Silver nanoparticles nucleated in NaOH-treated halloysite: a potential antimicrobial material

• Yuri B. Matos,
• Rodrigo S. Romanus,
• Mattheus Torquato,
• Edgar H. de Souza,
• Rodrigo L. Villanova,
• Marlene Soares and
• Emilson R. Viana

Beilstein J. Nanotechnol. 2021, 12, 798–807, doi:10.3762/bjnano.12.63

• , and HNT-8 were recorded with TEM, while sample HNT-8 was also measured with XRD. (XRD was also performed for HNT-0 and HNT-4 but omitted from this report because it did not show any significant difference from HNT-8). Silver nanoparticle synthesis To synthesize silver nanoparticles, 10 g of HNT (from

• and DSC analysis, from room temperature up to 600 °C, at constant heating of 20 °C/min. In order to observe the phases identified in the DSC/TGA measurements, four 10 g samples of HNT-8 were loaded with AgNO3 using the process described in section “Silver nanoparticle synthesis” and heated up to 65

• , to a concentration of 105 CFU/mL. These new 105 CFU/mL suspensions were then divided into ten tubes each, and to each were added the following concentrations of Ag/HNT-0 or Ag/HNT-8: 3, 6, 12, 25, 50, 100, 200, 400, 800, and 1600 ppm. Finally, each nanoparticle + bacteria suspension was incubated

Recent progress in actuation technologies of micro/nanorobots

• Ke Xu and
• Bing Liu

Beilstein J. Nanotechnol. 2021, 12, 756–765, doi:10.3762/bjnano.12.59

• this, the new microrobot is expected to be used in targeted drug delivery and other biomedical fields. Si et al. [27] proposed a theoretical concept of a nanorobot consisting of a nanoparticle and four single-stranded DNAs placed on a quad-nanopore device for motion control. When an electric field is

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

• processes of MNPs are adopted to fabricate MNRs [37]. A rotating magnetic field was often used to break particle chains into shorter fragments. As the magnetic field changes, the particle chain will be broken and re-formed. While disassembling the paramagnetic nanoparticle chains of MNRs, it is necessary to

• paramagnetic nanoparticle chains. They used a predefined dynamic magnetic field that could controllably spread and fragment the particle chains. This is an effective strategy that shows that the assembly and disassembly process is reversible. Swarms of MNR paramagnetic nanoparticles moved together in the form

• the same time, in order to reduce the chance of reorganization of the fragments a distance between disassembled parts could be established. Through magnetically induced repulsive forces the nanoparticle chains were forced to diffuse in different directions. This new method is of great significance for

Prediction of Co and Ru nanocluster morphology on 2D MoS₂ from interaction energies

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2021, 12, 704–724, doi:10.3762/bjnano.12.56

• interaction between metals and the MoS2 monolayer is of great importance when selecting systems for specific applications. In previous studies the focus has been largely on the strength of the interaction between a single atom or a nanoparticle of a range of metals, which has created a significant knowledge

• catalysts or for preventing islanding of conductive metals. Typically, theoretical studies focus on the adsorption of either single atoms of a series of metals [21][23][24][25][27] or large nanoparticle-like structures [19][20]. In our previous study we identified that while these studies do deliver useful

Fate and transformation of silver nanoparticles in different biological conditions

• Barbara Pem,
• Marija Ćurlin,
• Darija Domazet Jurašin,
• Valerije Vrček,
• Rinea Barbir,
• Vedran Micek,
• Raluca M. Fratila,
• Jesus M. de la Fuente and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2021, 12, 665–679, doi:10.3762/bjnano.12.53

• vivo settings. Keywords: animal tissue; biological media; nanoparticle aggregation; nanoparticle dissolution; nanoparticle reformation; silver nanoparticles; Introduction The global consumption of silver nanoparticles (AgNPs) has been steadily increasing in the last decade and estimated to reach over

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

Stability and activity of platinum nanoparticles in the oxygen electroreduction reaction: is size or uniformity of primary importance?

