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

• multifaceted instrument enabling a broad range of applications beyond imaging in which the finely focused helium ion beam is used for a variety of defect engineering, ion implantation, and nanofabrication tasks. Operation of the ion source with neon has extended the reach of this technology even further. This

• electrons also permits high-quality imaging of electrically insulating materials, such as biological samples, thus avoiding the need for conductive coatings that can introduce artifacts and obscure nanoscale surface features [6][7]. Through extension of the technology to enable operation of the ion source

• field. For previous reviews, the reader is referred to [9][10][11][12][13]. Key features of the beam and the beam–sample interaction The enabling foundation of all HIM applications, from imaging to nanofabrication, comes down to the unique characteristics of the beam and its interaction with the sample

High-yield synthesis of silver nanowires for transparent conducting PET films

• Gul Naz,
• Hafsa Asghar,
• Muhammad Ramzan,
• Muhammad Arshad,
• Rashid Ahmed,
• Muhammad Bilal Tahir,
• Bakhtiar Ul Haq,
• Nadeem Baig and
• Junaid Jalil

Beilstein J. Nanotechnol. 2021, 12, 624–632, doi:10.3762/bjnano.12.51

• AgNWs were then used for various characterizations. The prepared solution was further diluted and used for UV–vis spectroscopy and PL spectroscopy. Another batch of the same reaction solution was dried and crushed into fine powder used for SEM imaging. This modified synthesis method is shown

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• , which agrees well with the previous experimental and theoretical studies [27][45]. 3D force maps, obtained via constant-height Δf imaging, allow us to test the mechanical stability of the monolayer substrate in the short-range force regime. Using the AFM tip as a nanoindenter we probe its effect on the

Influence of electrospray deposition on C₆₀ molecular assemblies

• Antoine Hinaut,
• Sebastian Scherb,
• Sara Freund,
• Zhao Liu,
• Thilo Glatzel and
• Ernst Meyer

Beilstein J. Nanotechnol. 2021, 12, 552–558, doi:10.3762/bjnano.12.45

• nanometers in size are observed, suggesting a limited influence of the HV-ESD method. The C60 molecules cover step edges and form monolayer islands, similar to TE. High-resolution imaging of the islands, shown in Figure 2c, confirms the hexagonal lattice arrangement of C60 with a lattice parameter close to 1

• substrate can lead to a charging of the surface induced by the deposition of charged species. This can have a strong influence on the surface local charge and, eventually, on island formation [15] during HV-ESD. To improve scan conditions, imaging was performed a few hours after HV-ESD to reduce the

• be a good alternative to TE when working with non-volatile molecules and has proven to be compatible with sensitive techniques, such as low-temperature AFM with CO tip imaging [10][12]. Nevertheless, we have shown some influence on the surfaces and the formation of molecular assemblies that should

On the stability of microwave-fabricated SERS substrates – chemical and morphological considerations

• Limin Wang,
• Aisha Adebola Womiloju,
• Christiane Höppener,
• Ulrich S. Schubert and
• Stephanie Hoeppener

Beilstein J. Nanotechnol. 2021, 12, 541–551, doi:10.3762/bjnano.12.44

• carbon tape. To improve the contrast and to reduce the potential charging effect, the samples were sputter-coated with platinum (Pt) with a coating thickness of 4 nm. The SEM imaging was performed with a field-emission scanning electron microscope (Sigma VP, Carl Zeiss AG, Jena, Germany) at an

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

• blood tests, urinalysis, sputum induction, and magnetic resonance imaging of the chest and abdomen. After oral exposure, the silver content in the serum and urine was analyzed and no clinically abnormal changes were noted in the lungs, heart, or abdominal organs. Also, no morphological changes were

The impact of molecular tumor profiling on the design strategies for targeting myeloid leukemia and EGFR/CD44-positive solid tumors

• Nikola Geskovski,
• Nadica Matevska-Geshkovska,
• Simona Dimchevska Sazdovska,
• Marija Glavas Dodov,
• Kristina Mladenovska and
• Katerina Goracinova

