Intake of silica nanoparticles by giant lipid vesicles: influence of particle size and thermodynamic membrane state

• Florian G. Strobl,
• Florian Seitz,
• Christoph Westerhausen,
• Armin Reller,
• Adriano A. Torrano,
• Christoph Bräuchle,
• Achim Wixforth and
• Matthias F. Schneider

Beilstein J. Nanotechnol. 2014, 5, 2468–2478, doi:10.3762/bjnano.5.256

• possessing such a machinery [13]. This indicates that endocytosis-like particle uptake can be driven by physical interactions between cargo and cell membrane. The investigation of simplified model systems thus offers a possibility for an understanding of these processes on a theoretical physical base. In

• interactions and possible thermodynamic changes of the lipid membrane, which can result in drastic alterations of its physical properties (e.g., bending stiffness, permeability and spontaneous curvature). Even though the model system that was investigated here is quite distinct from a real cell membrane we

• −20 mV for HeLa cells and −30 mV for red blood cells were measured [49]. The dotted curve in Figure 4 shows the expected electrostatic force between a cationic particle with ζ = +30 mV and a cell membrane with ζ = −30 mV in a medium with an ionic strength of I = 160 mM. The physical forces in this

Proinflammatory and cytotoxic response to nanoparticles in precision-cut lung slices

• Stephanie Hirn,
• Nadine Haberl,
• Kateryna Loza,
• Matthias Epple,
• Wolfgang G. Kreyling,
• Barbara Rothen-Rutishauser,
• Markus Rehberg and
• Fritz Krombach

Beilstein J. Nanotechnol. 2014, 5, 2440–2449, doi:10.3762/bjnano.5.253

• staining, and WST-1 assay. As LDH is present in the cytoplasm of cells, detection of LDH in the culture medium of PCLS indicates a loss of cell membrane integrity. Therefore, LDH release is a direct measure of a cytotoxic response or an indirect measure of cell viability. As displayed in Figure 1, the LDH

Nanoparticle interactions with live cells: Quantitative fluorescence microscopy of nanoparticle size effects

• Li Shang,
• Karin Nienhaus,
• Xiue Jiang,
• Linxiao Yang,
• Katharina Landfester,
• Volker Mailänder,
• Thomas Simmet and
• G. Ulrich Nienhaus

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

• internalization machinery involved, different endocytic mechanisms are utilized. Most cells are capable of pinocytosis (drinking by cells), in which particles of up to several hundred nanometers can be internalized [11]. In this process, an invagination forms in the cell membrane. Typically, the inward budding

Nanobioarchitectures based on chlorophyll photopigment, artificial lipid bilayers and carbon nanotubes

• Marcela Elisabeta Barbinta-Patrascu,
• Stefan Marian Iordache,
• Ana Maria Iordache,
• Nicoleta Badea and
• Camelia Ungureanu

Beilstein J. Nanotechnol. 2014, 5, 2316–2325, doi:10.3762/bjnano.5.240

• . [49] pointed out that cell membrane damage resulting from direct contact with carbon nanotubes is the most plausible mechanism leading to bacterial cell death. Our results showed that small amounts of SWCNTs were enough to achieve high antimicrobial potency (see samples V3 and V4). The cholesterol

Coating with luminal gut-constituents alters adherence of nanoparticles to intestinal epithelial cells

• Heike Sinnecker,
• Katrin Ramaker and
• Andreas Frey

Beilstein J. Nanotechnol. 2014, 5, 2308–2315, doi:10.3762/bjnano.5.239

• – directly on the cell membrane. This interaction-type can be abolished by treating the particles with proteins (“passivation” of particle surface). Coating of particles with constituents of the intestinal fluid, on the other hand, may result in more complex attachment mechanisms. The intestinal fluid is a

Imaging the intracellular degradation of biodegradable polymer nanoparticles

• Anne-Kathrin Barthel,
• Martin Dass,
• Melanie Dröge,
• Jens-Michael Cramer,
• Daniela Baumann,
• Markus Urban,
• Katharina Landfester,
• Volker Mailänder and
• Ingo Lieberwirth

