Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• analyte. The magnetic bead (MaB) architecture is composed of a 15 nm iron oxide (Fe3O4) superparamagnetic core encased in a silica shell. The DNA strands are conjugated to the polymeric brush using a flexible linker. The brush permits passage of the nanoparticles through cell membranes, and prevents

Physical constraints lead to parallel evolution of micro- and nanostructures of animal adhesive pads: a review

• Thies H. Büscher and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2021, 12, 725–743, doi:10.3762/bjnano.12.57

• recruited in this case. Such a mechanism may secure a stable position of an animal on a ceiling. As the shear forces are applied proximally towards the body in this situation, and because of a stronger friction in this direction due to an intimate contact between the membranes/spatulae, the pad sliding can

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• selective helium ion irradiation has since been used to manipulate heat flow in suspended crystalline silicon membranes, patterning concentric circles at variable dose to demonstrate a microscale thermal cloak [35] (Figure 2h). In a subsequent study by Jin et al., dose-controlled localized helium ion

• the layers was undesired. Membrane folding Recently, several papers on FIB-enabled nanoscale kirigami have been published using the gallium FIB to mill line patterns in free-standing membranes (equivalent to traditional macroscale paper cuts) followed by localized gallium ion implantation to induce

• ] (Figure 4d). In this work by Arora et al., free-standing cantilevers in silicon nitride membranes that had been prepared by photolithography were irradiated near the base with helium ions at different energies. Upwards versus downwards bending was observed, depending on the implantation depth profiles. It

The preparation temperature influences the physicochemical nature and activity of nanoceria

• Robert A. Yokel,
• Wendel Wohlleben,
• Johannes Georg Keller,
• Matthew L. Hancock,
• Jason M. Unrine,
• D. Allan Butterfield and
• Eric A. Grulke

Beilstein J. Nanotechnol. 2021, 12, 525–540, doi:10.3762/bjnano.12.43

• section “Cerium quantification”. The dialysis system has been described [39][40]. Nanoceria (500 μg cerium as nanoceria in 1 mL) was loaded into Slide-A-LyzerTM dialysis cassettes with 2 kD MWCO regenerated cellulose membranes (66203) immersed in a 200 mL bath at pH 4.5 made iso-osmotic with sodium

A review on nanostructured silver as a basic ingredient in medicine: physicochemical parameters and characterization

• Gabriel M. Misirli,
• Kishore Sridharan and
• Shirley M. P. Abrantes

Beilstein J. Nanotechnol. 2021, 12, 440–461, doi:10.3762/bjnano.12.36

• antimicrobial activities: smaller particles are more efficient to kill bacteria than larger ones. This could be attributed to the higher surface areas that facilitate the attachment to cell membranes [8]. In addition to the different sizes and shapes that AgNPs can have, other metallic layers can be added to

• condition characterized by pigmentary changes secondary to exposure to silver salts which accumulate in the skin and mucous membranes. The toxicity of AgNPs is closely related to the release of Ag+ [57]. Studies with human mesenchymal stem cells (hMSCs) treated, under cell culture conditions, with different

Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing

• Christian Preischl,
• Linh Hoang Le,
• Elif Bilgilisoy,
• Armin Gölzhäuser and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26

• arbitrary substrates or grids to obtain free-standing 2D membranes [25]. The specific choice of the self-assembling molecules determines the thickness, porosity, stiffness, and the mechanical/electrical properties of the resulting CNM [26][27]. The SAMs that are used for the fabrication of CNMs consist of

The patterning toolbox FIB-o-mat: Exploiting the full potential of focused helium ions for nanofabrication

• Victor Deinhart,
• Lisa-Marie Kern,
• Jan N. Kirchhof,
• Sabrina Juergensen,
• Joris Sturm,
• Enno Krauss,
• Thorsten Feichtner,
• Sviatoslav Kovalchuk,
• Michael Schneider,
• Dieter Engel,
• Bastian Pfau,
• Bert Hecht,
• Kirill I. Bolotin,
• Stephanie Reich and
• Katja Höflich

Beilstein J. Nanotechnol. 2021, 12, 304–318, doi:10.3762/bjnano.12.25

• ]. The fabrication of the samples starts by depositing the magnetic multilayer onto 150 nm thick silicon nitride membranes via magnetron sputtering. The membranes are almost transparent for soft X-rays, which are later employed for imaging of the samples. Subsequently, the multilayer film is locally