• Kirill O. Paperzh,
• Anastasia A. Alekseenko,
• Vadim A. Volochaev,
• Ilya V. Pankov,
• Olga A. Safronenko and
• Vladimir E. Guterman

Beilstein J. Nanotechnol. 2021, 12, 593–606, doi:10.3762/bjnano.12.49

• min. A drop of the resulting suspension was applied to a standard copper mesh with a diameter of 3.05 mm, covered with a 5–6 nm thick layer of amorphous carbon. Next, the sample was dried in air at room temperature for 60 min. The histograms of platinum nanoparticle size distribution in the catalysts

• in the catalysts ranged from 1.2 (samples G20 and G25) to 1.3 nm (G30, G35, and G40) (Table 2). A selective electron microscopy study of the synthesized materials (Figure 2) showed that with an increase in the Pt loading in the catalysts, the average nanoparticle size also increased from 2 (G20) to

• the k-type, Θk is the fraction of the nanoparticle surface belonging to the k-type areas. Taking into account platinum nanoparticles with different numbers of catalytically active sites on their surface (different types of faces, edges, vertices, steps) it can be assumed that the smaller the amount of

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

• on the substrates [8], the synthesis of complex nanoparticle structures with tunable interparticle gap sizes [9], the utilization of micro- and nanofabricated structures obtained by lithography techniques [10][11][12] comprising nanodisk arrays [13], nanoholes [14][15], nanocups [16][17

• ], nanogratings [18], or the customization of readily available structures (i.e., HR-DVD templates) [19]. The aim of these developments is not only the optimization of the nanoparticle arrangement to obtain high enhancement factors, but also to guarantee uniformity, homogeneity, the ease of fabrication, low

• typical heating process) which initiates the reduction of the silver salt by ethanol. This triggers a short burst of silver nanoparticle nucleation, which forms reaction seeds on the glass substrate. The strong affinity of the silver ions for the free hydroxyl groups of glass surfaces allows for the

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• near gold nanoparticles protected by various ligands [38][39]. The results of hydrogen bond dynamics and calculated far-IR spectra showed that a well-defined multilayered structure of water is formed close to the surface of the metal nanoparticle. The stabilization of this structure may be additionally

• enhanced by the mobility decrease in the nearest vicinity of the metal nanoparticle and by the increase of the rotational relaxation time and residence time of water molecules surrounding the ion wall in a charged monolayer-protected Au nanoparticle [39]. Assuming that the observed Raman enhancement is

• the water molecules could not be specifically organised onto the metal surface. Therefore, the shape and size of AgNPs may be the crucial point – more precisely, the optical plasmons responsible for the colour of the AgNPs. The location of the enhancement of the electric field around the nanoparticle

Rapid controlled synthesis of gold–platinum nanorods with excellent photothermal properties under 808 nm excitation

• Jialin Wang,
• Qianqian Duan,
• Min Yang,
• Boye Zhang,
• Li Guo,
• Pengcui Li,
• Wendong Zhang and
• Shengbo Sang

Beilstein J. Nanotechnol. 2021, 12, 462–472, doi:10.3762/bjnano.12.37

• , Hitachi, Japan). In the photothermal experiment, an 808 nm CW laser (MDL-III-808 nm, CNI, China) was used to irradiate the nanoparticle solutions, and temperature changes of all samples were recorded with an infrared thermal camera (225s, Fotric, China). Preparation of AuNRs AuNRs were synthesized

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

• determined not only by the large part of the surface atoms, but also by the crystallographic orientation on their surface. The number of atoms on the surface is influenced by the size of the nanoparticle, while the crystallographic orientation depends on the shape of the particles. The surfaces with {111

• –NIR absorption spectroscopy: Metallic nanoparticles are known to emit characteristic colors in the visible region of the electromagnetic spectrum due to a phenomenon known as surface plasmon resonance. The color of a colloidal nanoparticle solution is mainly dependent on the size and shape of the