Beilstein J. Nanotechnol. 2014, 5, 1905–1917, doi:10.3762/bjnano.5.201

• the cell membrane are recognized by the overlay of red- and green-stained regions (cell membrane and PLLA nanoparticles, respectively) and are displayed as yellow pixels in the CLSM overlay images. However, there are no prominent attachments of the particles to the cellular membrane and only rarely

• showing the relative fluorescence intensity of the cells for different residence times. CLSM images of cells treated with PLLA/magnetite particles; incubation time: 24 h; pictures taken at specified times after particle addition: A) 24 h, B) 48 h, C) 72 h, D) 5 d, E) 7 d, and F) 14 days. Red: cell

• membrane; Green: PLLA nanoparticles. TEM bright field micrographs of a dispersion of magnetite-decorated PLLA nanoparticles prepared by drop casting and subsequent carbon evaporation (A) and by high pressure freezing (HPF) followed by freeze substitution and microtomy (B). The inset of B shows the

Carbon-based smart nanomaterials in biomedicine and neuroengineering

• Antonina M. Monaco and
• Michele Giugliano

Beilstein J. Nanotechnol. 2014, 5, 1849–1863, doi:10.3762/bjnano.5.196

• the spontaneous extracellular electrical activity in a murine neuronal cell line, which yielded results in good agreement with recordings made by means of conventional MEAs (Figure 5). Single-spin NV-NDs embedded in an artificial lipid bilayer [136] and in a real cell membrane, in which there is a

Influence of surface-modified maghemite nanoparticles on in vitro survival of human stem cells

• Michal Babič,
• Daniel Horák,
• Lyubov L. Lukash,
• Tetiana A. Ruban,
• Yurii N. Kolomiets,
• Svitlana P. Shpylova and
• Oksana A. Grypych

Beilstein J. Nanotechnol. 2014, 5, 1732–1737, doi:10.3762/bjnano.5.183

• cellular uptake of the magnetic nanoparticles and enhance their specific targeting effect, surface functionalization has to be employed to coat the nanoparticle surface with ligands that could specifically interact with the receptors overexpressed in the cell membrane. While the size of the dry

In vitro and in vivo interactions of selected nanoparticles with rodent serum proteins and their consequences in biokinetics

• Wolfgang G. Kreyling,
• Stefanie Fertsch-Gapp,
• Martin Schäffler,
• Blair D. Johnston,
• Nadine Haberl,
• Christian Pfeiffer,
• Jörg Diendorf,
• Carsten Schleh,
• Stephanie Hirn,
• Manuela Semmler-Behnke,
• Matthias Epple and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1699–1711, doi:10.3762/bjnano.5.180

• twenty-four hours the viability of the PCLS was tested by lactate dehydrogenase (LDH) analysis for cell membrane damage and a WST-1 assay for mitochondrial activity in the cell culture supernatant as well as the release of the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin

• increased in PCLS from rats treated with six-month old, 250 µg AgNP. But this increase was not statistically significant. This indicates that dissolved/dissociated Ag species which had been released from AgNP damaged the cell membrane of PCLS more than the Ag+ ions from silver acetate. However

Different endocytotic uptake mechanisms for nanoparticles in epithelial cells and macrophages

• Dagmar A. Kuhn,
• Dimitri Vanhecke,
• Benjamin Michen,
• Fabian Blank,
• Peter Gehr,
• Alke Petri-Fink and
• Barbara Rothen-Rutishauser

Beilstein J. Nanotechnol. 2014, 5, 1625–1636, doi:10.3762/bjnano.5.174

• interaction of the responsible receptors on the cell surface and the ligands. Macropinocytosis, which is also actin-driven, forms protrusions at the outer cell membrane which then again fuse with the cell membrane by taking up larger fragments or debris [14]. Clathrin-mediated endocytosis is very well studied

