Toxicity and safety study of silver and gold nanoparticles functionalized with cysteine and glutathione

• Barbara Pem,
• Igor M. Pongrac,
• Lea Ulm,
• Ivan Pavičić,
• Valerije Vrček,
• Darija Domazet Jurašin,
• Marija Ljubojević,
• Adela Krivohlavek and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2019, 10, 1802–1817, doi:10.3762/bjnano.10.175

• studies indicating that AgNPs negatively impact cell membranes, interfere with signaling pathways, disrupt the cell cycle, and cause mitochondrial dysfunction, oxidative stress, DNA damage and apoptosis [7][8][9]. Many reports on AgNP toxicity attribute it fully or partially to dissolved or released ionic

• reduces or increases their safety. For this purpose, the efficiency of NP uptake, cell viability, apoptosis induction, oxidative stress response and genotoxicity parameters of L929 cells treated with prepared NPs were determined and compared with control cells. A range of NP concentrations were tested for

• significant number of late apoptotic cells, while CYS- and GSH-coated AgNPs were shown to be safer than expected. In both cases, more than 88% of fibroblasts survived the treatment with the highest dose applied (10 mg Ag L−1). As the exposure to NPs is known to induce oxidative stress in cells [75][76], ROS

Lipid nanostructures for antioxidant delivery: a comparative preformulation study

• Elisabetta Esposito,
• Maddalena Sguizzato,
• Markus Drechsler,
• Paolo Mariani,
• Federica Carducci,
• Claudio Nastruzzi,
• Giuseppe Valacchi and
• Rita Cortesi

Beilstein J. Nanotechnol. 2019, 10, 1789–1801, doi:10.3762/bjnano.10.174

• retinoic acid, have been shown to improve skin condition and even counteract the effects of exogenous stress factors such as smoking on skin aging. This work describes the design and development of lipid nanoparticles containing antioxidant agents (α-tocopherol or retinoic acid) to protect human skin

• nanostructured lipid carriers compositions. Human skin explants were treated with α-tocopherol-loaded nanostructured lipid carriers and then exposed to cigarette smoke, and the protein levels of the stress-induced enzyme heme oxygenase were analyzed in skin homogenates. Interestingly, it was found that

• oxidative stress [7]. The release of reactive oxygen species from tobacco smoke provokes a series of systemic immunomodulatory effects that leads to a compromised inflammatory response. These destructive mechanisms also affect collagen synthesis and the skin cellular reparative effects [8][9]. It has been

The impact of crystal size and temperature on the adsorption-induced flexibility of the Zr-based metal–organic framework DUT-98

• Simon Krause,
• Volodymyr Bon,
• Hongchu Du,
• Rafal E. Dunin-Borkowski,
• Ulrich Stoeck,
• Irena Senkovska and
• Stefan Kaskel

Beilstein J. Nanotechnol. 2019, 10, 1737–1744, doi:10.3762/bjnano.10.169

• fragmentation along the pore channels, which run along the rods and crystallographic b-axis in DUT-98cp. Thus, bond cleavage upon fragmentation is expected to occur at the edges of the SBB in DUT-98, which runs in parallel to the pore channels. This fragmentation is likely caused by the stress upon structural

Subsurface imaging of flexible circuits via contact resonance atomic force microscopy

• Wenting Wang,
• Chengfu Ma,
• Yuhang Chen,
• Lei Zheng,
• Huarong Liu and
• Jiaru Chu

Beilstein J. Nanotechnol. 2019, 10, 1636–1647, doi:10.3762/bjnano.10.159

• been carried out using CR-AFM for subsurface imaging, its application in defect diagnosis for flexible circuits has seldom been reported. Intuitively, the presence of buried metal circuit patterns in the tip-generated stress field will alter the local indentation modulus. This consequently leads to

• convenient modeling of the contact mechanics for multilayers without the requirement of a rigid substrate. In their approach, the stress and displacement fields for each layer and the substrate are first expressed in terms of harmonic Papkovich–Neuber potentials. Then, the unknown functions in the potential

• formulas are determined from the boundary conditions at the surface and at the interface between adjacent layers. Perfect bonding and free sliding are assumed for the layer-to-layer contact, which transmit displacement and stress from one layer to the next. Considering a frictionless contact between the

Graphynes: an alternative lightweight solution for shock protection

• Kang Xia,
• Haifei Zhan,
• Aimin Ji,
• Jianli Shao,
• Yuantong Gu and
• Zhiyong Li