• equations. Following the discrete dipole approximation (DDA), it is possible to calculate the dipole polarized by the incident light and all the other dipoles in the nanoparticle matrix, in addition to predicting the behavior of their respective spectra. Figure 11 shows the extinction, absorption, and

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

• development and survival have fostered the parallel development of multifunctional bioactive nanomedicines capable of attacking multiple targets, which hold potential to overcome current deficiencies of targeted therapy. Targeting strategies with innovative ligands for nanoparticle surface engineering

Nickel nanoparticle-decorated reduced graphene oxide/WO₃ nanocomposite – a promising candidate for gas sensing

• Ilka Simon,
• Alexandr Savitsky,
• Rolf Mülhaupt,
• Vladimir Pankov and
• Christoph Janiak

Beilstein J. Nanotechnol. 2021, 12, 343–353, doi:10.3762/bjnano.12.28

• Materials Research Center and Institute for Macromolecular Chemistry, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany 10.3762/bjnano.12.28 Abstract We report for the first time the combination of WO3 sensing elements with a non-noble metal–carbon composite, namely a nickel metal nanoparticle

• decomposition approach with rGO synthesized from reduced graphite oxide at 400 °C. It is extremely important that the used rGO is thoroughly dried because of the oxyphilic nature of nickel nanoparticles. Therefore, before the nanoparticle synthesis, the rGO was dried using a turbo molecular pump at 5 × 10−7

• (Figure 3). Therefore, the thermal decomposition of the WO3 xerogel leads to the formation of only one crystalline WO3 phase without crystalline by-products. The average size of WO3 nanoparticle crystallites, calculated from the powder pattern using the Scherrer equation, is 40 nm. The SEM images show

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

• .12.22 Abstract The efficient entry of nanotechnology-based pharmaceuticals into target cells is highly desired to reach high therapeutic efficiency while minimizing the side effects. Despite intensive research, the impact of the surface coating on the mechanism of nanoparticle uptake is not sufficiently

• carrier, are the most frequently used materials for biomedical applications [17][18][19][20]. The impact of the surface chemistry on the mechanism of nanoparticle uptake has not been sufficiently clarified yet. MNPs with comparable basic physicochemical characteristics (e.g., particle size, surface charge

• endocytosis. BSA-SO-MNPs were internalized via CME while PEG-SO-MNPs were taken up via CavME or lipid rafts. These findings confirm the major role of nanoparticle coatings on cellular entry mechanisms. Our data suggest that the effects of endocytic inhibitors on the internalization pathways are rather complex

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

• been reported to improve the weight and the height of tobacco plants and it was also successful in reducing the severity of bacterial wilt caused by Ralstonia solanacearum when compared to control or to other magnesium dioxide nanoparticle concentrations (50 and 150 µg/mL) [23]. The ability of MgO NPs

• µg) did not increase the production of ROS and it was suggested that the its effect on hematopoiesis was self-repaired and the damage to the hematopoietic tissues was limited. Zou et al. [155] studied the efficacy in using silver nanoparticle colloids (AgNPC) to reduce the infection caused by BmNPV

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

• pressure), it can synthesize AgNPs at a lower temperature compared to the sol–gel process alone [144]. Nevertheless, there are some disadvantages regarding the application and feasibility of sol–gel-produced nanoparticles and nanocomposites. For instance, in industrial applications of nanoparticle-doped

• deposition process. Chemical vapor deposition (CVD) and atomic layer deposition (ALD) are among other chemical methods for nanoparticle synthesis. CVD is a method that allows production of nanoparticles on a substrate [241]. The process consists of three steps. First, the addition of a volatile precursor in

• surface. We have recently reviewed engineered TMV and its virus‐like‐particles (VLPs) for synthesis of biotemplated nanomaterials. We also discussed the recent advances on novel barely stripe mosaic virus (BSMV) and its VLP as a novel template for metal nanoparticle synthesis [273][274]. 3.4 Algae

