Tunable longitudinal modes in extended silver nanoparticle assemblies

• Serene S. Bayram,
• Klas Lindfors and
• Amy Szuchmacher Blum

Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113

• [37]. We can accomplish a similar effect using a simple room-temperature process in aqueous solution, using ligand interactions to tune the optical properties of spherical nanoparticles through self-assembly. In our assemblies, the close proximity of AgNPs alongside with chain length modulation

Multiwalled carbon nanotube hybrids as MRI contrast agents

• Nikodem Kuźnik and
• Mateusz M. Tomczyk

Beilstein J. Nanotechnol. 2016, 7, 1086–1103, doi:10.3762/bjnano.7.102

• . Nevertheless, there is an experimental and theoretical approach to fill this gap. Koenig managed to derive T1 and T2 relaxation time functions for nanoparticles within a broad range of the magnetic field [55]. This theory applies to spherical nanoparticles with a cubic crystal unit, such as SPIO. However, the

Efficient electron-induced removal of oxalate ions and formation of copper nanoparticles from copper(II) oxalate precursor layers

• Kai Rückriem,
• Sarah Grotheer,
• Henning Vieker,
• Paul Penner,
• André Beyer,
• Armin Gölzhäuser and
• Petra Swiderek

Beilstein J. Nanotechnol. 2016, 7, 852–861, doi:10.3762/bjnano.7.77

• infrared spectroscopy (RAIRS). Helium ion microscopy (HIM) reveals the formation of spherical nanoparticles with well-defined size and X-ray photoelectron spectroscopy (XPS) confirms their metallic nature. Continued irradiation after depletion of oxalate does not lead to further particle growth giving

• the consequent formation of a nanoparticulate material is investigated here. HIM measurements of an irradiated sample of copper(II) oxalate produced by 16 deposition cycles reveals the formation of spherical nanoparticles with well-defined sizes. These particles consist of metallic copper according to

• copper(II) oxalate needles and become even more visible after an electron exposure of 8000 μC/cm2 (Figure 4d). After this exposure, most of the needle-like structures have disappeared pointing to the removal of copper(II) oxalate under electron exposure. Instead, the surface is now covered with spherical

Direct formation of gold nanorods on surfaces using polymer-immobilised gold seeds

• Majid K. Abyaneh,
• Pietro Parisse and
• Loredana Casalis

Beilstein J. Nanotechnol. 2016, 7, 809–816, doi:10.3762/bjnano.7.72

• surface of P1-60 has remained unchanged with dispersed spherical nanoparticles. It is observed that GNRs are formed in a few small regions and agglomerated with larger particles as shown in Figure 5g. Figure 5h, Figure 5j and Figure 5k show how GNRs are formed on the surface of the P2-60 nanocomposite

Time-dependent growth of crystalline Au⁰-nanoparticles in cyanobacteria as self-reproducing bioreactors: 2. Anabaena cylindrica

• Liz M. Rösken,
• Felix Cappel,
• Susanne Körsten,
• Christian B. Fischer,
• Andreas Schönleber,
• Sander van Smaalen,
• Stefan Geimer,
• Christian Beresko,
• Georg Ankerhold and
• Stefan Wehner

Beilstein J. Nanotechnol. 2016, 7, 312–327, doi:10.3762/bjnano.7.30

• determine the area of each individual nanoparticle and to calculate, under the assumption of spherical nanoparticles, its diameter and volume. Since the relative error is decreasing with an increasing absolute number of pixels assigned to a nanoparticle in an image, significant values for the nanoparticles

• the electron dense background caused by the heavy metal stained biomass. Such tiny, nearly spherical nanoparticles have already a volume of more than 30 nm3 (1 nm3 crystalline gold contains around 60 gold atoms). From TEM images an average nanoparticle concentration inside the cells can be determined

Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure

• Martina Banchelli,
• Bruno Tiribilli,
• Roberto Pini,
• Luigi Dei,
• Paolo Matteini and
• Gabriella Caminati

Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2

• ] proposed to assemble silver nanoparticles to graphene oxide sheets employing electrostatic interactions and a polymer, as adhesive agent, to impart greater stability against aggregation of AgNPs. Previous investigations are generally focused on spherical nanoparticles and only recently Fan et al. reported

An adapted Coffey model for studying susceptibility losses in interacting magnetic nanoparticles

