Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• within a raster consisting of up to 4096 × 3536 pixel2 as well as the time spent by the beam on each pixel (the so-called dwell time). According to our previous comparative study [31], a relatively small dose of Ga+ ions is sufficient for the required polymer transformation and we adopt here the same

Direct observation of oxygen-vacancy formation and structural changes in Bi₂WO₆ nanoflakes induced by electron irradiation

• Hong-long Shi,
• Bin Zou,
• Zi-an Li,
• Min-ting Luo and
• Wen-zhong Wang

Beilstein J. Nanotechnol. 2019, 10, 1434–1442, doi:10.3762/bjnano.10.141

• complex (inset of Figure 3b) consisting of two large nanoflakes each of ca. 140 nm in size, and the specimen was tilted along the [010] zone axis. In order to capture the transition state, the electron beam was spread out to match the large screen of the TEM to reduce the electron dose, and the exposure

Kelvin probe force microscopy of the nanoscale electrical surface potential barrier of metal/semiconductor interfaces in ambient atmosphere

• Petr Knotek,
• Tomáš Plecháček,
• Jan Smolík,
• Petr Kutálek,
• Filip Dvořák,
• Milan Vlček,
• Jiří Navrátil and
• Čestmír Drašar

Beilstein J. Nanotechnol. 2019, 10, 1401–1411, doi:10.3762/bjnano.10.138

• center of the irradiated area) with respect to the non-irradiated area of the Au layer (Figure 6). It should be noted, that the edges of the irradiated area are topographically elevated and exhibit a decreased surface potential because of the higher electron irradiation dose at the turning points of the

• e-beam. A higher dose led to a higher local temperature, which implies an increased formation of Au alloy and rims. The comparable so-called “Marangoni effect” was observed in laser-irradiated polymers as described by Lyutakov and co-workers [61]. The NIs formed on the thinnest Au (12 nm) exhibited

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

• objective lens are known problems. These effects are expected to only marginally affect the PM performance because of the almost parallel illumination of the PMs leading to a substantially reduced areal electron dose [17][21]. We have developed two different procedures to fabricate aC PMs in this work. The

• × 2048 pixels and a dwell time of 50 ns was used which results in a dose of around 0.2 ions/nm2. Phase-mask patterning In the case of BBs the required thickness profile (Equation 3) was milled with custom FIB routines. These are realized in the form of text files in which the spatial coordinates for the

Enhanced inhibition of influenza virus infection by peptide–noble-metal nanoparticle conjugates

• Zaid K. Alghrair,
• David G. Fernig and
• Bahram Ebrahimi

Beilstein J. Nanotechnol. 2019, 10, 1038–1047, doi:10.3762/bjnano.10.104

• was concentration-dependent (Figure 3). Counting plaques in multiple experiments allowed for the determination of the dose response and the IC50 values. In these experiments the IC50 value of the original FluPep sequence was found to be of the order of 140 pM (Figure 3, inset). This is less potent

• was due to one infective virus particle was met. Stability of gold nanoparticles to DTT ligand exchange. (A) UV–vis spectra of mixed-matrix-capped gold nanoparticles and mixed-matrix-capped gold nanoparticles incorporating 5% (mol/mol) FluPep ligand in PBS. Time- and dose-dependence of DTT ligand

• in PBS. Time and dose-dependence of DTT ligand exchange for (B) mixed-matrix silver nanoparticles and (C) silver nanoparticles incorporating different molar fractions of FluPep ligand. Results are the mean ± SD (n = 3). Purification of FluPep ligand-functionalised silver nanoparticles by CM-Sepharose

Serum type and concentration both affect the protein-corona composition of PLGA nanoparticles

• Katrin Partikel,
• Robin Korte,
• Dennis Mulac,
• Hans-Ulrich Humpf and
• Klaus Langer

Beilstein J. Nanotechnol. 2019, 10, 1002–1015, doi:10.3762/bjnano.10.101

• -affinity proteins, for example immunoglobulins, facilitate phagocytosis by cells of the mononuclear phagocyte system (MPS) [26]. Furthermore, one has to consider that the ratio between NP surface and protein concentration is closely related to the administration route and dose [27]. As a result

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

• inflammation and apoptosis via connection to the NF-κB pathway [22]. Size- and dose-dependent cytotoxicity and disruption of the BBB after exposure to SiO2 particles were shown in a human model and confirmed in vivo [23]. Integrity and function of the BBB of primary porcine brain microvascular ECs (PBECs) in