Characterization, bio-uptake and toxicity of polymer-coated silver nanoparticles and their interaction with human peripheral blood mononuclear cells

• Sahar Pourhoseini,
• Reilly T. Enos,
• Angela E. Murphy,
• Bo Cai and
• Jamie R. Lead

Beilstein J. Nanotechnol. 2021, 12, 282–294, doi:10.3762/bjnano.12.23

• concentration of 1000 µg·L−1, with the remainder lost to surfaces such as containers or filter membranes. To confirm the results in the medium, and to compare the dissolution in RPMI and UHPW, the dissolution test was repeated using AgNO3 in UHPW and RPMI medium at two concentrations (500 and 1000 µg·L−1

Differences in surface chemistry of iron oxide nanoparticles result in different routes of internalization

• Barbora Svitkova,
• Vlasta Zavisova,
• Veronika Nemethova,
• Martina Koneracka,
• Miroslava Kretova,
• Filip Razga,
• Monika Ursinyova and
• Alena Gabelova

Beilstein J. Nanotechnol. 2021, 12, 270–281, doi:10.3762/bjnano.12.22

• ) without affecting CME and micropinocytosis [50], MBCD is not so specific. It can affect components of the transport machinery involved in multiple endocytic pathways including CME, depending on the concentration used [51]. F binds cholesterol within membranes while N perturbs cholesterol levels by

• proteins were boiled in Laemmli buffer and separated on a 10% polyacrylamide SDS-PAGE gel. After transfer of proteins onto nitrocellulose membranes the following primary antibodies were used: anti-Clathrin Heavy Chain (P1663) (#2410), anti-Caveolin-1 (#3238), anti-Phospho-Caveolin-1 (Tyr14) (#3251), anti

The nanomorphology of cell surfaces of adhered osteoblasts

• Christian Voelkner,
• Mirco Wendt,
• Regina Lange,
• Max Ulbrich,
• Martina Gruening,
• Susanne Staehlke,
• Barbara Nebe,
• Ingo Barke and
• Sylvia Speller

Beilstein J. Nanotechnol. 2021, 12, 242–256, doi:10.3762/bjnano.12.20

• may correspond to ca. 10 MPa, assuming 1 nN loading force and 5 nm tip radius. Though the resulting artificial depression depths on the cellular membranes are about half a micrometer already at 1 nN, AFM is useful to measure the cortical actin network underneath the membrane [18]. Regarding the

• ). Such a SICM signature is compatible with that of a primary cilium [28]. Dorsal ruffles The morphologies of osteoblast membranes reveal sheet-like protrusions, so-called ruffles. In general, they cover the whole cell surface. They are quite thin (similar to the thickness of filopodia of ca. 100 nm) and

• membranes in the rim region tend to appear slightly smoother (less ruffled) on cells that have formed large adhesion interface areas. This may indicate that membrane supply is an issue during faster spreading. Rim edge heights In Figure 9a we show a typical example of the rim step edge height of an

Scanning transmission helium ion microscopy on carbon nanomembranes

• Daniel Emmrich,
• Annalena Wolff,
• Nikolaus Meyerbröker,
• Jörg K. N. Lindner,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 222–231, doi:10.3762/bjnano.12.18

• principle is based on a secondary electron conversion holder with an exchangeable aperture strip allowing its acceptance angle to be tuned from 3 to 98 mrad. The contrast mechanism and performance were investigated using freestanding nanometer-thin carbon membranes. The results demonstrate that the detector

• detector is able to determine the thickness of membranes with sub-nanometer precision by quantitatively evaluating the image signal and comparing the results with Monte Carlo simulations. The thickness determined by the dark-field transmission detector is compared to X-ray photoelectron spectroscopy and

• established as a key nanofabrication tool for milling [7][8][9], defect engineering [10][11], and resist-based lithography [12][13], overcoming the resolution limitations of other FIB techniques [14][15]. Both bulk samples as well as thin membranes have been structured using the HIM. On membranes, the sputter

Imaging of SARS-CoV-2 infected Vero E6 cells by helium ion microscopy

• Natalie Frese,
• Patrick Schmerer,
• Martin Wortmann,
• Matthias Schürmann,
• Matthias König,
• Michael Westphal,
• Friedemann Weber,
• Holger Sudhoff and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 172–179, doi:10.3762/bjnano.12.13

