The nanofluidic confinement apparatus: studying confinement-dependent nanoparticle behavior and diffusion

• Stefan Fringes,
• Felix Holzner and
• Armin W. Knoll

Beilstein J. Nanotechnol. 2018, 9, 301–310, doi:10.3762/bjnano.9.30

• (termed height) and the lateral diffusion of 60 nm, charged, Au nanospheres as a function of confinement between a glass surface and a polymer surface. Interferometric scattering detection provides an effective particle illumination time of less than 30 μs, which results in lateral and vertical position

• the motion of the particles along high-gap-distance paths. Keywords: Au nanospheres; confinement; nanofluidics; subdiffusion; Introduction A fundamental understanding of the motion of micrometer- and nanometer-scaled objects in nanofluidic confinement is important for many biological and technical

• parallel confining surfaces for samples of choice and a cover glass to be adjusted and measured with nanometer accuracy. First, we describe and characterize the system, and then demonstrate its utility by measuring the behavior of 60 nm charged Au nanospheres in confinement between a glass and a polymer

Al₂O₃/TiO₂ inverse opals from electrosprayed self-assembled templates

• Arnau Coll,
• Sandra Bermejo,
• David Hernández and
• Luís Castañer

Beilstein J. Nanotechnol. 2018, 9, 216–223, doi:10.3762/bjnano.9.23

• clarity. The electrospray process of a nanofluid containing polystyrene nanospheres is described in the Experimental section below. The second step, shown in Figure 1b, consists of the deposition of a thin, conformal layer of Al2O3 in an ALD reactor at 80 °C. Such a low deposition temperature preserves

The role of ligands in coinage-metal nanoparticles for electronics

• Ioannis Kanelidis and
• Tobias Kraus

Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263

• etched and cube-shaped nanostructures predominated [73]. Didecyldimethylammonium bromide (DDAB) (Figure 2) in a mixture of Cu(acac)2 with phenyl ether and oleylamine (Figure 2) that normally yields copper nanospheres led to the formation of copper nanorods. Apparently, DDAB stabilized the {111} facets of

Fabrication of CeO₂–MO_x (M = Cu, Co, Ni) composite yolk–shell nanospheres with enhanced catalytic properties for CO oxidation

• Ling Liu,
• Jingjing Shi,
• Hongxia Cao,
• Ruiyu Wang and
• Ziwu Liu

Beilstein J. Nanotechnol. 2017, 8, 2425–2437, doi:10.3762/bjnano.8.241

• , Xuzhou 221008, People’s Republic of China School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, People’s Republic of China 10.3762/bjnano.8.241 Abstract CeO2–MOx (M = Cu, Co, Ni) composite yolk–shell nanospheres with uniform size were fabricated by a

• general wet-chemical approach. It involved a non-equilibrium heat-treatment of Ce coordination polymer colloidal spheres (Ce-CPCSs) with a proper heating rate to produce CeO2 yolk–shell nanospheres, followed by a solvothermal treatment of as-synthesized CeO2 with M(CH3COO)2 in ethanol solution. During the

• solvothermal process, highly dispersed MOx species were decorated on the surface of CeO2 yolk–shell nanospheres to form CeO2–MOx composites. As a CO oxidation catalyst, the CeO2–MOx composite yolk–shell nanospheres showed strikingly higher catalytic activity than naked CeO2 due to the strong synergistic

Magnetic properties of optimized cobalt nanospheres grown by focused electron beam induced deposition (FEBID) on cantilever tips

• Soraya Sangiao,
• César Magén,
• Darius Mofakhami,
• Grégoire de Loubens and
• José María De Teresa

Beilstein J. Nanotechnol. 2017, 8, 2106–2115, doi:10.3762/bjnano.8.210

• work, we present a detailed investigation of the magnetic properties of cobalt nanospheres grown on cantilever tips by focused electron beam induced deposition (FEBID). The cantilevers are extremely soft and the cobalt nanospheres are optimized for magnetic resonance force microscopy (MRFM) experiments

• , which implies that the cobalt nanospheres must be as small as possible while bearing high saturation magnetization. It was found that the cobalt content and the corresponding saturation magnetization of the nanospheres decrease for nanosphere diameters less than 300 nm. Electron holography measurements

• nanospheres with a diameter of ≈200 nm, which present atomic cobalt content of ≈83 atom % and saturation magnetization of 106 A/m, around 70% of the bulk value. These results represent the first comprehensive investigation of the magnetic properties of cobalt nanospheres grown by FEBID for application in MRFM