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

• , namely lipid peroxides, as well as antioxidant agents, including catalase, superoxide dismutase, glutathione, and glutathione S-transferase was conducted. A comparison at different intervals of time after the administration of a dose (5 mg/kg) of PEG-nGO was carried out. An increase in free radicals and

• the average size distribution of nGO and PEG-nGO, respectively. In vivo assays The number of free radicals produced by a dose of PEG-nGO was estimated by the comparative levels of lipid peroxides present in the control and treated groups. The level of lipid peroxides and free radical scavengers are

• Zhang and co-workers [29]. Biocompatibility of nGO was achieved by coating with polyethylene glycol (PEG). Then, a single dose (5 mg/kg) of synthesized PEG-nGO was administered to groups of groups of six mice. The dosage was found to be optimum in previous studies [28][29]. The animals were dissected

Polydopamine-coated Au nanorods for targeted fluorescent cell imaging and photothermal therapy

• Boris N. Khlebtsov,
• Andrey M. Burov,
• Timofey E. Pylaev and
• Nikolai G. Khlebtsov

Beilstein J. Nanotechnol. 2019, 10, 794–803, doi:10.3762/bjnano.10.79

• nonspecific uptake. To understand the safe dose of PEG-coated and folate-functionalized polydopamine-encapsulated AuNRs, we investigated their biocompatibility by a standard resazurin-based cytotoxic assay. Both folate-functionalized and PEG-coated nanocomposites incubated with HeLa cells during 24 and 48 h

• nanoparticles compared with PEG-coated particles. HeLa (F+) and HEK 293 (F−) cells were incubated with AuNR-PDA-R123-folate and AuNR-PDA-R123-PEG at a nanoparticle dose of 1010 mL−1 for 2 h. Fluorescent images of randomly selected cells under 488 nm light excitation were obtained using a Leica DM 2500

• ) dyes, coloring live cells in green and apoptotic cells in red (Figure 4B–D). To quantify the efficiency of treatment the cell viability was estimated by using the resazurin assay. After irradiation with the NIR laser for 200 s, HeLa cells treated with AuNR-PDA-R123-folate exhibited a dose-dependent

On the transformation of “zincone”-like into porous ZnO thin films from sub-saturated plasma enhanced atomic layer deposition

• Alberto Perrotta,
• Julian Pilz,
• Stefan Pachmajer,
• Antonella Milella and
• Anna Maria Coclite

Beilstein J. Nanotechnol. 2019, 10, 746–759, doi:10.3762/bjnano.10.74

• , development of controlled porosity, and formation and growth of ZnO crystallites. The layers developed controlled nanoporosity in the range of 1–5%, with pore sizes between 0.27 and 2.00 nm as measured with ellipsometric porosimetry (EP), as a function of the plasma dose and post-annealing temperature

• (GPC) as a function of the plasma dose time is reported in Figure 1a. The GPC was found to saturate at 1.6 Å/cycle, which is in line with the literature values for processes carried out at room temperature and the ones previously reported [40][57]. Plasma dose times below 6 s led to lower GPC, as

• reported as a function of the plasma dose. Two characteristics absorptions were identified. The stretching (ν) of hydroxyl (–OH) moieties was present in the spectra for all layers at wavenumbers in the range 3000–3600 cm−1. The νOH intensity was found to increase as a function of the plasma dose. This was

Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

• Marwa Mokni,
• Gianluigi Maggioni,
• Abdelkader Kahouli,
• Sara M. Carturan,
• Walter Raniero and
• Alain Sylvestre

Beilstein J. Nanotechnol. 2019, 10, 428–441, doi:10.3762/bjnano.10.42

• layer). The thickness of each single layer (either with or without Ag) was measured by RBS in monomeric units·cm−2. As highlighted in the Experimental section (see below), the parylene C amount deposited on the substrate (in monomeric units·cm−2) is directly obtained from the Cl RBS atomic dose, since

• corresponding Ag dose incorporated in these samples as a function of the number of rotations. If the samples B and C are neglected, one finds that the dose increases almost linearly as could be expected. Ag dose incorporated during a single rotation is 8.3 × 1015 atoms·cm−2. The reason of the anomalous behavior

• of samples B and C, the dose of which is higher than expected, is not completely clear, but it is thought to lie mainly in the very peculiar nature of the parylene deposition process, which is controlled by setting the pressure inside the chamber. This control method gives rise to hysteresis loops in

