terminated
- special functionality), this study is focused on the impact of basolateral exposure of gold nanoparticles on epithelial cells. Here, epithelial cells were exposed to nanoparticles adsorbed onto a surface. Since MDCK II cells exhibit caveolae only basolaterally, it is conceivable that internalization is
- nanoparticle surface, and direct chemical binding are possible candidates. For an internalization of particles into the cell, the contact strength between the particle and the membrane must overcome the van der Waals forces, keeping the particles immobilized on the substrate. In regions where the cell membrane
Intake of silica nanoparticles by giant lipid vesicles: influence of particle size and thermodynamic membrane state
Beilstein J. Nanotechnol. 2014, 5, 2468–2478, doi:10.3762/bjnano.5.256
- massive particle uptake takes place. Figure 3 illustrates this situation. During the uptake process, the vesicle radius, i.e., the membrane area shrinks continuously, whereas the intravesicular particle concentration increases. Furthermore, the particles become visible after internalization in the optical
- internalization of particle agglomerates. Taken together, further experiments will be necessary to exclude these mentioned effects. The relevance of the membrane bending stiffness for the observed phenomena still remains questionable. Especially for the large 123 nm particles, it will probably play a minor role
- the typical relaxation time of membrane defects. Both parameters are very important for uptake processes. The facts, that massive internalization of particles can be driven by unspecific interaction of lipid membranes and that this is dependent on the phase state of the membrane are highly relevant
Functionalized polystyrene nanoparticles as a platform for studying bio–nano interactions
Beilstein J. Nanotechnol. 2014, 5, 2403–2412, doi:10.3762/bjnano.5.250
- recognition and internalization of particulate matter including nanoparticles. As a consequence, macrophages accumulate with time a main portion of nanoparticles incorporated by the body [25]. Thus, the clinically approved superparamagnetic iron oxide (SPIO) MRI contrast agent ResovistTM is taken up after
- implicated in the development of atherosclerosis [27]. In vitro studies showed that this receptor is engaged in the internalization of negatively charged ResovistTM, a SPIO of 20–60 nm in size, by human macrophages via clathrin-mediated endocytosis. Hence, the uptake of negatively charged nanoparticles of
- of specific receptors engaged in the uptake might dictate the rate of particle internalization by a cell. We have shown that in the presence of serum, macrophages take up nanoparticles by phagocytosis using specific interaction with an antibody receptor CD64, which is specifically expressed on the
Nanoparticle interactions with live cells: Quantitative fluorescence microscopy of nanoparticle size effects
Beilstein J. Nanotechnol. 2014, 5, 2388–2397, doi:10.3762/bjnano.5.248
- . By using spinning disk confocal microscopy in combination with quantitative image analysis, we studied the time courses of NP association with the cell membrane and subsequent internalization. NPs with diameters of less than 10 nm were observed to accumulate at the plasma membrane before being
- machinery in order to trigger the subsequent internalization. Keywords: cell membrane; endocytosis; fluorescence microscopy; nanoparticle; size effect; Introduction Understanding the interaction between engineered nanomaterials and living matter has attracted increasing attention in recent years
- it determines the biological identity of the NP. The key role of a cellular membrane is to provide a strict separation between the cytosol and the extracellular environment, and to selectively control the flow of ions and molecules into and out of the cell. For internalization of larger chunks of
Interaction of dermatologically relevant nanoparticles with skin cells and skin
Beilstein J. Nanotechnol. 2014, 5, 2363–2373, doi:10.3762/bjnano.5.245
- and subsequent isolation of keratinocytes and Langerhans cells, only the internalization of 42 nm, but not of 75 or 200 nm particles could be identified. Interestingly, the size limit for penetration and cellular uptake appears to differ among different particle types. In previous studies of our
- groups, we observed penetration and cellular uptake of fluorescent polystyrene particles ranging from 40–200 nm in diameter after skin surface stripping in murine and human skin [11][12]. Furthermore, the internalization of a fluorescent vaccinia virus vector (diameter approx. 290 nm) could be
