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Search for "vesicles" in Full Text gives 81 result(s) in Beilstein Journal of Nanotechnology.
Functional diversity of resilin in Arthropoda
Beilstein J. Nanotechnol. 2016, 7, 1241–1259, doi:10.3762/bjnano.7.115
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
- micrographs demonstrated that PLL-γ-Fe2O3 or nanomag®-D-spio labeling did not affect the NSC ultrastructure and that both types of the nanoparticles were internalized into the cell vesicles rather than adhering to the cell surface (Figure 6). To determine the mechanism of the uptake of PLL-γ-Fe2O3 and nanomag
- . Transmission electron micrographs of NSCs labeled with PLL-γ-Fe2O3 (PLL, A, B) and nanomag®-D-spio (NM, C, D) nanoparticles, and unlabeled controls (E, F). Arrows indicate the macropinocytotic vesicles. Insets show macropinocytotic vesicles. Scale bar: 1 µm. Macropinocytosis is the mechanism of cellular uptake
Reconstitution of the membrane protein OmpF into biomimetic block copolymer–phospholipid hybrid membranes
Beilstein J. Nanotechnol. 2016, 7, 881–892, doi:10.3762/bjnano.7.80
- strength up to 10 times larger than that of phospholipid bilayers [18][19][20][21][22][23][24]. Vesicles formed by synthetic block polymers (polymersomes) can be modified in a similar way as vesicles made from phospholipids (liposomes) [25][26][27][28]. Although polymer membranes are generally thicker than
- DPhPC, block copolymer–phospholipid vesicles (lipopolymersomes) were prepared by electroformation [53] in aqueous solutions. Confocal fluorescence microscopy of vesicles dyed with fluorescent lipid (TopFluorPC) and nile red showed that blends of 90 mol % PIPEO block copolymers and 10 mol % DPhPC form
- giant vesicles (Figure 2A). Nile red was used as a general hydrophobic dye to visualize the membranes; TopFluorPC was used to assess possible phase separation between lipids and polymers. The molecular weight of PIPEO appeared to have no observable effect on the formation of vesicles despite the
Gold nanoparticles covalently assembled onto vesicle structures as possible biosensing platform
Beilstein J. Nanotechnol. 2016, 7, 655–663, doi:10.3762/bjnano.7.58
- bilayers with the aim of using this nanomaterial as platform for the future design of immunosensors. A novel methodology for the self-assembly of AuNPs onto large unilamellar vesicle structures is described. The vesicles were formed with 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1-undecanethiol
- (SH). After, the AuNPs photochemically synthesized in pure glycerol were mixed and anchored onto SH–DOPC vesicles. The data provided by voltammetry, spectrometry and microscopy techniques indicated that the AuNPs were successfully covalently anchored onto the vesicle bilayer and decorated vesicles
- exhibit a spherical shape with a size of 190 ± 10 nm. The developed procedure is easy, rapid and reproducible to start designing a possible immunosensor by using environmentally friendly procedures. Keywords: covalently decorated vesicles; gold nanoparticles; immunosensors design; synthesis
Active multi-point microrheology of cytoskeletal networks
Beilstein J. Nanotechnol. 2016, 7, 484–491, doi:10.3762/bjnano.7.42
- migration, reaction to external influences and transport of vesicles. In this work we showed the theoretical idea behind the method, the experimental implementation and in addition its limits via calculations of the SNR. These preliminary results open a wide field of applications in all kinds of different
Fabrication of hybrid graphene oxide/polyelectrolyte capsules by means of layer-by-layer assembly on erythrocyte cell templates
Beilstein J. Nanotechnol. 2015, 6, 2310–2318, doi:10.3762/bjnano.6.237
- layer-by-layer technique (LbL). Although the technique was originally developed for the alternating assembly of polyelectrolytes (PE) of opposite charge, LbL can be and has been extended to include particles, 2D layered materials, nanostructures, and lipid vesicles, which provide charged surfaces, or
Selective porous gates made from colloidal silica nanoparticles
Beilstein J. Nanotechnol. 2015, 6, 2105–2112, doi:10.3762/bjnano.6.215
- solution are able to form various types of aggregates, such as micelles and vesicles that can be employed to build novel nanomaterials [36][37]. Figure 1 reports the possible supramolecular organizations of amphiphiles when dissolved in solution. In particular, by changing the ratio between the silica
- order depending on the physicochemical properties of the block copolymer [38]. Next to the widespread spherical and short cylindrical (rod-like) micellar systems, also other types of supramolecular organizations were found, like lamellar sheets [39], worm-like systems [27] and vesicles [38]. When
Fulleropeptide esters as potential self-assembled antioxidants
Beilstein J. Nanotechnol. 2015, 6, 1065–1071, doi:10.3762/bjnano.6.107