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

• deposited via resistive evaporation with a deposition rate of 3 Å/s. The Zeiss CrossBeam 1540XB FE SEM was employed for electron-beam exposure using an acceleration voltage of 10 kV, a current of 25 pA, a dose of 200 μAs/cm2, an area step size and dwell time of 1.6 nm and 200 ns, respectively, and an

Geometrical optimisation of core–shell nanowire arrays for enhanced absorption in thin crystalline silicon heterojunction solar cells

• Robin Vismara,
• Olindo Isabella,
• Andrea Ingenito,
• Fai Tong Si and
• Miro Zeman

Beilstein J. Nanotechnol. 2019, 10, 322–331, doi:10.3762/bjnano.10.31

• of SiOxFy particles, which start the formation of randomly distributed etch pits [42]. These regions become deeper during the process, thanks to the strong anisotropic nature of this RIE etching. A back-side emitter was formed by phosphorous ion implantation, with energy of 2 × 1015 cm−2 and dose of

Removal of toxic heavy metals from river water samples using a porous silica surface modified with a new β-ketoenolic host

• Said Tighadouini,
• Smaail Radi,
• Abderrahman Elidrissi,
• Khadija Haboubi,
• Maryse Bacquet,
• Stéphanie Degoutin,
• Mustapha Zaghrioui and
• Yann Garcia

Beilstein J. Nanotechnol. 2019, 10, 262–273, doi:10.3762/bjnano.10.25

• isotherm plots of SiG, SiNH2 and SiNL. Effect of pH on the adsorption of metal ions on SiNL, Adsorption dose: V = 10 mL, m = 10 mg of SiNL at optimum concentration (100 ppm in each case), t = 35 min and 25 °C, ∆qe = 0.3 (mg·g−1). (The optimum concentration means the initial concentration of metal ions

• required to reach a plateau shape). Effect of contact time on the adsorption capacity of Zn(II), Pb(II), Cd(II) and Cu(II) ions. Adsorption dose: V = 10 mL, m = 10 mg of SiNL at optimum concentration (100 ppm in each case), at pH 6 and 25 °C, ∆qe = 0.3 (mg·g−1). Pseudo-first-order and pseudo-second-order

• models fits for the adsorption of Zn(II), Pb(II), Cd(II) and Cu(II) ions by SiNL. Adsorption dose: V = 10 mL, m = 10 mg of SiNL using optimum pH (pH 6), optimum concentration (100 ppm in each case), and at 25 °C, ∆qe = 0.3 (mg·g−1). Effect of concentration on metal ion adsorption onto SiNL. Adsorption

Sputtering of silicon nanopowders by an argon cluster ion beam

• Xiaomei Zeng,
• Vasiliy Pelenovich,
• Zhenguo Wang,
• Wenbin Zuo,
• Sergey Belykh,
• Alexander Tolstogouzov,
• Dejun Fu and
• Xiangheng Xiao

Beilstein J. Nanotechnol. 2019, 10, 135–143, doi:10.3762/bjnano.10.13

• (CeFITec), Dept. de Física da Faculdade de Ciências e Tecnologia (FCT), Universidade Nova de Lisboa, Caparica, 2829-516, Portugal 10.3762/bjnano.10.13 Abstract In this work an Ar+ cluster ion beam with energy in the range of 10–70 keV and dose of 7.2 × 1014–2.3 × 1016 cluster/cm2 was used to irradiate

• pressed Si nanopowder targets consisting of particles with a mean diameter of 60 nm. The influence of the target density and the cluster ion beam parameters (energy and dose) on the sputtering depth and sputtering yield was studied. The sputtering yield was found to decrease with increasing dose and

• near 17 keV. The dose and energy dependence of the sputtering yield was explained by the competition of the finite size effect and the effect of debris formation. Keywords: finite size effect; gas cluster ion beam; silicon nanoparticles; smoothing effect; sputtering; Introduction Etching using gas

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

• particle size was not affected. Statistical analysis for the three samples shows that the average particle size of the NP does not increase when increasing the decoration dose. The mean particle size was found to be 3.44, 3.46 and 3.31 nm for decoration ratios of 1:1, 1:1.3 and 1:1.5, respectively (size

• ratio of 1:1 which is considered to be the optimum decoration ratio. By comparing these results to other results in the literature, we can conclude that there is an optimum decoration ratio which gives us the highest response, as the response increases with increasing decoration ratio dose until an