Beilstein J. Nanotechnol. 2019, 10, 1588–1595, doi:10.3762/bjnano.10.154

• propagation of cracks. Tracking the atomic von Mises stress distribution, it is found that its cumulative density function has a strong correlation with the magnitude of the Young’s modulus of the GYs. For nanosheets with a higher Young’s modulus, it tends to transfer momentum at a faster rate. Thus, a better

• : graphyne; in silico studies; stress wave propagation; supersonic-velocity impact; Introduction Owing to its versatile flexibility, carbon is able to form three different hybridization states namely sp, sp2 and sp3, which yields many kinds of carbon allotropes. Graphite and diamond are the two common

• ballistic protection [27]. Utilizing MD methods, a study suggests that the impact resistance of graphene is strongly correlated with the density of monovacancies [28]. Our recent work reveals the transmission of stress waves would eventually influence the penetration energy and crack growth in graphene [29

Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices

• Giulia Lo Dico,
• Bernd Wicklein,
• Lorenzo Lisuzzo,
• Giuseppe Lazzara,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2019, 10, 1303–1315, doi:10.3762/bjnano.10.129

• properties of the bionanocomposite materials were evaluated in stress–strain measurements (Figure S5, Supporting Information File 1), analysing the influence of the nanofiller content on the elastic behaviour as it has been described in related biopolymer-based nanocomposites [26]. The results show that the

Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping

• Lukas Grünewald,
• Dagmar Gerthsen and
• Simon Hettler

Beilstein J. Nanotechnol. 2019, 10, 1290–1302, doi:10.3762/bjnano.10.128

• phase masks Fabrication of SixNy membranes and aC film deposition A 200 µm thick Si wafer with 120 nm thick low-stress SixNy coating on both sides was used as base material. Optical lithography and etching methods for SixNy and Si were applied to produce free-standing SixNy thin films (Figure 1

Alloyed Pt₃M (M = Co, Ni) nanoparticles supported on S- and N-doped carbon nanotubes for the oxygen reduction reaction

• Stéphane Louisia,
• Yohann R. J. Thomas,
• Pierre Lecante,
• Marie Heitzmann,
• M. Rosa Axet,
• Pierre-André Jacques and
• Philippe Serp

Beilstein J. Nanotechnol. 2019, 10, 1251–1269, doi:10.3762/bjnano.10.125

• performance has been aged following a recommended accelerated stress test (AST) cycle for catalyst support corrosion. Results and Discussion Synthesis and characterization of the CNTs and Pt3M/CNT Three kinds of CNTs have been produced by catalytic chemical vapor deposition (c-CVD): undoped (CNTs), N-doped (N

• and accelerated stress tests First, the washed catalysts Pt3Co/N-CNT, Pt3Co/N-CNTHT and Pt3Ni/N-CNTHT were integrated into the MEA with a platinum loading of 0.26, 0.24 and 0.3 mgPt/cm2, respectively. A reference MEA, integrating the commercial reference catalyst Pt3Co/CB with a loading of 0.3 mgPt·cm

Quantitative analysis of annealing-induced instabilities of photo-leakage current and negative-bias-illumination-stress in a-InGaZnO thin-film transistors

• Dapeng Wang and
• Mamoru Furuta

Beilstein J. Nanotechnol. 2019, 10, 1125–1130, doi:10.3762/bjnano.10.112

• . The hysteresis after negative-bias-illumination-stress (NBIS) is quantitatively investigated by using the double-scan mode and a positive gate pulse. Despite the abnormal transfer properties in the low-temperature-treated device, the excited holes are identically trapped at the front interface

• the backlight for non-emissive displays. The degradation of oxide-based TFTs under this kind of negative-bias-illumination-stress (NBIS) is a key issue that has been investigated over the last decade [6][7]. Despite all efforts to unveil the mechanisms of NBIS, such as first-principles calculations

• measurement over a period of 104 s (Figure 3). In the forward measurement (Figure 3a–c), the initial transfer curve of the TFT treated at 300 °C exhibits a serious SS deterioration. The extent of SS degradation is gradually aggravated along with on-current reduction with the increasing stress duration. The

Synthesis and characterization of quaternary La(Sr)S–TaS₂ misfit-layered nanotubes

• Marco Serra,
• Erumpukuthickal Ashokkumar Anumol,
• Dalit Stolovas,
• Iddo Pinkas,
• Ernesto Joselevich,
• Reshef Tenne,
• Andrey Enyashin and
• Francis Leonard Deepak