Fabrication of carbon nanospheres by the pyrolysis of polyacrylonitrile–poly(methyl methacrylate) core–shell composite nanoparticles

• Dafu Wei,
• Youwei Zhang and
• Jinping Fu

Beilstein J. Nanotechnol. 2017, 8, 1897–1908, doi:10.3762/bjnano.8.190

• , College of Materials Science and Engineering, Donghua University, Shanghai 201620, China 10.3762/bjnano.8.190 Abstract Carbon nanospheres with a high Brunauer–Emmett–Teller (BET) specific surface area were fabricated via the pyrolysis of polyacrylonitrile–poly(methyl methacrylate) (PAN–PMMA) core–shell

• nanoparticles. Firstly, PAN–PMMA nanoparticles at high concentration and low surfactant content were controllably synthesized by a two-stage azobisisobutyronitrile (AIBN)-initiated semicontinuous emulsion polymerization. The carbon nanospheres were obtained after the PAN core domain was converted into carbon

• shells, and the surface of the obtained PAN–PMMA nanoparticles became smooth. The thick PMMA shell can inhibit the adhesion between carbon nanospheres caused by cyclization reactions during heat treatment. The carbon nanospheres with a diameter of 35–65 nm and a high BET specific surface area of 612.8 m2

Near-infrared-responsive, superparamagnetic Au@Co nanochains

• Varadee Vittur,
• Arati G. Kolhatkar,
• Shreya Shah,
• Irene Rusakova,
• Dmitri Litvinov and
• T. Randall Lee

Beilstein J. Nanotechnol. 2017, 8, 1680–1687, doi:10.3762/bjnano.8.168

• compound under hydrogen [26]. The particles showed extinction maxima at ca. 550 nm and ca. 720 nm. Liang et al. used Co nanoparticles as sacrificial templates to prepare hollow gold nanospheres [27]. The formation of these particles involved a redox-transmetalation process between the core and shell

• nanospheres in contrast to the chain-linked structures obtained using a magnetic stirrer. This control experiment indicates a likely interaction between the magnetic nanoparticles and the external magnetic field produced by the magnetic stirrer during the galvanic replacement reaction. We hypothesize that

• of K–gold solution, a plasmon resonance appeared as a strong peak at ca. 900 nm; importantly, the nanochains possess no extinction bands characteristic of either bare gold nanoparticles or pure gold nanochains [68][69][70]. As mentioned above, Au-coated hollow nanospheres using Co nanoparticles as a

Development of polycationic amphiphilic cyclodextrin nanoparticles for anticancer drug delivery

• Gamze Varan,
• Juan M. Benito,
• Carmen Ortiz Mellet and
• Erem Bilensoy

Beilstein J. Nanotechnol. 2017, 8, 1457–1468, doi:10.3762/bjnano.8.145

• [19][20][21][22]. In the literature, amphiphilic CDs were reported to spontaneously self-assemble in the form of nanospheres or nanocapsules and overcome haemolytic activity on blood cells for eventual injectable nanoparticulate drug delivery [23][24][25]. The aim of this study was to evaluate and

• cells [36]. In another study, a polycationic, amphiphilic, cyclodextrin derivative was used to prepare nanospheres and nanocapsules as drug delivery systems. When the results are compared with this study in terms of particle size, it can be concluded that the use of surfactant is linearly correlated

• nanospheres [24]. The in vitro release profile of PCX from CD nanoparticles was determined using the dialysis bag method with HPLC as detailed in the Experimental section. As seen in Figure 5, PCX release from PC βCDC6 exhibited a markedly slower release profile of up to 42 h compared with other formulations

Optical response of heterogeneous polymer layers containing silver nanostructures

• Miriam Carlberg,
• Florent Pourcin,
• Olivier Margeat,
• Judikaël Le Rouzo,
• Gérard Berginc,
• Rose-Marie Sauvage,
• Jörg Ackermann and
• Ludovic Escoubas

Beilstein J. Nanotechnol. 2017, 8, 1065–1072, doi:10.3762/bjnano.8.108

• properties. Thin film layers with inclusions of differently shaped nanoparticles, such as nanospheres and nanoprisms, and of different sizes, are optically characterized. The nanoparticles are produced by a simple chemical synthesis at room temperature in water. The plasmonic resonance peaks of the different