A comparison of tarsal morphology and traction force in the two burying beetles Nicrophorus nepalensis and Nicrophorus vespilloides (Coleoptera, Silphidae)

• Liesa Schnee,
• Benjamin Sampalla,
• Josef K. Müller and
• Oliver Betz

Beilstein J. Nanotechnol. 2019, 10, 47–61, doi:10.3762/bjnano.10.5

• local release might support shear-induced adhesion [46] and help to dose the secretion economically. In terms of the biological role, the higher attachment force in the pull direction might help the animals to climb effectively on a variety of structures such as plants and fur and might enable the males

Characterization and influence of hydroxyapatite nanopowders on living cells

• Przemyslaw Oberbek,
• Tomasz Bolek,
• Adrian Chlanda,
• Seishiro Hirano,
• Sylwia Kusnieruk,
• Julia Rogowska-Tylman,
• Ganna Nechyporenko,
• Viktor Zinchenko,
• Wojciech Swieszkowski and
• Tomasz Puzyn

Beilstein J. Nanotechnol. 2018, 9, 3079–3094, doi:10.3762/bjnano.9.286

• studied cells. CHO cells are the most sensitive to HAp particles, which is visible in the large viability differences between the samples treated low and high HAp concentrations. The effect strongly depends on the dose and the type of hydroxyapatite. For example, HAp F202 and GoHAP600s differ greatly in

• , densities, pH value, NOAA size and stoichiometry was scrutinized for a better understanding of the interactions between nanoscale hydroxyapatite and cells. The biological impact depends on dose and physicochemical properties of the HAp particles and the cell nature. Toxic effects occur only in the case of a

Size limits of magnetic-domain engineering in continuous in-plane exchange-bias prototype films

• Alexander Gaul,
• Daniel Emmrich,
• Timo Ueltzhöffer,
• Henning Huckfeldt,
• Hatice Doğanay,
• Johanna Hackl,
• Muhammad Imtiaz Khan,
• Daniel M. Gottlob,
• Gregor Hartmann,
• André Beyer,
• Dennis Holzinger,
• Slavomír Nemšák,
• Claus M. Schneider,
• Armin Gölzhäuser,
• Günter Reiss and
• Arno Ehresmann

Beilstein J. Nanotechnol. 2018, 9, 2968–2979, doi:10.3762/bjnano.9.276

• regions, see Appendix) and therefore smaller thermally stable domains. The limitations correlated to the patterning process when using shadow masks, however, cause spatial broadening of the ion dose gradient. Since the concerned regions correspond to the DW regions, there is a strong impact on the actual

• separate points. To do so, the ion beam was defocused, leading to a probe diameter of 8 nm. The resolution was determined by the knife-edge method from the image sharpness [46]. The ion dose was chosen to be 1 × 1015 ions·cm−2 to induce a maximum change of HEB [47]. A Raith Elphy multibeam pattern

• bombarded and non-bombarded regions individually. Here, γ ≈ 0.577 is the Euler constant, μ0 = 4π × 10−7 N·A−2 is the vacuum permeability, and tf is the thickness of the FM layer. The saturation magnetization Ms as a function of the ion dose was measured in [35] for a similar material system (Ms,NB = 1226

The nanoscaled metal-organic framework ICR-2 as a carrier of porphyrins for photodynamic therapy

• Jan Hynek,
• Sebastian Jurík,
• Martina Koncošová,
• Jaroslav Zelenka,
• Ivana Křížová,
• Tomáš Ruml,
• Kaplan Kirakci,
• Ivo Jakubec,
• František Kovanda,
• Kamil Lang and
• Jan Demel

Beilstein J. Nanotechnol. 2018, 9, 2960–2967, doi:10.3762/bjnano.9.275

• photobiological experiments were performed after 4 h of incubation with the nanoparticles. The cellular uptake upon incubation with different concentrations of the nanoparticles yielded almost linear dose dependence (Figure 6C). Furthermore, the intracellular localization of nanoICR-2/TPPPi(Ph) was investigated

• identical conditions (e.g., irradiation wavelength, time, dose). We can compare the activity of nanoICR-2/TPPPi(Ph) with the activity of previously studied PCN-222 nanoparticles where both systems display comparable activity [22]. Conclusion In the context of photodynamic therapy, we present composite

Hybrid Au@alendronate nanoparticles as dual chemo-photothermal agent for combined cancer treatment