Beilstein J. Nanotechnol. 2019, 10, 1112–1124, doi:10.3762/bjnano.10.111

• Ry. All calculations were performed using variable-cell and atomic position relaxations, with convergence criteria corresponding to the maximum residual stress of 0.1 GPa for each component of the stress tensor, and the maximum residual force component of 0.05 eV/Å. Preliminary test calculations of

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• . In conclusion, the high cellular uptake and the antioxidant properties associated with the phenolic moieties in the modified particles allow for a potential application in biomedical areas. Keywords: antioxidants; chitosan; maghemite nanoparticles; oxidative stress; phenolic compound; Introduction

• stress, inflammation, aging in general, and the development of fatal diseases, such as cancer, neurodegenerative disorders, atherosclerosis, heart failure, myocardial infarction, and infections. ROS of radical origin (superoxide and hydroxyl) are particularly harmful because they initiate oxidative chain

• induce oxidative stress in living organisms via the Fenton reaction. Therefore, it is crucially important in biological applications of iron oxide nanoparticles to counteract this undesirable effect by antioxidants. The combination of magnetic targetability with antioxidant properties is an interesting

Effects of gold and PCL- or PLLA-coated silica nanoparticles on brain endothelial cells and the blood–brain barrier

• Aniela Bittner,
• Angélique D. Ducray,
• Hans Rudolf Widmer,
• Michael H. Stoffel and
• Meike Mevissen

Beilstein J. Nanotechnol. 2019, 10, 941–954, doi:10.3762/bjnano.10.95

• and lysosomes in microglia [10]. None of the NPs investigated resulted in cytotoxicity, decreased cell viability, apoptosis, autophagy or inflammation. However, exposure to NPs led to oxidative stress via depletion of cellular glutathione and to a downregulation of neuronal differentiation markers in

• , oxidative stress and an increase in inflammatory cytokines in dopaminergic neuron-like cells. In vivo intranasal administration of these NPs corroborated these findings and showed localization of Si-NPs mainly in the striatum and hippocampus [13]. As LTS finds its application in vessels of the brain, the

• cytotoxicity in HUVECs. Furthermore, Si-NPs were shown to induce oxidative stress and inflammation mediated by mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) [21] pathways that are related to cell proliferation and differentiation but also to

The systemic effect of PEG-nGO-induced oxidative stress in vivo in a rodent model

• Qura Tul Ain,
• Samina Hyder Haq,
• Abeer Alshammari,
• Moudhi Abdullah Al-Mutlaq and
• Muhammad Naeem Anjum

Beilstein J. Nanotechnol. 2019, 10, 901–911, doi:10.3762/bjnano.10.91

• , Kingdom of Saudi Arabia 10.3762/bjnano.10.91 Abstract Oxidative stress (OS) plays an important role in the pathology of certain human diseases. Scientists have developed great interest regarding the determination of oxidative stress caused after the administration of nano-graphene composites (PEG-nGO

• polyethylene glycol (PEG). PEGylation of nGO was confirmed by Fourier-transform infrared spectroscopy (FTIR), UV spectroscopy and TEM. The average size distribution of nGO and PEG-nGO was determined by using dynamic light scattering (DLS). Subsequently, an in vivo study measuring a marker for oxidative stress

• increased OS even after 4 h. In conclusion increased OS induced by PEG-nGO could be detrimental to brain, heart and kidneys. Keywords: nano-graphene oxide; nanomedicine; oxidative stress; PEGylation; Introduction The recent progress in nanoscience and nanotechnology that has facilitated the synthesis of

Novel reversibly switchable wettability of superhydrophobic–superhydrophilic surfaces induced by charge injection and heating

• Xiangdong Ye,
• Junwen Hou and
• Dongbao Cai

Beilstein J. Nanotechnol. 2019, 10, 840–847, doi:10.3762/bjnano.10.84

• termed electrowetting [19]. The equilibrium morphology under electrical wetting conditions is determined by the equilibrium of Maxwell stress and Laplace pressure [20][21]. Verplanck et al. [22] reported the reversible electrical wetting of droplets on superhydrophobic silicon nanowires in air and oil

Towards rare-earth-free white light-emitting diode devices based on the combination of dicyanomethylene and pyranine as organic dyes supported on zinc single-layered hydroxide

• Jeff L. Nyalosaso,
• Rachod Boonsin,
• Pierre Vialat,
• Damien Boyer,
• Geneviève Chadeyron,
• Rachid Mahiou and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2019, 10, 760–770, doi:10.3762/bjnano.10.75