• consisting of transmembrane receptors and cytosolic proteins, such as clathrin and the AP2 adaptor complex [20]. On the other hand, caveolin-mediated endocytosis is responsible for the homeostasis of cholesterol [20]. The static structures of caveolae form flask-shaped invaginations in the cell membrane

• , fluorescently labelled transferrin can be used to investigate clathrin-mediated endocytosis [32][41][42]. Caveolae and lipid raft internalizations are known to be inhibited by nystatin, filipin and methyl-β-cyclodextrin (mβcd) through depletion of the cholesterol from the cell membrane by forming inclusion

Precise quantification of silica and ceria nanoparticle uptake revealed by 3D fluorescence microscopy

• Adriano A. Torrano and
• Christoph Bräuchle

Beilstein J. Nanotechnol. 2014, 5, 1616–1624, doi:10.3762/bjnano.5.173

• microscopy. One emission channel is reserved for the plasma membrane and the other one for the nanoparticles. This means that cell membrane and particles must be fluorescently labeled with spectrally separable markers. The two image stacks acquired can then be processed by Particle_in_Cell-3D. Once the

• an enlarged transition region between extra- and intracellular spaces. It is much wider than the real cell membrane. The accuracy of the cell segmentation strategy and the typical thickness of the enlarged membrane region were studied by comparing the results achieved with Particle_in_Cell-3D with

• growth. Before addition to cells, the solution was vortexed for 10 s, treated in an ultrasonic bath for 10 min and vortexed again for 10 s. After the incubation time, and just before measurements, the cell membrane was stained with a solution of 10 µg·mL−1 wheat germ agglutinin, Alexa Fluor® 488 (Life

In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?

• Moritz Nazarenus,
• Qian Zhang,
• Mahmoud G. Soliman,
• Pablo del Pino,
• Beatriz Pelaz,
• Susana Carregal-Romero,
• Joanna Rejman,
• Barbara Rothen-Rutishauser,
• Martin J. D. Clift,
• Reinhard Zellner,
• G. Ulrich Nienhaus,
• James B. Delehanty,
• Igor L. Medintz and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1477–1490, doi:10.3762/bjnano.5.161

• which the goal is to deliver something to the cytosol. Getting stuck inside intracellular vesicles is redundant to the purpose of these applications. However, in contrast to endocytosis as described so far, studies exist in which it is claimed that NPs can directly translocate through the cell membrane

• kinetics [103]. Larger NPs (smaller than 60–70 nm) are internalized with lower kinetics to the extent that they are largely associated to the cell membrane over the time courses that see an intake of smaller NPS [62]. This has also been shown in fixed, permeabilized cells (to eliminate cell uptake

• fibers with high aspect ratios [100]. Flattening of NPs has been used, for example, to reduce NP uptake by cells in a way that flat NPs just adhere to the plasma cell membrane like a “backpack”, without being internalized, in contrast to spherical NPs that are readily incorporated [113][114]. Concerning

Protein-coated pH-responsive gold nanoparticles: Microwave-assisted synthesis and surface charge-dependent anticancer activity

• Dickson Joseph,
• Nisha Tyagi,
• Christian Geckeler and
• Kurt E.Geckeler

Beilstein J. Nanotechnol. 2014, 5, 1452–1462, doi:10.3762/bjnano.5.158

• and hence carried a negative surface charge. A recent report shows that gold nanospheres attached to a negatively charged cell surface penetrate the cell wall more easily, if they carry positive charges, because the cell membrane tries to restore its previous surface charge distribution by removing

Model systems for studying cell adhesion and biomimetic actin networks

• Dorothea Brüggemann,
• Johannes P. Frohnmayer and
• Joachim P. Spatz

Beilstein J. Nanotechnol. 2014, 5, 1193–1202, doi:10.3762/bjnano.5.131

• -binding protein, which binds to the cytoplasmic β tails of integrins, thus activating the molecule (Figure 1). When integrin is present in its activated state it shows a higher affinity for ligands on the extracellular side of the cell membrane [12][13][14][15]. Many of these protein ligands in the ECM