• Mihaela Osaci and
• Matteo Cacciola

Beilstein J. Nanotechnol. 2015, 6, 2173–2182, doi:10.3762/bjnano.6.223

• vectors of the magnetic moments of the nanoparticles i and j, respectively, and μ0 is the magnetic permeability of vacuum. Due to clinical limitations on the amplitude of the external magnetic field Hext [4][6][10], the anisotropy axes of the spherical nanoparticles are not perfectly aligned to the

• Numerical simulations We considered a system with spherical nanoparticles made of uncoated magnetite, with the following characteristics: density ρ = 5180 kg/m3 [3]; saturation magnetization Ms = 4.46·105 A/m [3]; uniaxial magnetic anisotropy with anisotropy constant Keff = 25·103 J/m3 [3]; random

Nanostructured superhydrophobic films synthesized by electrodeposition of fluorinated polyindoles

• Gabriela Ramos Chagas,
• Thierry Darmanin and
• Frédéric Guittard

Beilstein J. Nanotechnol. 2015, 6, 2078–2087, doi:10.3762/bjnano.6.212

• oleophobic properties are obtained due to the presence of spherical nanoparticles and low surface energy compounds. Keywords: bioinspiration; conducting polymers; electrochemistry; nanostructures; polyindoles; superhydrophobic; Introduction The number of studies about materials with superhydrophobic

• superhydrophobicity of PIndole-6-F6, for example. Here, the presence of a high amount of air between the droplet and the substrate can lead to extremely high θwater with a very low H. In the case of PIndole-6-F6, the presence of the spherical nanoparticles formed on the surface during the polymerization allows to

• properties were reached due to the presence of spherical nanoparticles and the fluorinated compounds on the surface. This work opens new ways in the formation of superhydrophobic polyindoles films by electrodeposition for future applications. Experimental Monomer synthesis and characterization 4-(aminomethyl

Synthesis, characterization and in vitro biocompatibility study of Au/TMC/Fe₃O₄ nanocomposites as a promising, nontoxic system for biomedical applications

• Hanieh Shirazi,
• Maryam Daneshpour,
• Soheila Kashanian and
• Kobra Omidfar

Beilstein J. Nanotechnol. 2015, 6, 1677–1689, doi:10.3762/bjnano.6.170

• nanocomposites are shown in Figure 7a,c. The darker, spherical nanoparticles (with a mean diameter of about 20 nm for Au/TMC/Fe3O4 nanoparticles and 40 nm for Au/chitosan/Fe3O4 nanoparticles) indicate successful attachment of Au nanoparticles onto the polymer-covered Fe3O4 nanoparticles. By comparison, it can be

Formation of substrate-based gold nanocage chains through dealloying with nitric acid

• Ziren Yan,
• Ying Wu and
• Junwei Di

Beilstein J. Nanotechnol. 2015, 6, 1362–1368, doi:10.3762/bjnano.6.140

• quasi-spherical nanoparticles [3]. During the replacement reaction, Au atoms are deposited epitaxially on the surface of the Ag template. They nucleate and grow into small islands, and eventually evolve into a shell around the silver particles. The thin shell formed in the early stage is incomplete, and

The Kirkendall effect and nanoscience: hollow nanospheres and nanotubes

• Abdel-Aziz El Mel,
• Ryusuke Nakamura and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 1348–1361, doi:10.3762/bjnano.6.139

• reports on this topic, similar to the case of the spherical nanoparticles presented in the previous section, the hollowing process of nanowires can now be easily described (Figure 9) [12][15][23][33][63][64][65][66][67][68][69][70][71]. Briefly, the conversion process starts with the adsorption of oxygen

Preparation of Ni/Cu composite nanowires

• Hu Wang,
• Xiaoyu Li,
• Ming Li,
• Kenan Xie and
• Li Liao

Beilstein J. Nanotechnol. 2015, 6, 1268–1271, doi:10.3762/bjnano.6.130

• mechanical stability of Ni/Cu composite nanowires and confirms that they are not merely a loose aggregate of spherical nanoparticles. The EDS graph of the synthesized Ni/Cu composite nanowires in a typical experiment is shown in Figure 1d. The analysis data show that the contents of nickel and copper were

Fulleropeptide esters as potential self-assembled antioxidants

• Mira S. Bjelaković,
• Tatjana J. Kop,
• Jelena Đorđević and
• Dragana R. Milić

Beilstein J. Nanotechnol. 2015, 6, 1065–1071, doi:10.3762/bjnano.6.107

• -assembled structures. Additionally, SEM images of self-organized structures of all the investigated compounds are shown in Figure S1 (Supporting Information File 1). Two types of rounded particles (flat and curled), originating from spontaneously formed, self-organized spherical nanoparticles, were the