• supply comes from China, which also has the largest demand for REEs at 65% of the total demand, even before the United States (15%). In 2010, China announced a 40% reduction in exports of REEs as it wants to reduce stress on its REE reserves. This led to a 600% price increase [6]. Moreover, the cost of a

Outstanding chain-extension effect and high UV resistance of polybutylene succinate containing amino-acid-modified layered double hydroxides

• Adam A. Marek,
• Vincent Verney,
• Christine Taviot-Gueho,
• Grazia Totaro,
• Laura Sisti,
• Annamaria Celli and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2019, 10, 684–695, doi:10.3762/bjnano.10.68

• sweeps from 0.1 to 100 rad s−1 and the gap between plates set at 1 mm. In all cases, the oscillatory shear stress amplitude was checked to ensure that measurements were performed inside the linear viscoelastic domain. The storage modulus (G’), loss modulus (G”) and tan δ (ratio of G” and G’) were

Mechanical and thermodynamic properties of Aβ₄₂, Aβ₄₀, and α-synuclein fibrils: a coarse-grained method to complement experimental studies

• Adolfo B. Poma,
• Horacio V. Guzman,
• Mai Suan Li and
• Panagiotis E. Theodorakis

Beilstein J. Nanotechnol. 2019, 10, 500–513, doi:10.3762/bjnano.10.51

• coefficient n in the indentation curves measuring the force as a function of hn. We found n = 3/2 in the linear regime, which corresponds to the Hertzian theory [12]. Tensile deformation The experimental calculation of the stress–strain data at the nanoscale can be done by using optical tweezers (OT) [50

• tensile deformation, the fibril stretches from a reference length (L0) to L, and the strain is given by . The stress is defined by the total force acting on the springs ktop divided by the cross-sectional area, A, of the sample. This area is calculated as follows [53]: For a given set of Cartesian points

• , it determines the smallest convex polygon containing all the given points. Then, we monitor the elementary area of this polygon during the simulation [54]. From the stress–strain plot one can derive the corresponding tensile Young’s modulus, YL. Shear deformation The experimental techniques employed

Wearable, stable, highly sensitive hydrogel–graphene strain sensors

• Jian Lv,
• Chuncai Kong,
• Chao Yang,
• Lu Yin,
• Itthipon Jeerapan,
• Fangzhao Pu,
• Xiaojing Zhang,
• Sen Yang and
• Zhimao Yang

Beilstein J. Nanotechnol. 2019, 10, 475–480, doi:10.3762/bjnano.10.47

• the uniaxial tensile strain–stress curves of the hydrogels fabricated with (WG-hydrogel) and without glycerol (W-hydrogel). Under the same strain, the WG-hydrogel shows less stress in the two strain–stress curves, indicating that including the glycerol provides the hydrogel with higher softness, thus

• making it more adaptable to external force. The complete yield strain–stress curves of the two hydrogels is shown in Supporting Information File 1, Figure S1, in which the fracture strain of the W-hydrogel is around 800% with a stress of 0.03 MPa, while the introduction of glycerol increases the break

• stress to 0.06 MPa at a strain of 2000%. The difference between the two hydrogels in the compressing strain–stress curve is not much as that in tensile mode, as shown in Figure 2b. An image of the synthesized graphene–hydrogel electrode is shown in Figure 2c. A uniform film is formed on the surface of

Gold nanoparticles embedded in a polymer as a 3D-printable dichroic nanocomposite material

• Lars Kool,
• Anton Bunschoten,
• Aldrik H. Velders and
• Vittorio Saggiomo

Beilstein J. Nanotechnol. 2019, 10, 442–447, doi:10.3762/bjnano.10.43

• operating at 120 kV. The mean aspect ratio of the AuNPs was calculated by measuring approximately 800 particles from 24 micrographs. A TE instruments DMA Q800 instrument was used for the mechanical analysis of the plastics using the stress/strain program with a force ramp rate of 1 N/min at isothermal (25

• °C) temperature. Four samples of the pure PVA and four samples of the AuNP–PVA materials were tested, where each sample was also flipped upside down and the stress/strain was recorded again. The average of the measurements was used in Figure 2c with the standard deviation shown as the error bar

Advanced scanning probe lithography using anatase-to-rutile transition to create localized TiO₂ nanorods

• Julian Kalb,
• Vanessa Knittel and
• Lukas Schmidt-Mende

Beilstein J. Nanotechnol. 2019, 10, 412–418, doi:10.3762/bjnano.10.40

• , the breaking line in Figure 3B is marked purple. The breaking line was induced by mechanical stress generated by scratching the sample with a diamond writer manually. The mechanical stress was guided through the sample from the center of the scratch to surrounding regions. The film was removed close