Beilstein J. Nanotechnol. 2021, 12, 375–401, doi:10.3762/bjnano.12.31

• , acquiring this targeted approach could enable the employment of higher doses that will result in a more effective therapy with fewer side effects. In vivo imaging of the epithelium of BM blood vessels revealed that the vasculature expresses the adhesion molecule E-selectin and the chemoattractant stromal

Structural and optical characteristics determined by the sputtering deposition conditions of oxide thin films

• Petronela Prepelita,
• Florin Garoi and
• Valentin Craciun

Beilstein J. Nanotechnol. 2021, 12, 354–365, doi:10.3762/bjnano.12.29

• ). The system is equipped with an X-ray source and an EDX unit with elementary energy dispersion spectroscopy (EDS). These analyses employ different magnifications depending on the quality of the thin films and the structure of their surface. Using cross-section imaging and a magnification of 20000×, it

• properties. Transparent oxides are an attractive class of plasmonic materials which are under intense study for their integration into low-loss metamaterial structures and a series of applications in transformation optics, sensors, and imaging. Here we used oxide thin films and studied their optical

Intracranial recording in patients with aphasia using nanomaterial-based flexible electronics: promises and challenges

• Qingchun Wang and
• Wai Ting Siok

Beilstein J. Nanotechnol. 2021, 12, 330–342, doi:10.3762/bjnano.12.27

• processing. This review presents findings on aphasia, an impairment in language and communication, and discusses how different brain imaging techniques, including positron emission tomography, magnetic resonance imaging, and iEEG, have advanced our understanding of the neural networks underlying language and

• neuroimaging methods such as positron emission tomography (PET), magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), electroencephalography (EEG), magnetoencephalography (MEG), and intracranial electroencephalography (iEEG). Each of these methods has

• determine water diffusion in different dimensions in terms of magnitude and direction. DTI offers an opportunity to measure the microstructural characteristics of white matter and allows for the examination of how distinct brain regions are correlated. fMRI and PET extend traditional structural imaging to

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

• ranging from several days to one or two months. For imaging and nanofabrication, only one of the three atoms is selected. This nearly ideal point source allows not only for high-resolution imaging but also for the milling of smallest geometric features [5][6][7]. Furthermore, large-area machining is

• reduce patterning quality. Hence, interim imaging and, thus, unintended ion beam modification can be avoided. The FIB patterning process relies on the beam control that is well advanced and readily available in commercial ion microscopes. Ion microscopes of all manufacturers are equipped with patterning

• times, and their pitches. The beam profile depends on the beam settings, given by acceleration voltage, extractor voltage (named ‘best imaging voltage’ (BIV) in the case of He ion microscopy), and the beam current, as well as on the quality of the focus. The beam profile is unknown a priori but can be

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

• -AgNPs). UV–vis spectra exhibited a characteristic absorption peak at 390 nm for Ag (Supporting Information File 1, Figure S1b). TEM imaging of the AgNP stock indicated a mean core size of 16.9 ± 0.3 nm and confirmed a spherical shape of NPs (Supporting Information File 1, Figure S1c and Figure S1d

• tables. Acknowledgements We would like to thank the Clemson University Electron Microscopy Facility for STEM imaging. We are also grateful to Kandy Velázquez for helpful discussions throughout this project. Funding We thank the Smartstate Center for Environmental Nanoscience and Risk (CENR), the NSF

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

• imaging techniques. The results revealed that the route of MNP entry into cells strongly depends on the surface chemistry of the MNPs. While serum bovine albumin-coated MNPs entered the cells via clathrin-mediated endocytosis (CME), caveolin-mediated endocytosis (CavME) or lipid rafts were preferentially

• ; Introduction Magnetic iron oxide nanoparticles (MNPs) as chemically inert material have been increasingly employed as contrast agents in magnetic resonance imaging (MRI), positron emission tomography (PET), and near-infrared fluorescence (NIRF) imaging [1]. The superparamagnetic properties of MNPs make them

• software provided by the manufacturer. As the color of MNPs is dark brown and may interfere with the spectrophotometry readings, the net readings were corrected according to Häfeli and co-workers [71]. Time-lapse imaging of cells Exponentially growing A549 cells were seeded on a 24-well tissue plate, at a

Gold(I) N-heterocyclic carbene precursors for focused electron beam-induced deposition