• )). SEM studies revealed that the other five fulleropeptides, 4, 5, 9, 11, and 12, self-assembled into mainly individual, flat-spherical nanoparticles of various sizes (Figure 3C,D) or into the network-type structures (Figure 3E,F). It should be noted that the heteropeptides 9, 11, and 12 had the

• fulleropeptide spherical nanoparticles. Half-wave reduction potentials vs Fc/Fc+ (0.53 V vs Ag/Ag+ in DMF) of fullerene esters in DMF containing 0.1 M TBAP as the supporting electrolyte. The direct antioxidant capacity (Δ%) and the relative antioxidant capacity (Aox-rel) of the tested compounds (0.002 mg/mL

Nanostructuring of GeTiO amorphous films by pulsed laser irradiation

• Valentin S. Teodorescu,
• Cornel Ghica,
• Adrian V. Maraloiu,
• Mihai Vlaicu,
• Andrei Kuncser,
• Magdalena L. Ciurea,
• Ionel Stavarache,
• Ana M. Lepadatu,
• Nicu D. Scarisoreanu,
• Andreea Andrei,
• Valentin Ion and
• Maria Dinescu

Beilstein J. Nanotechnol. 2015, 6, 893–900, doi:10.3762/bjnano.6.92

• ), the wave relief disappears and an irregular structure of nanovoids appears in the surface layer. A closer look at the transformed surface layer (see Figure 3) reveals the formation of spherical nanoparticles and nanovoids. The formed nanovoids contribute to the small volume increase even at 15 mJ/cm2

• field induces the formation of the amorphous Ge spherical nanoparticles. The Ge nanoparticles formation can be explained only by assuming the fast diffusion of Ge in a surface layer with its thickness being related to the laser radiation absorption length. The laser pulse duration is τ = 7 ns, and the

Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

• Lisa Landgraf,
• Ines Müller,
• Peter Ernst,
• Miriam Schäfer,
• Christina Rosman,
• Isabel Schick,
• Oskar Köhler,
• Hartmut Oehring,
• Vladimir V. Breus,
• Thomas Basché,
• Carsten Sönnichsen,
• Wolfgang Tremel and
• Ingrid Hilger

Beilstein J. Nanotechnol. 2015, 6, 300–312, doi:10.3762/bjnano.6.28

• the cellular ATP levels than smaller ones. Nevertheless, these findings appear not to be specific for the asymmetric structure of the Au@MnO particles, as spherical nanoparticles exhibit a similar behavior (Figure 3b, 10 nm vs 24 nm MnO domain). This aspect has been corroborated by other studies on

• spherical nanoparticles demonstrating that larger nanoparticles exhibit a higher cytotoxic potential than smaller ones [50][51]. Therefore, the size-dependency rules already known for spherical nanoparticles also apply for particles with Janus features. Nanoparticle internalization depends on surface charge

Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

• Anja Ostrowski,
• Daniel Nordmeyer,
• Alexander Boreham,
• Cornelia Holzhausen,
• Lars Mundhenk,
• Christina Graf,
• Martina C. Meinke,
• Annika Vogt,
• Sabrina Hadam,
• Jürgen Lademann,
• Eckart Rühl,
• Ulrike Alexiev and
• Achim D. Gruber

Beilstein J. Nanotechnol. 2015, 6, 263–280, doi:10.3762/bjnano.6.25

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• with a prism or a grating, and from photonic structures, the most successful and promising results were certainly obtained from localized surface plasmon resonances in nanostructures. 4.3.1 Spherical nanoparticles: In 2009, Pluchery et al. and Humbert et al. demonstrated that the vibrational SFG

• detection of the bio-recognition and of a subsequent molecular re-ordering. 4.3.2 Nano-antennas: Up to now, SE-SFG has been demonstrated in only a few studies with a limited variety of nanostructures. Asides from spherical nanoparticles, the other reported nanostructure was nano-antennas. Supporting two

Properties of plasmonic arrays produced by pulsed-laser nanostructuring of thin Au films

• Katarzyna Grochowska,
• Katarzyna Siuzdak,
• Peter A. Atanasov,
• Carla Bittencourt,
• Anna Dikovska,
• Nikolay N. Nedyalkov and
• Gerard Śliwiński