- functionalized fullerenes are able to self-assemble into a plethora of supramolecular structures, such as spheres, nanotubes, vesicles, rods, nanowires, and nanofibers [9][10][11]. Also, formation of diverse morphologies of self-assembled fullerene derivatives under different external conditions has also been
Capillary and van der Waals interactions on CaF2 crystals from amplitude modulation AFM force reconstruction profiles under ambient conditions
Beilstein J. Nanotechnol. 2015, 6, 809–819, doi:10.3762/bjnano.6.84
- characterize a variety of nanoscale materials, from soft biomaterials (vesicles, viruses) [16][17], to organic thin films [18][19][20][21] and self-assembled monolayers [22] in liquid and in air, especially at those short separations where breakthrough events and sample mechanical deformations occur. However
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
- vesicles without any appreciable amount of change in the NP size and shape. In a similar way, Chen et al. [59] reported the synthesis of multifunctional magnetic and fluorescent nanocolloids. The synthesis began with the preparation of either inorganic QDs or organic semiconductors. These nanocomposites
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
- is approximate 600 nm in diameter (Supporting Information File 1, Figure S3). However, due to the point spread function of the microscope, we can assume that the actual size of the endosome is smaller. Accordingly, the observed vesicles might correspond to caveolae (d = 50–100 nm), rather than large
- directed phases, most likely corresponding to QD or QD-contained vesicles being transported by a motor protein along cytoskeletal filaments, and nondirected phases, during which the connection between QDs and filaments was lost. The presence of such trajectories for QD–kinesin constructs in HeLa cells was
- difference in size of the QD-containing vesicles (Figure 6b). Thus, internalized amine-functionalized CA–QDs were seemingly the largest cargos transported in the cellular interior, while carboxylated DHLA-coated and zwitterionic DPA-coated QDs were appreciably smaller, possibly internalized as single QDs or
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
- solvents, which are selective for only one of the blocks [7]. The formation of polymeric vesicles (polymerosomes) and spherical micelles is an interesting tool for the encapsulation of hydrophobic nanoparticles and since the critical micelle concentration (CMC) is comparatively low [8][9], a high stability
- -assembled vesicles and micelles in water, depending on the chosen block length ratio [19]. The high amount of present double bonds in the micelle core offers the possibility of radically initiated cross-linking of the structures or even microemulsion polymerizations to produce very dense capsules. Review
- the microscope image, the PI-b-PEG with 42 wt % PEG forms unilamellar vesicles in water in a size range between 2 and 5 µm. The sample containing 51 wt % PEG shows a big hydrodynamic diameter of about 250 nm with a broad size distribution in the DLS measurements (Figure 1B). This could be attributed
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
- single layers in each experiment. To calculate an average fluorescence intensity of SCIONs for a whole cell population, the overall fluorescence of the dye Alexa Fluor® 555 in every single cell was determined. Therefore the sensitivity of the nanoparticle channel was adjusted to the distinct vesicles
- of SCIONs by HeLa cells. This could be an indication for an unknown, alternative uptake mechanism, which is dependent on Caveolin-1 but independent from Dynamin 2. Because it is known, that Dynamin 2 plays an important role in the constriction of caveolae-coated vesicles from the inner cell membrane
- [27][43], another possible explanation is, that SCIONs accumulate in caveolae-coated vesicles at the cell membrane without their detachment when Dynamin 2 is depleted. These SCIONs would not have been removed before quantitative analysis. Further experiments have to be conducted to test these
Synthesis of boron nitride nanotubes and their applications
Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9
- the BNNTs in the primary human osteoblasts (hOBs) under the exposure of low frequency ultrasound (US) [80]. The BNNTs were wrapped with PLL for stabilization in water. Furthermore, they found that the PLL–BNNTs were localized in the cytoplasm in the vesicles. Although the experimental system was
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
- present experiments on a massive uptake of silica nanoparticles by giant unilamellar lipid vesicles (GUVs). We find that this uptake process depends on the size of the particles as well as on the thermodynamic state of the lipid membrane. Our findings are discussed in the light of several theoretical
- models and indicate that these models have to be extended in order to capture the interaction between nanomaterials and biological membranes correctly. Keywords: cells; endocytosis; engulfment; fission; gel phase; giant unilamellar lipid vesicles (GUV); lipid membranes; liquid phase; nanoparticle