• Figure 2. For clarity, nanorods are colored bluish and the scarified surface is colored yellowish. B) SEM image after applying several times the hydrothermal growth to a stress-induced line of breakage. For clarity, the breaking line is colored purple. The breaking line does not specifically promote the

Intuitive human interface to a scanning tunnelling microscope: observation of parity oscillations for a single atomic chain

• Sumit Tewari,
• Jacob Bakermans,
• Christian Wagner,
• Federica Galli and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2019, 10, 337–348, doi:10.3762/bjnano.10.33

• annealing cycles to obtain an atomically flat Au(111) facet showing herringbone surface reconstruction. We further prepare the surface at low temperature by creating a localized stress pattern [11][12][13][14] on the surface using gentle indentation of the STM tip at a spot on the surface remote from the

• ) surface with herringbone reconstruction and straight step edges in crystallographic directions (i.e., , and ) prepared by stress-induced lattice deformations at low temperatures, (b) Gold adatoms deposited on a Au(111) surface from the STM tip. Images obtained at about 3 K after the temperature was

Heating ability of magnetic nanoparticles with cubic and combined anisotropy

• Nikolai A. Usov,
• Mikhail S. Nesmeyanov,
• Elizaveta M. Gubanova and
• Natalia B. Epshtein

Beilstein J. Nanotechnol. 2019, 10, 305–314, doi:10.3762/bjnano.10.29

• nanoparticles in biological media to quantitatively predict their heating efficiency in magnetic nanoparticle hyperthermia. In this respect we would like to stress that the behavior of an assembly of magnetic nanoparticles in viscous liquids and biological media is different [2][3]. It has been proved recently

Study of silica-based intrinsically emitting nanoparticles produced by an excimer laser

• Imène Reghioua,
• Mattia Fanetti,
• Sylvain Girard,
• Diego Di Francesca,
• Simonpietro Agnello,
• Layla Martin-Samos,
• Marco Cannas,
• Matjaz Valant,
• Melanie Raine,
• Marc Gaillardin,
• Nicolas Richard,
• Philippe Paillet,
• Aziz Boukenter,
• Youcef Ouerdane and
• Antonino Alessi

Beilstein J. Nanotechnol. 2019, 10, 211–221, doi:10.3762/bjnano.10.19

• mass and possible increase of the induced thermal gradient, which together can create stress or inhomogeneity and can induce explosion, implies a higher tendency to explosion. Furthermore, the laser spot has a spatial profile (typically with a maximum in the center) which implies that different regions

Wet chemistry route for the decoration of carbon nanotubes with iron oxide nanoparticles for gas sensing

• Hussam M. Elnabawy,
• Juan Casanova-Chafer,
• Badawi Anis,
• Mostafa Fedawy,
• Mattia Scardamaglia,
• Carla Bittencourt,
• Ahmed S. G. Khalil,
• Eduard Llobet and
• Xavier Vilanova

Beilstein J. Nanotechnol. 2019, 10, 105–118, doi:10.3762/bjnano.10.10

• conditions. As research studies show, exposure to this gas can lead to an increase in oxidative stress in the body, resulting in behavioral and learning-memory impairments. Also, there is a consistent relationship between NO2 and respiratory and asthmatic problems at mean daily concentrations (20–80 ppb

Pull-off and friction forces of micropatterned elastomers on soft substrates: the effects of pattern length scale and stiffness

• Peter van Assenbergh,
• Marike Fokker,
• Julian Langowski,
• Jan van Esch,
• Marleen Kamperman and
• Dimitra Dodou

Beilstein J. Nanotechnol. 2019, 10, 79–94, doi:10.3762/bjnano.10.8

• - and/or nanoscale fibrillar geometries have been reported [7], where the flexibility of the individual fibrils leads to a low Eeff [8]. Furthermore, micropatterns with a fibrillar geometry have been shown to have better defect control [9] and better stress distribution [10] compared to smooth adhesives

• material is used for the micropattern, the Eeff is low, leading to better defect control, stress distribution, and contact stiffness compared to micropatterns made of stiffer materials [22]. Also, the strength of the contacts formed between the adhesive and the substrate is affected by the material

• and PVA-18 normalized by the sample area (i.e., pull-off stress), for samples of PDMS-580 with various geometries and feature sizes. The results for the samples made of PDMS-280 are not shown here, as these exhibited similar trends to the PDMS-580 samples. Measurement data of PDMS-280 micropatterns