• infection of approximately 1 (MOI 1) and an incubation time of 18 h. The surface of the infected cells is covered by a number of micrometer-sized vesicles and segments of cell membranes, which is a first indication that apoptosis occurred during viral replication. Regularly shaped particles below 100 nm

Fusion of purple membranes triggered by immobilization on carbon nanomembranes

• René Riedel,
• Natalie Frese,
• Fang Yang,
• Martin Wortmann,
• Raphael Dalpke,
• Daniel Rhinow,
• Norbert Hampp and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 93–101, doi:10.3762/bjnano.12.8

• protein bacteriorhodopsin (BR) and lipid molecules [3], can be separated from the cytoplasmic membrane of Halobacterium salinarum and have been intensively studied [4][5][6]. Due to its robustness, PM quickly became one of the best-characterized natural membranes [7]. It is a two-dimensional crystal with

Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• short tip that can be considered as a rigid body vertically attached to the tuning fork prong. However, soft biological samples, such as living cells and lipid membranes [13][14][15], must be immersed in a liquid environment to maintain their original properties. In order to avoid immersion of the

Effect of different silica coatings on the toxicity of upconversion nanoparticles on RAW 264.7 macrophage cells

• Cynthia Kembuan,
• Helena Oliveira and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 35–48, doi:10.3762/bjnano.12.3

• or particles adsorbed onto cellular membranes, relying on the fact that when cells internalize nanoparticles they increase their internal complexity [66][67]. Several publications have shown that side-scattering correlates with the concentration of nanoparticles attached to or taken up by cells [67

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

• attachment of bacterial parasites to the outer membranes of bacteria at high resolution in, at least compared to TEM, a relatively natural state makes HIM a very powerful tool for the investigation of living antibiotics. The work on the life cycle of the bacterial predator Bdellovibrio bacteriovorus by Said

• to be directly and clearly visualised.” Using HIM, Schürmann et al. impressively showed how closely ultrastructural details of cell membranes visualised by HIM are linked to sample preparation [16]. In the study, lipid nanodomains in mammalian cells were investigated. HIM was used to image osmium

• tetroxide-fixed, uncoated, and critical-point-dried human neurons and mouse hippocampal neurons. The achieved lateral resolution of 1.5 nm allowed for visualising pits in the ultrastructure of the cell membranes. Based on that finding the authors hypothesised “that the pit-like domains are a direct

Imaging and milling resolution of light ion beams from helium ion microscopy and FIBs driven by liquid metal alloy ion sources

• Nico Klingner,
• Gregor Hlawacek,
• Paul Mazarov,
• Wolfgang Pilz,
• Fabian Meyer and
• Lothar Bischoff

Beilstein J. Nanotechnol. 2020, 11, 1742–1749, doi:10.3762/bjnano.11.156

• helium beam were measured by examining sputtered lines [42] as well as pores [43] in membranes. Gallium is used and optimized for industrial and scientific applications and sputtering beam profiles were measured by TEM [44][45]. The additional influence of the required ExB filter for multi-element or

• spot size is always smaller than the measured trench width could be the different sample types used for the measurements. While ultimate imaging resolutions are typically measured as an edge contrast on thin freestanding membranes, trenches are typically milled in a metal layer of a few nanometers

• thickness. Milling membranes removes their support from one side and dangling bonds can lead to morphological changes making milling tests difficult to interpret. In metal layers of a few nanometers thickness, sputter redeposition can take place, which is not taken into account in our static SRIM simulation

Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

• Serguei Chiriaev,
• Luciana Tavares,
• Vadzim Adashkevich,
• Arkadiusz J. Goszczak and
• Horst-Günter Rubahn

Beilstein J. Nanotechnol. 2020, 11, 1693–1703, doi:10.3762/bjnano.11.151

• ][16]. It has also been demonstrated that it acts as a type of ion-beam resist in the fabrication of micro- and nanopore membranes and templates for nanowires by chemical etching of through-holes along ion tracks produced by high-energy ions [17][18]. In contrast to PMMA and PC polymers, PDMS is a

A self-powered, flexible ultra-thin Si/ZnO nanowire photodetector as full-spectrum optical sensor and pyroelectric nanogenerator

• Liang Chen,
• Jianqi Dong,
• Miao He and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1623–1630, doi:10.3762/bjnano.11.145