- ; phosphocholines; uptake; vesicles; wrapping; Introduction Nanomaterials gain more and more importance in different industrial and scientific branches and the rising probability of accidental exposure of humans and their environment to nanoparticles gave rise to the development of the relatively new research
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
- material, e.g., lipoprotein particles, protein assemblies, viruses and NPs, these are typically encapsulated in vesicles and selectively transported into and out of the cells via endocytosis and exocytosis, respectively [9][10]. Depending on the size of the transport vesicle, cargo properties and the
- release of the vesicle from the parent membrane into the cytosolic compartment (Figure 1). This process is inhibited by dynasore. Clathrin creates a polyhedral lattice around newly forming vesicles and associates with the receptors in the membrane (that anchor the cargo) through adaptor proteins to
- long as internalized vesicles are continuously replaced by newly forming ones, the overall number of NP binding sites on the membrane in steady state should not be significantly affected by dynasore. Taken together, our inhibitor studies provided evidence that our small NPs are internalized via
Interaction of dermatologically relevant nanoparticles with skin cells and skin
Beilstein J. Nanotechnol. 2014, 5, 2363–2373, doi:10.3762/bjnano.5.245
- alterations were correlated with those findings (unpublished data). TEM studies confirmed intracellular uptake of AgNP accumulation in vesicles, most likely endosomes (Figure 2b). Toxicity of metal particles is widely attributed to the production of reactive oxygen species (ROS) [38] and oxidative stress
Nanobioarchitectures based on chlorophyll photopigment, artificial lipid bilayers and carbon nanotubes
Beilstein J. Nanotechnol. 2014, 5, 2316–2325, doi:10.3762/bjnano.5.240
- , Romania 10.3762/bjnano.5.240 Abstract In the last decade, building biohybrid materials has gained considerable interest in the field of nanotechnology. This paper describes an original design for bionanoarchitectures with interesting properties and potential bioapplications. Multilamellar lipid vesicles
- could open new perspectives for biomedical and biotechnological applications. The increased interest in use of phospholipids is due to the fact that they are basic structural components of biomembranes and artificial lipid membranes (liposomes). Liposomes are spherical, soft-matter vesicles composed of
- composition: peptone (Merck, 10 g/L), yeast extract (Biolife, 5 g/L), NaCl (Sigma-Aldrich, 5 g/L) and agar (Fluka, 20 g/L). Synthesis Liposome preparation The hydration method [22] of a thin DPPC film was used to obtain two kinds of multilamellar lipid vesicles (MLVs, 0.5 mM) with and without cholesterol in
Biopolymer colloids for controlling and templating inorganic synthesis
Beilstein J. Nanotechnol. 2014, 5, 2129–2138, doi:10.3762/bjnano.5.222
- , micelles, and vesicles, and on the other hand continuous scaffolds generated by gelling biopolymers. Keywords: biomacromolecules; biopolymer; colloid; nanoparticle; organic–inorganic hybrid; template; Introduction During the natural synthesis of inorganic matter in living organisms, referred to as
- “soft templates”, two subgroups can be considered: (C1) Biopolymer-stabilized spherical geometries (stabilized droplets, micelles, and vesicles) that confine the inorganic formation. (C2) Biopolymer structures acting as “scaffolds”, with more complex geometries than simple spheres. This is typically the
- as “soft templates” C1. Biopolymer-stabilized simple geometries (droplets, micelles, and vesicles): Surface-active polymers can assemble in solution and in heterophase systems to form defined geometries, most typically spherical, such as micelles, vesicles, or even stabilized droplets. As in the case
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
- without major mechanical stress for a cell is a useful tool to detect internalized metallic nanoparticles within cells [86]. As reported in the literature, the cellular uptake of nanoparticles is a conserved process during which extracellular substances are internalized by enclosing them into vesicles
- when the medium was depleted of serum (data not shown), indicating that at least the discharge of particles or ions from vesicles or other pathways at the cell surface membrane requires carrier molecules outside the cells. Interestingly, Panyam et al. have previously shown that the exocytosis of PLGA
Different endocytotic uptake mechanisms for nanoparticles in epithelial cells and macrophages
Beilstein J. Nanotechnol. 2014, 5, 1625–1636, doi:10.3762/bjnano.5.174
- of clathrin-coated vesicles (preventing clathrin-mediated endocytosis). Our data showed that a combination of several distinguishable endocytotic uptake mechanisms are involved in the uptake of 40 nm polystyrene nanoparticles in both the macrophage and epithelial cell line. Keywords: cell lines