• the nanoparticles to complete the optical characterization. A simple analysis method is proposed to obtain the complex refractive index of nanospheres and nanoprisms in a polymer matrix. Keywords: nanoprisms; nanospheres; plasmonic nanoparticles; spectroscopic ellipsometry; thin film layers

• physical vapor deposition methods require high energy sources, such as lasers [16], whereas chemical synthesis produces, among other shapes, nanospheres and nanoprisms of different sizes in water at room temperature. Taking advantage of the size and shape versatility of this chemical synthesis, we aim to

Synthesis of coaxial nanotubes of polyaniline and poly(hydroxyethyl methacrylate) by oxidative/initiated chemical vapor deposition

• Alper Balkan,
• Efe Armagan and
• Gozde Ozaydin Ince

Beilstein J. Nanotechnol. 2017, 8, 872–882, doi:10.3762/bjnano.8.89

• applicable in different areas [7][8]. Among these, the conducting polymer (CP) nanostructures, such as nanowires, nanorods, nanotubes or nanospheres have been extensively studied through solution-based techniques, such as chemical polymerization [9][10][11] or electrochemical polymerization [12][13][14] for

Selective detection of Mg²⁺ ions via enhanced fluorescence emission using Au–DNA nanocomposites

• Tanushree Basu,
• Khyati Rana,
• Niranjan Das and
• Bonamali Pal

Beilstein J. Nanotechnol. 2017, 8, 762–771, doi:10.3762/bjnano.8.79

• (λmax varied from 524 to 637 nm) [18][19][20][21]. The sample AuNS-4 exhibited a maximum shift (λmax ≈ 15 nm) relative to other nanospheres as these larger sized particles exhibit more light scattering. The AuNS-1 sample resulted in a shift from 524 to 538 nm upon addition of DNA, while DNA does not

• spectrum, which corresponds to B-DNA. These observations were due to stacking interactions between the bases and the helical structure of DNA [26]. As shown in Figure 2a, upon addition of Au nanospheres (AuNS) to the DNA solution, the molar ellipticity decreased at approximately 220 nm and increased by

• nanospheres and nanorods Gold nanospheres (AuNSs) were prepared as reported previously [35]. Typically, 10 mM of HAuCl4·H2O (250 μL) and 10 mM of freshly prepared ice-cold NaBH4 (600 μL) solution were added to 10 mL CTAB (100 mM) with gentle mixing, and labeled as seed solution (Solution A). Further, the

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

• then the TiO2 NPs were wrapped by graphene. These hybrids have high potential for photocatalytic application [72]. Zhang et al. have reported graphene-encapsulated TiO2 nanospheres as efficient photocatalysts for the decomposition of rhodamine B with an efficiency up to 91% in 90 min, which is much

• higher than the efficiency of TiO2 nanospheres (65%) [97]. The graphene-based nanoarchitecture of TiO2 nanospindles [98], TiO2 nanorods [92] and TiO2 mesoporous [99] shows improved photocatalytic performance via structural optimisation of the architecture. Although most of the applications of graphene

Computing the T-matrix of a scattering object with multiple plane wave illuminations

• Martin Fruhnert,
• Ivan Fernandez-Corbaton,
• Vassilios Yannopapas and
• Carsten Rockstuhl

Beilstein J. Nanotechnol. 2017, 8, 614–626, doi:10.3762/bjnano.8.66

• experimental data for the dispersive permittivity of silver [43]. Such objects can be fabricated in large quantities by self assembly methods, e.g., by connecting commercially available metal nanospheres with a linker molecule [44]. We set N = 2, because the higher orders do not contribute notably. For general

Formation and shape-control of hierarchical cobalt nanostructures using quaternary ammonium salts in aqueous media

• Ruchi Deshmukh,
• Anurag Mehra and
• Rochish Thaokar

Beilstein J. Nanotechnol. 2017, 8, 494–505, doi:10.3762/bjnano.8.53

• , in this study, a wide range of nanostructures ranging from zero-dimensional nanospheres to hierarchical nanoplates and spindles have been successfully synthesized at ambient temperature in aqueous solution. The nanostructures reported here are formed by aggregation of spherical seed particles

• present work. In this study, we report the formation of various nanostructures of cobalt such as nanoplates, nanorods, nanospheres and nanospindles with well-defined crystal planes by performing an aqueous syntheses at ambient temperature. Various synthesis strategies have been used in the literature to

Self-assembly of silicon nanowires studied by advanced transmission electron microscopy