The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• formed under clear nonequilibrium conditions with a dependence on the physicochemical properties of the nanoparticle determined by its size. In this paper, we present the results of a computer simulation study of the condensation process of gold and copper atoms. For the modeling, we used the molecular

• shape corresponding to a minimum of surface energy. Therefore, we can conclude that the Cu3Au clusters precisely hit the substrate in the liquid state through collision, which corroborates the HRTEM image of a flat 2D nanoparticle [3]. Since particles with a maximum size of 5.5 nm (approx. 7000 atoms

•  1. The value of the maximum cluster recorded during the MD modeling was slightly lower (4370 atoms) than that of [3]. This cluster size corresponds to the diameter of approx. 4.76 nm in the case of a spherical cluster. In fact, the nanoparticle with the largest number of atoms (Figure 1) had a

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

• ± 3 nm. Subsequently, the negatively charged particles were functionalized with N-(6-aminohexyl)-3-aminopropyltrimethoxysilane (AHAPS), which provide a positive charge to the nanoparticle surface. Inductively coupled plasma optical emission spectrometry (ICP-OES) measurements revealed that, over the

• -aminopropyltrimethoxysilane (AHAPS), which provides the nanoparticle surface with a positive charge, increasing their interaction with the cell membrane. The particles were characterized by scanning transmission electron microscopy (STEM), dynamic light scattering (DLS), electrophoretic light scattering (ELS), and

• + is released from NaYF4:Yb,Er nanocrystals [19]. Dong et al. reported an analogous observation for the ratio of Y3+ and Gd3+ during a partial disintegration of NaGdF4:Y3+,Tb3+ [61]. This finding can be explained assuming that Y3+ ions are concentrated at the nanoparticle surface and, consequently, are

Free and partially encapsulated manganese ferrite nanoparticles in multiwall carbon nanotubes

• Saja Al-Khabouri,
• Salim Al-Harthi,
• Toru Maekawa,
• Mohamed E. Elzain,
• Ashraf Al-Hinai,
• Ahmed D. Al-Rawas,
• Abbsher M. Gismelseed,
• Ali A. Yousif and
• Myo Tay Zar Myint

Beilstein J. Nanotechnol. 2020, 11, 1891–1904, doi:10.3762/bjnano.11.170

• electronic and magnetic properties. The preparation method of partially encapsulated manganese ferrite enables the formation of a hybrid nanoparticle/tube system, which exhibits properties of manganese ferrite nanoparticles inside and attached to the external surface of the tubes. The effect of having

Towards 3D self-assembled rolled multiwall carbon nanotube structures by spontaneous peel off

• Jonathan Quinson

Beilstein J. Nanotechnol. 2020, 11, 1865–1872, doi:10.3762/bjnano.11.168

• the diameter of the nanoparticle from which they grow [26]. It is established that N-MWCNTs have a larger inner diameter than MWCNTs without an intended doping [6][12][21]. This is also observed in N1/C2 structures (Figure 4) in which the N section has a larger inner diameter and the C section has a

• . For the synthesis performed, a size increase is relatively easy to be achieved since ferrocene, source of the iron atoms, is constantly provided (see Experimental section). However, a size decrease is possible mainly by a size change of the catalyst nanoparticle and by some “loss” of the catalyst (e.g

• reported in our previous work [16]. On each side of the nanoparticle marking the N1/C2 interface, the inner diameter of the tube is drastically changed. One side shows a relatively large inner diameter (in agreement with the N-MWCNT structure) whereas the other side shows a relatively small inner diameter

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

• with prefabricated nanostructures can be implemented in different schemes for nanoparticle control and separation in microfluidic systems [34], and as components of actuators or switches in MEMS [35][36]. Considering the future technological potential of the suggested method it is important to

Cardiomyocyte uptake mechanism of a hydroxyapatite nanoparticle mediated gene delivery system

• Hiroaki Komuro,
• Masahiro Yamazoe,
• Kosuke Nozaki,
• Akiko Nagai and
• Tetsuo Sasano