- describes two different cellular uptake mechanisms: pinocytosis, which involves the uptake of fluids and molecules within small vesicles and phagocytosis, which is responsible for engulfing large particles (e.g., microorganisms and cell debris). Pinocytosis covers macropinocytosis, clathrin-mediated
- intracellular vesicles. However, some other studies have shown that NPs of different materials were detected in the intracellular space and/or free in the cytoplasm. Since they were not membrane-bound, alternative uptake routes for cellular uptake might exist [22][46][59][63]. Possible uptake mechanisms such as
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
- . [41], cf. Figure 3), all of them have in common that the NPs are surrounded by membrane. Pinching-off of the membrane-surrounded NPs from the cell plasma membrane leaves the NPs incorporated into intracellular vesicles. These vesicles undergo a cascade of intracellular trafficking steps passing the
- NPs to more and more acidic vesicles [42][43], which also comprise enzymes specialized in digesting nutrition (and thus also parts of the NPs are digested in the lysosome [44][45]). In other words, after incorporation, the majority of NPs is not “free” in the cytosol, but inside intracellular vesicles
- (cf. Figure 4). Inside those intracellular vesicles the NPs are in an environment (acidic pH, enzymes) completely different from that in the cytosol (cf. Figure 5). Endocytosis and the endosomal escape dilemma have to be taken into account in particular concerning the delivery applications of NPs, in
Mimicking exposures to acute and lifetime concentrations of inhaled silver nanoparticles by two different in vitro approaches
Beilstein J. Nanotechnol. 2014, 5, 1357–1370, doi:10.3762/bjnano.5.149
- taken up by cells and to determine the shape and agglomeration state of the NPs. The cells were exposed in submerged conditions to 20 µg Ag/mL Ag NPs and fixed 24 h after exposure for TEM. In Figure 3 large aggregates attached to cells and within vesicles are visible in those cells present in the upper
- study we used the ALICE system to nebulize well-characterized [45][46] PVP-capped 100 nm Ag NPs. The majority of the 100 nm PVP-capped Ag NPs were found as aggregates inside vesicles, a finding which was similar for the 20 nm Ag NPs [44]. The aggregation was not as prominent for 15 nm Au NPs [42], and
- black marked boxes (A–C) revealed Ag NP aggregates attached to cells (A) and in vesicles of cells (B, C). Extracellular LDH release was quantified relative to the untreated control (reference: red dashed line = 1.0) 4 h (grey bars) and 24 h (black bars), respectively, after exposure. Air–liquid
Model systems for studying cell adhesion and biomimetic actin networks
Beilstein J. Nanotechnol. 2014, 5, 1193–1202, doi:10.3762/bjnano.5.131
- be incorporated into lipid vesicles, too. We here review the mechanisms of integrin-mediated cell adhesion and recent advances in the field of minimal cells towards synthetic adhesion. We focus on reconstituting integrins into lipid structures for mimicking cell adhesion and on the incorporation of
- very difficult to selectively study a single aspect of natural cells. In recent years, minimal cells with reduced molecular complexity have gained increasing importance as model systems for living cells. Such synthetic cells often consist of lipid vesicles with various incorporated proteins, which are
- mechanisms of integrin-mediated cell adhesion and the interaction of talin with lipid vesicles. 1. The role of integrins in cell adhesion Cellular adhesion is an important mechanism, which enables cells to bind to the extracellular matrix and to surrounding cells. This process is crucial in regulating cell
Manipulation of isolated brain nerve terminals by an external magnetic field using D-mannose-coated γ-Fe2O3 nano-sized particles and assessment of their effects on glutamate transport
Beilstein J. Nanotechnol. 2014, 5, 778–788, doi:10.3762/bjnano.5.90
- (synaptosomes). Also, the membrane potential of synaptosomes and acidification of synaptic vesicles was not changed as a result of the application of D-mannose-coated γ-Fe2O3 nanoparticles. This was demonstrated with the potential-sensitive fluorescent dye rhodamine 6G and the pH-sensitive dye acridine orange
- properties. Synaptic vesicles, which are acidic compartments of nerve terminals, store neurotransmitters and release their contents by exocytosis upon stimulation. Acidification of synaptic vesicles accompanied by loading of the neurotransmitters appears to be their common property [14]. The active transport
- of not only glutamate, but also acetylcholine, monoamines, and γ-aminobutyric acid/glycine to synaptic vesicles is accomplished by vesicular transporters of the neurotransmitters, whose function depends on the proton electrochemical gradient ΔμH+ generated by V-ATPase that pumps protons into the
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