• Marta Agati,
• Guillaume Amiard,
• Vincent Le Borgne,
• Paola Castrucci,
• Richard Dolbec,
• Maurizio De Crescenzi,
• My Alì El Khakani and
• Simona Boninelli

Beilstein J. Nanotechnol. 2017, 8, 440–445, doi:10.3762/bjnano.8.47

• image, as reported in Figure 1a, the presence of both nanospheres (NSs) and nanowires (NWs) can be observed. Statistical analyses conducted on hundreds of nanostructures allowed us to estimate that the diameter of the NSs range from 50 to 500 nm, while the NW length varies from ≈100 nm up to ≈2–3 μm

Comparison of four methods for the biofunctionalization of gold nanorods by the introduction of sulfhydryl groups to antibodies

• Xuefeng Wang,
• Zhong Mei,
• Yanyan Wang and
• Liang Tang

Beilstein J. Nanotechnol. 2017, 8, 372–380, doi:10.3762/bjnano.8.39

• growth method as previously described [29]. Briefly, a seed solution of gold nanospheres (5–10 nm) was obtained by mixing HAuCl4 (5 mL, 0.5 mM) with (5 mL, 0.2 M) CTAB for 1 min, followed by the addition of (0.6 mL, 10 mM) fresh, ice-cold sodium borohydride under vigorous stirring. The seed solution was

Tailoring bifunctional hybrid organic–inorganic nanoadsorbents by the choice of functional layer composition probed by adsorption of Cu²⁺ ions

• Veronika V. Tomina,
• Inna V. Melnyk,
• Yuriy L. Zub,
• Aivaras Kareiva,
• Miroslava Vaclavikova,
• Gulaim A. Seisenbaeva and
• Vadim G. Kessler

Beilstein J. Nanotechnol. 2017, 8, 334–347, doi:10.3762/bjnano.8.36

• was optimized controlling the synthesis conditions, such as concentrations of reactants, basicity of the medium, and the process temperature. Keywords: copper(II) ions; methyl groups; N- and F-containing functional groups; silica nanospheres; sol–gel processes; sorption; surface chemistry

Nanoscale isoindigo-carriers: self-assembly and tunable properties

• Tatiana N. Pashirova,
• Andrei V. Bogdanov,
• Lenar I. Musin,
• Julia K. Voronina,
• Irek R. Nizameev,
• Marsil K. Kadirov,
• Vladimir F. Mironov,
• Lucia Ya. Zakharova,
• Shamil K. Latypov and
• Oleg G. Sinyashin

Beilstein J. Nanotechnol. 2017, 8, 313–324, doi:10.3762/bjnano.8.34

• , hyaluronic acid, and heparin, also amphiphilic prodrugs, and supramolecular hydrogels) [38][39][40]. One of the main strategies deals with the creation of self-assembled supramolecular structures with tunable morphologies (e.g., nanospheres, rods, nanofibers or nanotubes) adapted to the administration route

• and hydrogen bonding. Another strategy is the use of soft matter (micelles, emulsions, dendrimers, nanospheres, solid lipid nanoparticles or liposomes) as the delivery vehicle. These studies have been encouraged by the possibility to prevent side effects, to increase drug bioavailability, to decrease

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

• approximation (DDA) method [45]. A similar approach as the method used here has been earlier successfully used to model DNA-assembled nanospheres [46]. Extinction spectra of AgNPs modified by varying ratios of ligands: A) cysteamine, B) DTT and C) cysteine. Legend: r = number of ligand molecules/AgNP. Insets

The role of morphology and coupling of gold nanoparticles in optical breakdown during picosecond pulse exposures

• Yevgeniy R. Davletshin and
• J. Carl Kumaradas

Beilstein J. Nanotechnol. 2016, 7, 869–880, doi:10.3762/bjnano.7.79

• -dimensional assembly of particles affects the optical breakdown threshold of its surroundings. For this purpose we used a fully coupled electromagnetic, thermodynamic and plasma dynamics model for a laser pulse interaction with gold nanospheres, nanorods and assemblies, which was solved using the finite

• affected by the optical properties of the surrounding environment [3], the morphology of individual nanoparticle as well as the formation of nanoparticle assemblies [4][5]. Nanospheres and nanorods are the two most common shapes of gold nanoparticles. They can be made to assemble through binding to the

• resonance peaks of gold nanospheres towards the near infrared region. (This is useful in biological applications, where light has a good penetration depth) [5][16]. The use of plasmonic nanoparticles and the associated near-field enhancement has been used in applications based on the laser-induced breakdown