Beilstein J. Nanotechnol. 2014, 5, 2102–2112, doi:10.3762/bjnano.5.219

• a Drude metal, the absorption cross section of spherical nanoparticles is given by [37]: where ω is the irradiation frequency, c is the speed of light, V is the particle volume and εm, ε1, ε2 are the dielectric constants of the medium, and the real and imaginary parts of the metal dielectric

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• extinction cross sections of aggregated structures [73]. This heating process is followed by a rapid cooling upon decay of the laser pulse after 10−6–10−4 s, leading to solidified spherical nanoparticles (Figure 3A) [72]. Based on this mechanism the available particle size may be controlled by the pulse

One pot synthesis of silver nanoparticles using a cyclodextrin containing polymer as reductant and stabilizer

• Arkadius Maciollek and
• Helmut Ritter

Beilstein J. Nanotechnol. 2014, 5, 380–385, doi:10.3762/bjnano.5.44

• acting as reductant and steric stabilizer. We have shown that silver nanoparticles can be prepared under mild conditions without using an external environmental and biological risky reducing agent, stabilizer or additionally energy. Spherical nanoparticles with different sizes have been prepared by

Structural, optical and photocatalytic properties of flower-like ZnO nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Neha Bhardwaj,
• Jaspal Singh,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2013, 4, 763–770, doi:10.3762/bjnano.4.87

• ) formation of ZnO spherical nanoparticles, (ii) oriented attachment of ZnO nanoparticles resulting in nanosheets, followed by (iii) self-assembly of nanosheets into flower-like ZnO structures. UV–vis absorption spectra showing temporal evolution of photocatalytic degradation of MB upon irradiation with sun

Plasticity of Cu nanoparticles: Dislocation-dendrite-induced strain hardening and a limit for displacive plasticity

• Antti Tolvanen and
• Karsten Albe

Beilstein J. Nanotechnol. 2013, 4, 173–179, doi:10.3762/bjnano.4.17

• the metal particle in equilibrium [18], and since during the contraction the interaction is repulsive, the exact functional form of this interaction is irrelevant, and such a simple model captures the essence of the process of a contracting carbon shell. Spherical nanoparticles were formed by cutting

Nanoparticles of novel organotin(IV) complexes bearing phosphoric triamide ligands

• Zahra Shariatinia,
• Ebadullah Asadi,
• Vahid Tavasolinasab and
• Khodayar Gholivand

Beilstein J. Nanotechnol. 2013, 4, 94–102, doi:10.3762/bjnano.4.11

• their related phosphoric triamide ligands 5, 6. The spherical nanoparticles of complexes 1–4 were obtained by ultrasonication with particle sizes of about 20–25 nm. Results and Discussion Spectroscopic study In this work, new organotin(IV) complexes 1–4 were synthesized from the reaction of SnClR3 with

• measured in the 1H NMR spectra of complexes 1 and 4. Using ultrasonication, spherical nanoparticles of complexes 1–4 were prepared, and their SEM micrographs indicate that the nanoparticle sizes are about 20–25 nm. The fluorescence spectra illustrate blue shifts for the λ(max) of emission and a decrease in

Manipulation of gold colloidal nanoparticles with atomic force microscopy in dynamic mode: influence of particle–substrate chemistry and morphology, and of operating conditions

• Samer Darwich,
• Karine Mougin,
• Akshata Rao,
• Enrico Gnecco,
• Shrisudersan Jayaraman and
• Hamidou Haidara

Beilstein J. Nanotechnol. 2011, 2, 85–98, doi:10.3762/bjnano.2.10

• . Finally, conclusions with discussions and future directions are given in the last paragraph. 1. Influence of size and shape of the particle A. Influence of the size of the spherical Au particle Sizes of gold spherical nanoparticles(NPs) were tuned from 5 nm up to 65 nm according to the synthesis procedure

• radius of the average cluster Rtot (different sizes move at different angles). Moreover, the modeling of the NPs trajectory addresses a relation between the frictional forces acting on spherical nanoparticles, and the trajectories predicted. This model can also be used to interpret the trajectory

Enhanced visible light photocatalysis through fast crystallization of zinc oxide nanorods

• Sunandan Baruah,
• Mohammad Abbas Mahmood,
• Myo Tay Zar Myint,
• Tanujjal Bora and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2010, 1, 14–20, doi:10.3762/bjnano.1.3

• using microwave irradiation. Results and Discussion The ZnO nanoparticles obtained through the sol–gel synthesis (see section Experimental) are shown in Figure 1a and Figure 1b as transmission electron microscopy (TEM) micrographs. The low-resolution TEM micrograph exhibits spherical nanoparticles with