Beilstein J. Nanotechnol. 2020, 11, 1685–1692, doi:10.3762/bjnano.11.150

• viability were observed among the three concentrations of HAp/pDNA complexes used at 24 and 72 h (Figure 2). The results suggested that HAp exhibits little cytotoxicity within the concentration range used in this study. Transfection efficiency To test the gene transfection potential of the HAp nanoparticle

• associated with the HAp nanoparticle in HL-1 cells using specific pharmacological inhibitors. Endocytic pathways are divided into clathrin-mediated endocytosis, caveolae-mediated endocytosis, and macropinocytosis. The pathways were analyzed by measuring the effect of the endocytosis inhibitors on the

• . Discussion The development of gene therapy is essential for generating new treatment options for cardiovascular disease. We focused on safe non-viral vectors using nanotechnology. Although nanoparticle-based gene-transfection methods have been proposed for gene delivery into target cells and tissues, there

Electrokinetic characterization of synthetic protein nanoparticles

• Daniel F. Quevedo,
• Cody J. Lentz,
• Adriana Coll de Peña,
• Yazmin Hernandez,
• Nahal Habibi,
• Rikako Miki,
• Joerg Lahann and
• Blanca H. Lapizco-Encinas

Beilstein J. Nanotechnol. 2020, 11, 1556–1567, doi:10.3762/bjnano.11.138

• Microscale Bioseparations Laboratory and Biomedical Engineering Department, Rochester Institute of Technology, Rochester NY, USA Chemical Engineering, University of Michigan - Ann Arbor, Ann Arbor MI, USA 10.3762/bjnano.11.138 Abstract The application of nanoparticle in medicine is promising for the

• , non-small cell lung cancer, and pancreatic adenocarcinomas [9]. Current technologies allow for the synthesis of smart PNPs that release their active enzymatic load into oxidative environments [6]. A next step to further advance smart protein nanoparticle technologies is to develop a scalable method

• condition for the electrokinetic trapping of microorganisms in arrays of insulating posts, as well as to determine the empirical EP of the second-kind mobility by employing Equation 9 with eEEEC. The parameters of eEEEC and are reported in Table 2 for all the PNPs studied here. Experimental Nanoparticle

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

• through UV–vis absorption of 4-NPh. Likewise, it was shown that the surface basicity increases with decreasing nanoparticle size. The presence of CuCO3 on the surface of Cu2O, identified using X-ray photoelectron spectroscopy (XPS), passivates its surface and consequently diminishes the degradation of MP

• nanoparticle size, this is best explained by the small crystallite size of the NPs. An approximate size of the NPs can be calculated through measurements of this broadening [36]. Using the Scherrer equation, the three NPs sizes obtained were 16 ± 3 nm (yellow powder), 29 ± 3 nm (orange powder), and 45 ± 9 nm

• nanoparticle of 16 nm, used in the degradation of MP. Figure 3b shows the FFT from the area marked with a yellow square in Figure 3a. The processed image in Figure 3c was obtained from the same area. Interplanar distances corresponded to the (211) and (110) planes of Cu2O, Figure 3c shows only the (110) plane

Optically and electrically driven nanoantennas

• Monika Fleischer,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2020, 11, 1542–1545, doi:10.3762/bjnano.11.136

• deposition [41], or on dense silver island films created by pulsed laser deposition [42] or physical vapor deposition [43]. In [44], individual plasmonic nanotags are prepared by coating gold nanoparticle clusters with Raman reporters. This work explores the minimum number of tags required for obtaining a

• to a sharp tip is refined to a two-step procedure with high throughput. A self-assembly approach to create a dumbbell antenna consisting of a 40 nm and an 80 nm Au nanoparticle at a scanning tip is shown in [48] and applied for single molecule sensitivity imaging. The advantage of applying TERS for

• sizeable third-harmonic generation from the pillar. The fact that nonlinear effects can already be observed in the absorption and scattering of single gold nanoparticles at much lower laser intensities is demonstrated in [56]. Using the so-called x-scan technique, a nanoparticle is scanned through a