Surface coating affects behavior of metallic nanoparticles in a biological environment

• Darija Domazet Jurašin,
• Marija Ćurlin,
• Ivona Capjak,
• Tea Crnković,
• Marija Lovrić,
• Michal Babič,
• Daniel Horák,
• Ivana Vinković Vrček and
• Srećko Gajović

Beilstein J. Nanotechnol. 2016, 7, 246–262, doi:10.3762/bjnano.7.23

• TEM images provide evidence that no changes in the morphology or size of the CITAgNPs, PVPAgNPs and BSAAgNPs occurred upon dispersion in BM. Conversely, after being dispersed in the BM, all of the other studied NPs exhibited disordered and agglomerated morphologies (Figure 6). Small AgNP nanospheres

• nanodiscs, triangular nanoplates or nanospheres. In recent years, solution-phase methods developed rapidly toward a reproducible preparation of metallic NPs with controlled shape [66]. A typical synthesis of nanocrystals can be divided into three levels: nucleation, evolution of nuclei into seed, and growth

Evaluation of gas-sensing properties of ZnO nanostructures electrochemically doped with Au nanophases

• Elena Dilonardo,
• Michele Penza,
• Marco Alvisi,
• Cinzia Di Franco,
• Francesco Palmisano,
• Luisa Torsi and
• Nicola Cioffi

Beilstein J. Nanotechnol. 2016, 7, 22–31, doi:10.3762/bjnano.7.3

• . Comparing the pristine ZnO nanostructures annealed at the two different temperatures the responses of ZnO nanorods formed at 550 °C were higher than those of ZnO nanospheres obtained at 300 °C. Thus, the poor response of ZnO nanospheres compared to ZnO nanorods, although their surface area is higher, is

• possibly related to transducer function. Rai et al. [5] reported that the presence of a great number of grain boundaries in ZnO nanospheres acts as a highly resistive barrier, inducing the increase of the overall device resistance, since the electrical conductivity is equally influenced by the density and

• mobility of the charge carriers in the material. Moreover, the response times of pristine ZnO nanorods at different NO2 concentrations are lower compared to that of ZnO nanospheres, although their recovery times are higher, as reported in Table 2. H2S detection by means of ZnO nanostructures was

Green and energy-efficient methods for the production of metallic nanoparticles

• Mitra Naghdi,
• Mehrdad Taheran,
• Satinder K. Brar,
• M. Verma,
• R. Y. Surampalli and
• J. R. Valero

Beilstein J. Nanotechnol. 2015, 6, 2354–2376, doi:10.3762/bjnano.6.243

• into solution to synthesize Ag nanosheets. They claimed that the in situ generated Al(OH)3 influenced the formation of Ag nanosheets. The produced nanosheets in 60 min reaction had a thickness of 20–30 nm [111]. Sun and Li produced colloidal carbon micro and nanospheres from glucose in a hydrothermal

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

• the conversion chemistry of nanostructures from solid to hollow has reached a very advanced maturity, there is still much to be discovered and learned on this effect. Here, the recent progress on the use of the Kirkendall effect to synthesize hollow nanospheres and nanotubes is reviewed with a special

• emphasis on the fundamental mechanisms occurring during such a conversion process. The discussion includes the oxidation of metal nanostructures (i.e., nanospheres and nanowires), which is an important process involving the Kirkendall effect. For nanospheres, the symmetrical and the asymmetrical mechanisms

• conclude with a summary, where the prospective future direction of this research field is discussed. Keywords: hollow nanospheres; Kirkendall effect; metals; nanotubes; oxides; Review Introduction In the years following the discovery of the diffusion of gold in solid lead by Roberts-Austen in 1896 [1][2

Influence of the shape and surface oxidation in the magnetization reversal of thin iron nanowires grown by focused electron beam induced deposition

• Luis A. Rodríguez,
• Lorenz Deen,
• Rosa Córdoba,
• César Magén,
• Etienne Snoeck,
• Bert Koopmans and
• José M. De Teresa

Beilstein J. Nanotechnol. 2015, 6, 1319–1331, doi:10.3762/bjnano.6.136

• magnetic structures [19], the growth of three-dimensional nanowires [20][21] and the fabrication of nanospheres on scanning probe tips [22][23]. One of the crucial parameters to be controlled in such magnetic nanostructures grown by FEBID is the coercive field, HC, which corresponds to the magnetic field