• Anouchka Plan Sangnier,
• Romain Aufaure,
• Laurence Motte,
• Claire Wilhelm,
• Erwann Guenin and
• Yoann Lalatonne

Beilstein J. Nanotechnol. 2018, 9, 2947–2952, doi:10.3762/bjnano.9.273

• under irradiation within the first biological window (650–900 nm). The Au@alendronate nanoplatform thus provided a combined antitumor activity through drug delivery and photothermal therapy. Au@alendronate NPs inhibited in vitro the proliferation of prostate cancer cells (PC3) in a dose-dependent manner

• observed in absence or presence of laser irradiation. This could be related to the low dose of internalized gold NPs and indicates that the laser power is sufficiently low to avoid nonspecific biological damage. At extracellular concentrations of alendronate over 1 µM, cell viability was considerably

Charged particle single nanometre manufacturing

• Philip D. Prewett,
• Cornelis W. Hagen,
• Claudia Lenk,
• Steve Lenk,
• Marcus Kaestner,
• Tzvetan Ivanov,
• Ahmad Ahmad,
• Ivo W. Rangelow,
• Xiaoqing Shi,
• Stuart A. Boden,
• Alex P. G. Robinson,
• Dongxu Yang,
• Sangeetha Hari,
• Marijke Scotuzzi and
• Ejaz Huq

Beilstein J. Nanotechnol. 2018, 9, 2855–2882, doi:10.3762/bjnano.9.266

• : HM-01A using anisole solvent and HM-01C using chlorobenzene. The spin-coatability of the two formulations is shown in Figure 4a. Figure 5 shows 8 nm isolated lines written with a line dose of 0.08 nC·cm−1 in a 10 nm layer of HM-01A negative tone fullerene resist [41]. (Many novel resists require

• beam energy are shown in Figure 7 for dense features [41]. Figure 7a shows dense single-pixel features exposed at a line dose of 0.09 nC·cm−1. The SE contrast measurement reveals continuous lines with 8.5 nm line width and 17 nm pitch. Figure 7b shows that 6 nm lines on 12 nm pitch were resolvable but

• the lines were broken at a line dose of 0.04 nC·cm−1, which is equivalent to 25 ions per nanometre, i.e., a signal-to-noise ratio of 5:1. The line discontinuity is caused by shot noise producing missing pixels. Thus 6 nm represents the current limit of 1:1 dense features using SHIBL to expose HM-01A

Biomimetic surface structures in steel fabricated with femtosecond laser pulses: influence of laser rescanning on morphology and wettability

• Camilo Florian Baron,
• Alexandros Mimidis,
• Daniel Puerto,
• Evangelos Skoulas,
• Emmanuel Stratakis,
• Javier Solis and
• Jan Siegel

Beilstein J. Nanotechnol. 2018, 9, 2802–2812, doi:10.3762/bjnano.9.262

• , Neff_2D = 407), which are self-organized cone structures distributed over the irradiated surface. A higher fluence with a higher number of pulses evolves into nonuniform structures without any visible order, indicating an excessive energy dose and resulting in severe damage of the material ( = 2.3 J/cm2

Disorder in H⁺-irradiated HOPG: effect of impinging energy and dose on Raman D-band splitting and surface topography

• Lisandro Venosta,
• Noelia Bajales,
• Sergio Suárez and
• Paula G. Bercoff

Beilstein J. Nanotechnol. 2018, 9, 2708–2717, doi:10.3762/bjnano.9.253

• technique to characterize different samples and gain new insights on the splitting of the D band into two components (D1 and D2), trying to correlate this feature of the vibrational spectrum with the impinging energy and dose. An increased ID2/IG ratio in comparison with ID1/IG was observed in the

• irradiated samples. This behavior indicates that the impinging energy mainly affects the D1 component, while the D2 component is strongly dominated by the dose. We expect a larger contribution of defects (originating from the rupture of C–C sp2 symmetry through the formation of C–H sp3 bonds) to the D2

• density of HOPG. Now, we intend to contribute to the understanding of structural changes in graphitic materials generated by intentional ion irradiation of HOPG surfaces. In this work we analyze the effect of dose and impinging energy of H+ ions on the D band of irradiated HOPG, which exhibits a double

Pattern generation for direct-write three-dimensional nanoscale structures via focused electron beam induced deposition

• Lukas Keller and
• Michael Huth

Beilstein J. Nanotechnol. 2018, 9, 2581–2598, doi:10.3762/bjnano.9.240