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Search for "vesicles" in Full Text gives 91 result(s) in Beilstein Journal of Nanotechnology.
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- alterations were correlated with those findings (unpublished data).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
Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone
Beilstein J. Nanotechnol. 2014, 5, 610–621, doi:10.3762/bjnano.5.72
- spectroscopic studies suggested that Ca-deposition in osteoblasts starts intracellularly in calcium-rich vesicles that substantially contribute to the formation of bone apatite [27]. Both calcium phosphate formation [28] and calcium carbonate deposition [29] are exergonic processes that, in turn, are
- phosphate linked by energy-rich phosphodiester bonds. Moreover, polyP turned out to be an inducer of osteoblast-specific alkaline phosphatase. This finding is interesting in view of published data indicating that intracellularly polyP might be formed in the vesicles of bone-forming cells as a Ca salt, which
Morphological characterization of fullerene–androsterone conjugates
Beilstein J. Nanotechnol. 2014, 5, 374–379, doi:10.3762/bjnano.5.43
- and hydrophilic moieties, form spherical vesicles known as “buckysomes” in aqueous media [13]. The same behavior has also been observed by Conyers et al. [14] and Martin et al. [15] for other fullerene derivatives. As representative examples, the pentamethyl[60]fullerene salt Me5C60K and the
- unilamellar vesicles, and form spherical aggregates with a variety of sizes, but with a well-defined spherical shape. In general, when the C60 moiety was attached into the D rind (IIa,b) instead of the A ring (Ia,b) of the androsterone moiety, larger aggregates were obtained. These results are a consequence
- of the difference in hydrophilicity of the androsterone moieties in both diasteromeric pairs. The presence of a carbonyl group in Ia,b instead of a less polar group such as acetoxy in IIa,b, promoted the formation of smaller vesicles. Dynamic light scattering DLS measurements gave further information
Nanoscopic surfactant behavior of the porin MspA in aqueous media
Beilstein J. Nanotechnol. 2013, 4, 278–284, doi:10.3762/bjnano.4.30
- Abstract The mycobacterial porin MspA is one of the most stable channel proteins known to date. MspA forms vesicles at low concentrations in aqueous buffers. Evidence from dynamic light scattering, transmission electron microscopy and zeta-potential measurements by electrophoretic light scattering indicate
- in aqueous phase. Engelhardt et al. have established by using high-resolution TEM that MspA forms micelles and linear aggregates on surfaces showing a zipper-like pattern in the absence of surfactants, and that MspA is able to reconstitute in dimyristoyl phosphatidylcholine (DMPC) vesicles in the
- behavior of MspA in aqueous buffers, further expanding the pioneering work of Engelhardt et al. In 1× PBS (phosphate-buffered saline), MspA is capable of forming vesicles in the absence of added surfactant. Owing to the great thermal stability of MspA [3], we were able to study the influence of ionic
Large-scale analysis of high-speed atomic force microscopy data sets using adaptive image processing
Beilstein J. Nanotechnol. 2012, 3, 747–758, doi:10.3762/bjnano.3.84
- mass of lipid into glass vials and dissolved with chloroform. The chloroform was evaporated off with dry nitrogen gas, leaving a thin film on the glass vial. The film was hydrated with Milli-Q water (Millipore, Billerica, MA, USA), generating large multilaminar vesicles (LMVs). The LMVs were then
- sonicated with a probe sonicator (BioLogics Inc, Manassas, VA, USA) to generate small unilaminar vesicles (SUVs). The SUVs were centrifuged to remove metal particles left from the probe sonicator. A 35 µL amount of the lipid preparation was warmed to 37 °C and deposited onto freshly cleaved mica surfaces
Microfluidic anodization of aluminum films for the fabrication of nanoporous lipid bilayer support structures
Beilstein J. Nanotechnol. 2011, 2, 104–109, doi:10.3762/bjnano.2.12
- . First, 5 mL of a lipid chloroform solution (5 mg/mL) were vacuum dried in a glass vessel. Then, a phosphate buffered saline (5 mL, 0.9% NaCl, 100 mM phosphate buffer, pH 7.2) was added to form multilamelar vesicles. Sonication and extrusion (Avanti Polar Lipids, U.S.A.) were performed to produce
- unilamellar small vesicles of approximate sizes between 60 and 80 nm as determined by dynamic light scattering (Dynapro, Wyatt Technology Corporation, U.S.A.). The vesicle solution was then injected into the microfluidic channel for the synthesis of the lipid bilayer on the modified alumina membrane. The
- impedance obtained before and after application of lipid vesicles to the front side of the silanized nanoporous membrane. The impedance measured at 10 Hz across the membrane increased by more than five orders of magnitude after vesicle application. We attribute this effect to the formation of a lipid
Review and outlook: from single nanoparticles to self-assembled monolayers and granular GMR sensors
Beilstein J. Nanotechnol. 2010, 1, 75–93, doi:10.3762/bjnano.1.10
- understood. Recent studies indicate specific genes and proteins play a major role [22]. As shown in Figure 5, the growth dynamic is believed to be a multistep process [22][23]: Invagination of cytoplasmic membrane: The cytoplasmic membrane invaginates for vesicle formation. These vesicles later serve as
- within the vesicles is controlled by an oxidation–reduction system. Nucleation: Several proteins are believed to regulate the morphology. Mms5, Mms6, Mms7 and Mm13 are tightly bound to the magnetic nanoparticle. All these proteins are amphiphilic. Their N-terminal is hydrophilic while their C-terminal is
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