• , talin anchors the actin microfilament system to the cell membrane and promotes actin polymerisation. With these functions talin can also play a crucial role in the development of synthetic cells from lipid membranes. Reconstitution of talin into lipid membranes by self-assembly was first achieved by

Trade-offs in sensitivity and sampling depth in bimodal atomic force microscopy and comparison to the trimodal case

• Babak Eslami,
• Daniel Ebeling and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 1144–1151, doi:10.3762/bjnano.5.125

• addition to the noncontact forces. Figure 1 provides an example of single-mode attractive and repulsive images of a Nafion® fuel cell membrane (these images were acquired by using the standard amplitude modulation method [14]). A difference between the two images can be seen in terms of contrast inversion

Double layer effects in a model of proton discharge on charged electrodes

• Johannes Wiebe and
• Eckhard Spohr

Beilstein J. Nanotechnol. 2014, 5, 973–982, doi:10.3762/bjnano.5.111

• -dependent superposition of Eigen, H9O4+, and Zundel, H5O2+, cations. Multistate generalizations of this simple picture were later applied to a variety of physical, chemical and biological problems [24][25][26][27][28]. In order to utilize the methodology for highly acidic environments such as a fuel cell

• membrane, the approach was, on the other hand, extremely simplified towards a minimal two-state model, in which the proton is either attached to a single water molecule as a H3O+ ion or to two molecules as a H5O2+ ion [29][30]. The simple two-state EVB model was then combined with a very approximate and

Nanodiamond-DGEA peptide conjugates for enhanced delivery of doxorubicin to prostate cancer

• Amanee D Salaam,
• Patrick Hwang,
• Roberus McIntosh,
• Hadiyah N Green,
• Ho-Wook Jun and
• Derrick Dean

Beilstein J. Nanotechnol. 2014, 5, 937–945, doi:10.3762/bjnano.5.107

• size and zeta potential are particularly important for drug delivery applications as they give representations of size limitations and potential colloidal stability issues of a system. NDs permeate the cell membrane by endocytosis [20][36][37]. Through this pathway, NDs can effectively deliver drugs

Optimizing the synthesis of CdS/ZnS core/shell semiconductor nanocrystals for bioimaging applications

• Li-wei Liu,
• Si-yi Hu,
• Ying Pan,
• Jia-qi Zhang,
• Yue-shu Feng and
• Xi-he Zhang

Beilstein J. Nanotechnol. 2014, 5, 919–926, doi:10.3762/bjnano.5.105

• µg/mL. This experiment demonstrates the minimal cytotoxicity associated with these nanoparticle formulations. For the bioimaging study, it is well known the cell membrane folate receptor is a potential molecular target for tumor-selective drug delivery, and the folate conjugates can be used to target

Antimicrobial properties of CuO nanorods and multi-armed nanoparticles against B. anthracis vegetative cells and endospores

• Pratibha Pandey,
• Merwyn S. Packiyaraj,
• Himangini Nigam,
• Gauri S. Agarwal,
• Beer Singh and
• Manoj K. Patra

Beilstein J. Nanotechnol. 2014, 5, 789–800, doi:10.3762/bjnano.5.91

• [21]. Recently it has been found that conversion of three-dimensional polystyrene nanospheres to a two-dimensional nanodisc shape offers a larger contact surface with cell membranes and generates less impact during their interaction, which leads to a binding that is limited to the cell membrane with

• fraction in B. anthracis vegetative cell culture in most of the batches with the exception of few. The nanoparticles probably kill the cells by damaging the cell membrane mechanically, leading to leakage of cellular content. SEM observations discussed in later paragraphs support this probability. The broad

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

• Tatiana Borisova,
• Natalia Krisanova,
• Arsenii Borуsov,
• Roman Sivko,
• Ludmila Ostapchenko,
• Michal Babic and
• Daniel Horak