• limits their application in the field of flexible electronics. Recently, the design of flexible devices with Si membranes as building blocks has been explored. These devices have become promising candidates for the use as flexible PDs due to many advantages, such as good compatibility, working in a harsh

Cu₂O nanoparticles for the degradation of methyl parathion

• Juan Rizo,
• David Díaz,
• Benito Reyes-Trejo and
• M. Josefina Arellano-Jiménez

Beilstein J. Nanotechnol. 2020, 11, 1546–1555, doi:10.3762/bjnano.11.137

• rising consensus on the damage that these reactive species, formed during the photocatalytic reactions, cause to cell membranes by peroxidation of the polyunsaturated phospholipids [34]. This leads to the subsequent loss of activity that relies on an intact membrane, and ultimately to the death of

Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

• Matías Guerrero Correa,
• Fernanda B. Martínez,
• Cristian Patiño Vidal,
• Camilo Streitt,
• Juan Escrig and
• Carol Lopez de Dicastillo

Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129

• particle sizes, are listed in Table 2. The atomic layer deposition method is employed to grow metal oxide and metallic three-dimensional nanostructures using porous alumina membranes [41], electrostatically spun nanofibers [39][40] or electrosprayed spherical particles [38] as templates. As Figure 1 shows

Transient coating of γ-Fe₂O₃ nanoparticles with glutamate for its delivery to and removal from brain nerve terminals

• Konstantin Paliienko,
• Artem Pastukhov,
• Michal Babič,
• Daniel Horák,
• Olga Vasylchenko and
• Tatiana Borisova

Beilstein J. Nanotechnol. 2020, 11, 1381–1393, doi:10.3762/bjnano.11.122

• measurements were carried out using the potential-sensitive fluorescent dye rhodamine 6G, which binds to negatively charged membranes. The addition of synaptosomes to the dye-containing medium was accompanied by a partial decrease in fluorescence signal due to rhodamine 6G binding to the synaptosomal plasma

Structure and electrochemical performance of electrospun-ordered porous carbon/graphene composite nanofibers

• Yi Wang,
• Yanhua Song,
• Chengwei Ye and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 1280–1290, doi:10.3762/bjnano.11.112

• delivered by the flow pump at a 1 mL·h−1 flow rate. The applied spinning voltage was 18 kV, the spinning distance was kept at 18 cm, the distance between two paralleled electrodes was 5 cm, the diameter of ring was 21 cm, and the voltage applied to the ring was 5 kV. Then the PGCNF membranes were cut into a

• after carbonization and the reaction between the polymer and graphene. Electrochemical evaluation and capacitive deionization experiments The CGCNF membranes were cut into small pieces (1.0 cm × 1.0 cm) and oven- dried (DZF-6050, Shanghai Jinghong Scientific Instrument Co. Ltd., China) for one hour at

• 50 °C. Then the dried CGCNF membranes were weighed to an accuracy of 0.001 g and clamped to a platinum plate electrode holder. After clamping, the CGCNF membranes were directly used as cell electrodes and immersed into an electrolyte solution. The electrochemical measurements were performed in a

Magnetic-field-assisted synthesis of anisotropic iron oxide particles: Effect of pH

• Andrey V. Shibaev,
• Petr V. Shvets,
• Darya E. Kessel,
• Roman A. Kamyshinsky,
• Anton S. Orekhov,
• Sergey S. Abramchuk,
• Alexei R. Khokhlov and
• Olga E. Philippova

Beilstein J. Nanotechnol. 2020, 11, 1230–1241, doi:10.3762/bjnano.11.107

• binding to and an enhanced retention at the target sites [26] due to their larger contact area and multidentate interactions with the cell membranes. Thus, rod-like nanoparticles are preferred in many applications. However, their synthesis is more complicated than the synthesis of nanospheres since the

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• eliminated the pathogenic P. aeruginosa upon NIR irradiation [49]. Gold nanorods were also applied to efficiently ablate (up to 97%) S. aureus upon NIR laser irradiation [50]. In these studies, the results suggested that the thermal damage of the bacterial membranes led to bacterial death. In 2013, the first

• , such as silver or copper sulfide, they acquire a dual effect as shown for the copper sulfide nanoparticle case. Another example is carbon nanotubes which can damage bacterial membranes without the application of NIR light exposure [109]. However, the nanoparticle stability should always be verified