• Cristiano Glessi,
• Aya Mahgoub,
• Cornelis W. Hagen and
• Mats Tilset

Beilstein J. Nanotechnol. 2021, 12, 257–269, doi:10.3762/bjnano.12.21

• Sciences, Dept. Imaging Physics, Lorentzweg 1, 2628CJ Delft, Netherlands 10.3762/bjnano.12.21 Abstract Seven gold(I) N-heterocyclic carbene (NHC) complexes were synthesized, characterized, and identified as suitable precursors for focused electron beam-induced deposition (FEBID). Several variations on the

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

• been determined [15]. In the course of adhesion-related cell processes considerable nanoscale rearrangements take place inside and on the surface of the cells. Some of them are difficult to address by optical imaging methods due to limited resolution or unduly high light exposure. Scanning probe

• the only method capable of nanoscopic three-dimensional imaging of living cells without the application of dye labels or other modifications. Though SICM was developed already in 1989 [19], it was not much exploited until the method was used to image a number of murine and human cell lines [23

• ruffles moving beneath the pipette opening. Slightly higher rms amplitudes may also be due to different temperature because fixed cells are measured at room temperature, while live-cell imaging is carried out at 37 °C. Frequency response behavior Owing to the fact that morphological changes at the cell

Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

• Rafal Zuzak,
• Marek Szymonski and
• Szymon Godlewski

Beilstein J. Nanotechnol. 2021, 12, 232–241, doi:10.3762/bjnano.12.19

• consider now high-resolution imaging analysis. Already within the STM image in Figure 3a, we can notice lobes that differ in their apparent height. The separation between differently bright nearest neighboring lobes, which reaches approximately 0.7 nm, suggests that they originate from the same molecule

• . We can introduce a tentative model of the imaging, which assumes that the two unevenly bright lobes correspond to the two outer benzene rings of the same molecule. This is shown schematically in Figure 3c, where the upper panels show schematically the STM top view. The two lobes originating from the

• therefore we can conclude that the island extension is always associated with the appearance of two rows of lobes. Thus, it seems reasonable to assume that the two lobes originate from a single molecule, in accordance with the tentative model of imaging shown in Figure 3c. For clarity, the anticipated

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

• can be optimized either for most efficient signal collection or for maximum image contrast. The designed setup allows for the imaging of thin low-density materials that otherwise provide little signal or contrast and for a clear end-point detection in the fabrication of nanopores. In addition, the

• instrument that is used to drive research across multiple disciplines. While it can be operated like a scanning electron microscope (SEM) for imaging applications, it offers a higher resolution at a larger depth of field than SEMs [1]. A major advantage of the technology besides its surface-sensitive imaging

• five times more secondary electrons (SE) than an SEM [5]) is advantageous when working with beam-sensitive samples. An overview of the imaging as well as recently added analytical capabilities using secondary ion mass spectroscopy can be found in a recent review [6]. Beyond imaging, the HIM has been

Determination of elastic moduli of elastic–plastic microspherical materials using nanoindentation simulation without mechanical polishing

• Hongzhou Li and
• Jialian Chen

Beilstein J. Nanotechnol. 2021, 12, 213–221, doi:10.3762/bjnano.12.17

• –displacement data alone. This avoids the need to measure the area of indentation by imaging and facilitates the measurement of properties at the sub-micrometer scale. During nanoindentation, a diamond indenter with a geometry known to high precision is pressed into the surface of the specimen with increasing

TiO_x/Pt₃Ti(111) surface-directed formation of electronically responsive supramolecular assemblies of tungsten oxide clusters

• Marco Moors,
• Yun An,
• Agnieszka Kuc and
• Kirill Yu. Monakhov

Beilstein J. Nanotechnol. 2021, 12, 203–212, doi:10.3762/bjnano.12.16

• , theory-supported STM measurements at liquid nitrogen temperatures have been selected as an ideal characterization technique. This is due to the fact that it not only allows high-resolution imaging on the nanoscale, but the STM tip may also act as a charge-injecting or depleting electrode for the

A review on the biological effects of nanomaterials on silkworm (Bombyx mori)