Beilstein J. Nanotechnol. 2014, 5, 778–788, doi:10.3762/bjnano.5.90

• away, the inner magnetization of nanoparticles disappears, and therefore their agglomeration, which carries the risk of embolization of the capillary vessels, can be avoided [3]. A key issue for enhancing of permeability of iron oxide nanoparticles through the cell membrane is the modification of their

Injection of ligand-free gold and silver nanoparticles into murine embryos does not impact pre-implantation development

• Ulrike Taylor,
• Wiebke Garrels,
• Annette Barchanski,
• Svea Peterson,
• Laszlo Sajti,
• Andrea Lucas-Hahn,
• Lisa Gamrad,
• Ulrich Baulain,
• Sabine Klein,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2014, 5, 677–688, doi:10.3762/bjnano.5.80

• pellucida and the cell membrane. Approximately 10 pL were then injected into the cytoplasm of one blastomere by using an Eppendorf transjector 5246 (Eppendorf, Hamburg, Germany), while the other blastomere was not treated [47]. This equals with regard to the AuNP and AgNP dispensions to approximately 1000

Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone

• Xiaohong Wang,
• Heinz C. Schröder and
• Werner E. G. Müller

Beilstein J. Nanotechnol. 2014, 5, 610–621, doi:10.3762/bjnano.5.72

• , is targeted in intact cell systems under certain physiological conditions to the cell membrane [36][37]. Among the phylogenetically oldest animals that have a skeleton based on calcium carbonate are the calcareous sponges with Sycon raphanus as an example (Figure 2A), the CA enzyme was cloned

• this enzyme is secreted by the sponge cells or bound to the cell membrane. The spicules from the calcareous sponges (Figure 2B), e.g., Sycon used in our studies [38][42], consists of almost pure calcium carbonate (calcite). In a first approach to investigate the formation of the calcareous spicules on

The softening of human bladder cancer cells happens at an early stage of the malignancy process

• Jorge R. Ramos,
• Joanna Pabijan,
• Ricardo Garcia and
• Malgorzata Lekka

Beilstein J. Nanotechnol. 2014, 5, 447–457, doi:10.3762/bjnano.5.52

• microtubules (MT) in AFM measurements remains open. Pelling et al. performed immunofluorescence and AFM studies in order to determine the influence of the MT on the cell membrane in response to serum conditions and nocodazole [17]. Their results show that the stiffness depends on the interplay between

• fluorescence images of the cell lines studied here, non-malignant HCV29 and the malignant cells HTB-9, HT-1376, and T24, respectively. The AFM error image (panels A, E, I, and M) enables to visualize the cell cytoskeleton that lies beneath the cell membrane. The filaments observed by AFM correspond to the

• actin filaments. Although, they are dispersed throughout the whole cell, they are mainly concentrated close to the cell membrane to form the so called actin-cortex. The AFM error image shows that these filaments are organized in two groups: (i) short actin filaments and (ii) and bundles of long acting

Electrospinning preparation and electrical and biological properties of ferrocene/poly(vinylpyrrolidone) composite nanofibers

• Ji-Hong Chai and
• Qing-Sheng Wu

Beilstein J. Nanotechnol. 2013, 4, 189–197, doi:10.3762/bjnano.4.19

• centre of the agar plate killed the bacteria over and around them (Figure 6b), which showed that the composite Fc/PVP nanofibers obviously inhibited growth of the E. coil. It can be explained that Fc is lipophilic in nature and able to pass through the cell membrane. When E. coli is in contact with Fc

Fabrication of multi-parametric platforms based on nanocone arrays for determination of cellular response

• Lindarti Purwaningsih,
• Tobias Schoen,
• Tobias Wolfram,
• Claudia Pacholski and
• Joachim P. Spatz

Beilstein J. Nanotechnol. 2011, 2, 545–551, doi:10.3762/bjnano.2.58

• of the substrate. The cell membrane and the cellular protrusions are in close proximity, which is important for the functional aspects of the substrates in possible applications as surfaces for neuro-active implants. Figure 3 shows the quantitative analysis of SHSY5Y-cell adhesion to three different