- tissue raises the question whether nanomaterials ever have the chance to translocate the skin barrier on the single-particle level, or how the adsorption of skin surface material and secondary changes in particle properties will affect penetration and internalization by cells. Also, results obtained from
Anticancer efficacy of a supramolecular complex of a 2-diethylaminoethyl–dextran–MMA graft copolymer and paclitaxel used as an artificial enzyme
Beilstein J. Nanotechnol. 2014, 5, 2293–2307, doi:10.3762/bjnano.5.238
- the modulation of the AP-GA-triggered stress responses in cells because of the differences in the internalization mechanism, subcellular localization, and concentration gradients in cells [5][6]. Above all, the DDS complex must be not degraded in cells and act as an intact object. Nishiyama et al. [7
Effect of silver nanoparticles on human mesenchymal stem cell differentiation
Beilstein J. Nanotechnol. 2014, 5, 2058–2069, doi:10.3762/bjnano.5.214
- of silver under these experimental conditions. In summary, the internalization of nano-silver into stem cells had a significant influence on diverse aspects of cellular functions. Therefore, more studies are needed to investigate the effects of nano-silver in directing stem cell behavior in order to
PVP-coated, negatively charged silver nanoparticles: A multi-center study of their physicochemical characteristics, cell culture and in vivo experiments
Beilstein J. Nanotechnol. 2014, 5, 1944–1965, doi:10.3762/bjnano.5.205
- internalization of silver nanoparticles in astrocytes as in the cell types discussed above (Figure 11), inhibitors of macropinocytosis and endosomal trafficking (chloroquine and amiloride) at least partially lower the accumulation of silver nanoparticles [108]. Accumulated silver nanoparticles appear to be quite
Influence of surface-modified maghemite nanoparticles on in vitro survival of human stem cells
Beilstein J. Nanotechnol. 2014, 5, 1732–1737, doi:10.3762/bjnano.5.183
- biological application of foreign objects, the surface of the nanoparticles has to be coated by a biocompatible shell to prevent undesirable interactions of particles with the environment and to enable their internalization by the cells. At the same time coating avoids particle aggregation. Last but not
- least, the surface shell of the magnetic cores has to participate actively in the uptake of the conjugates, proteins and/or antibodies. Internalization (transfection) agents [10] or specific targeting groups [11][12] are therefore often bound to the particles in order to support their uptake by the
Precise quantification of silica and ceria nanoparticle uptake revealed by 3D fluorescence microscopy
Beilstein J. Nanotechnol. 2014, 5, 1616–1624, doi:10.3762/bjnano.5.173
- medical treatment, and also for a correct risk assessment of nanoparticles. In both cases, knowledge regarding the kinetics of particle internalization gives the dose as a function of the time and allows for the investigation of a variety of parameters on that might influence the uptake behavior. Typical
- nanoparticles, possibly influenced by cell division. Particle_in_ell-3D can be applied to investigate the dose-dependent effects for the risk assessment of nanoparticles. Additionally, this method can be used to study which factors are determinant for the successful attachment, internalization and cargo release
In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?
Beilstein J. Nanotechnol. 2014, 5, 1477–1490, doi:10.3762/bjnano.5.161
- ., "yes" or "no"), but rather are based on different kinetics. However, non-adhesive cell lines, i.e., cell suspensions, can be different and examples in which no significant internalization of NPs happened are reported [31]. Coming back to adhesive cell-lines, the first step in NP internalization
- parameters are typically asked over the time course required for NP internalization and subcellular localization, and are not tracked over long time courses. It is generally accepted that NPs are partitioned during cell division, in which they are passed to the daughter cells [76][77]. Such dilution effect
- internalization? As mentioned before, virtually all NPs are spontaneously internalized by adherent cells, mainly cell lines, that are usually grown on a certain support and covered with cell culture medium under static conditions. In this case, NPs in the medium can directly access cells, and issues like tissue
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