• Sandra Senyo Fometu,
• Guohua Wu,
• Lin Ma and
• Joan Shine Davids

Beilstein J. Nanotechnol. 2021, 12, 190–202, doi:10.3762/bjnano.12.15

• in order to deal with foreign cells. Quantum dots have unique optical properties that are used in biological imaging [147][148][149][150]. They are also known for their size-dependent cytotoxicity [151][152]. Silkworms were subjected to doses of 32 mM of CdTe QDs, 1 µg/µL of citric acid–nitrogen

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

• Helium ion microscopy (HIM) offers the opportunity to obtain direct views of biological samples such as cellular structures, virus particles, and microbial interactions. Imaging with the HIM combines sub-nanometer resolution, large depth of field, and high surface sensitivity. Due to its charge

• virus particles lying on top of the membrane. After prolonged imaging, it was found that ion-induced deposition of hydrocarbons from the vacuum renders the sample sufficiently conductive to allow for imaging even without charge compensation. The presented images demonstrate the potential of the HIM in

• bioimaging, especially for the imaging of interactions between viruses and their host organisms. Keywords: bioimaging; cell membrane; charge compensation; helium ion microscopy; SARS-CoV-2; Vero E6 cells; Introduction The last decade of helium ion microscopy (HIM) was characterized by a rapid exploration

Mapping the local dielectric constant of a biological nanostructured system

• Wescley Walison Valeriano,
• Rodrigo Ribeiro Andrade,
• Juan Pablo Vasco,
• Angelo Malachias,
• Bernardo Ruegger Almeida Neves,
• Paulo Sergio Soares Guimarães and
• Wagner Nunes Rodrigues

Beilstein J. Nanotechnol. 2021, 12, 139–150, doi:10.3762/bjnano.12.11

• h is directly determined via AFM imaging. The microscope control software also determines the resonance frequency f0 and the elastic constant K of the cantilever using the thermal tune method [30][31]. A critical parameter is the tip–sample distance z, that consists of the height Hlift plus the

A review on the green and sustainable synthesis of silver nanoparticles and one-dimensional silver nanostructures

• Sina Kaabipour and
• Shohreh Hemmati

Beilstein J. Nanotechnol. 2021, 12, 102–136, doi:10.3762/bjnano.12.9

• delivery [1][2][3][4][5][6], nanomedicine [7][8][9][10], food packaging [11][12][13], aseptic procedures [14][15][16], correlative microscopy [17], imaging [18][19][20][21][22], optics [23][24], microelectronics [25][26][27], three dimensional (3D) printing [27][28][29][30][31], renewable energy [32][33

• groups [263]. Although viral templates have not been investigated as much as other approaches, viral template-mediated Ag nanostructures have been demonstrating promising potential in targeted imaging and therapeutic delivery systems [272]. In addition, they can be used to synthesize 1D Ag nanostructures

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

• distributed patch islands at low OD, or large patch clusters at high OD. The drop has been preserved in a small container along with a small vessel filled with water to prevent drying. A coverage rate of more than 90% could be achieved, but AFM imaging has shown that a higher coverage rate is associated with

• the final linker is shown in Figure 2a. The functionalization was tested with the His-tagged fluorescent protein mTurqoise. Confirmation of successful functionalization was provided by fluorescence imaging as seen in Figure 2b. The images show that the complex bonds formed with His-labeled proteins

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

• : cytotoxicity; ion release; RAW 264.7 macrophage cell line; silica coating; upconversion nanoparticles; Introduction Upconversion nanoparticles (UCNPs) convert excitation radiation with long wavelengths to a short-wavelength emission. Since biological molecules do not have an upconversion mechanism, imaging

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

• of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland 10.3762/bjnano.12.1 Abstract Scanning helium-ion microscopy (HIM) is an imaging technique with sub-nanometre resolution and is a powerful tool to resolve some of the tiniest structures in biology. In many aspects, the HIM

• resembles a field-emission scanning electron microscope (FE-SEM), but the use of helium ions rather than electrons provides several advantages, including higher surface sensitivity, larger depth of field, and a straightforward charge-compensating electron flood gun, which enables imaging of non-conductive

• samples, rendering HIM a promising high-resolution imaging technique for biological samples. Starting with studies focused on medical research, the last decade has seen some particularly spectacular high-resolution images in studies focused on plants, microbiology, virology, and geomicrobiology. However