Influence of the magnetic nanoparticle coating on the magnetic relaxation time

• Mihaela Osaci and
• Matteo Cacciola

Beilstein J. Nanotechnol. 2020, 11, 1207–1216, doi:10.3762/bjnano.11.105

• coefficient of dynamic viscosity, kB is the Boltzmann constant, and T is the temperature. After obtaining the effective magnetic relaxation time value of each nanoparticle, we can calculate the average effective magnetic relaxation time. The effective magnetic relaxation time is influenced by the magnetic

• , respectively, η is the dynamic viscosity coefficient, ri is the radius of the i-th nanoparticle, βi,tr(t) and βi,rot(t) are the random Brownian force and torque, respectively, Ii is the moment of inertia of the i-th nanoparticle, is the angular speed of the i-th nanoparticle, is the resultant of the

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• dynamic corrections modeled by the explicit dependence of the order parameter and the wave function renormalization factor on the Matsubara frequency. Based on the results of [67][79], the impact of static vertex corrections on the critical temperature can be estimated using the formula where is the

• critical temperature value calculated on the basis of the Allen–Dynes formula [80]. The input from the static part of the vertex corrections has the form A good measure of the dynamic vertex corrections is The results are summarized in Table 1. As one can see, the static part of the vertex corrections is

Thermophoretic tweezers for single nanoparticle manipulation

• Jošt Stergar and
• Natan Osterman

Beilstein J. Nanotechnol. 2020, 11, 1126–1133, doi:10.3762/bjnano.11.97

• technology, there is an incessant need, or at least a desire, for a (contactless) manipulation of small objects, such as nanoparticles, molecules, or even single atoms. In this work we present an approach to the thermophoretic trapping of particles in dynamic temperature gradients induced through laser

• , and the feedback loop frequency. The numerical simulation reproduced the experimental findings very well and can be thus utilized for the estimation of the stiffness for any combination of parameters. The all-optical creation of the tweezers allows for their dynamic relocation. Consequently, it

Vibration analysis and pull-in instability behavior in a multiwalled piezoelectric nanosensor with fluid flow conveyance

• Sayyid H. Hashemi Kachapi

Beilstein J. Nanotechnol. 2020, 11, 1072–1081, doi:10.3762/bjnano.11.92

• . investigated the effect of nonzero initial conditions, the nonlinear coefficient of squeeze film air damping, and the van der Waals effect on the stability of torsional nanomirrors for the obtained dynamic pull-in instability voltage using the size effect [14]. Fakhrabadi et al. utilized the modified couple

Highly sensitive detection of estradiol by a SERS sensor based on TiO₂ covered with gold nanoparticles

• Andrea Brognara,
• Ili F. Mohamad Ali Nasri,
• Beatrice R. Bricchi,
• Andrea Li Bassi,
• Caroline Gauchotte-Lindsay,
• Matteo Ghidelli and
• Nathalie Lidgi-Guigui

Beilstein J. Nanotechnol. 2020, 11, 1026–1035, doi:10.3762/bjnano.11.87

• -estradiol, an emerging contaminant in environmental waters. We have found a limit of detection of 1 nM with a sensitivity allowing for a dynamic range of five orders of magnitude (up to 100 µM). Keywords: aptamer; Au nanoparticles; 17-β estradiol (E2); plasmonics; sensor; surface-enhanced Raman scattering

• quantification is possible between 1 nM and 10 µM, i.e., the sensor has a dynamic range of at least four orders of magnitude. Conclusion TiO2 nanoporous surfaces covered with Au NPs were tested as SERS surfaces for the detection of 17β-estradiol. Different conditions of Au deposition were considered as they lead

• ) and has a wide dynamic range (up to 100 µM). These results combined with the fact that the sensor is all solid makes the nanopourous TiO2/Au systems interesting for environmental detection applications. Schematic of the SERS sensor. The figure is not to scale for the sake of clarity. SEM top-view

Gas-sensing features of nanostructured tellurium thin films

• Dumitru Tsiulyanu

Beilstein J. Nanotechnol. 2020, 11, 1010–1018, doi:10.3762/bjnano.11.85

• using a dc voltage supplier. In all measurements, the load resistance was chosen to be approximately one order of magnitude lower than the sample resistance. Figure 3 shows the dynamic response of both nanocrystalline (blue) and amorphous (black) nanostructured Te-based gas-sensitive devices to a

• . Normalized dynamic response of a microcrystalline (red), nanocrystalline (blue) and amorphous (black) nanostructured Te-based gas-sensitive device to a rectangular pulse of 1.0 ppm NO2 at room temperature (22 °C). Transient characteristics of gas-induced current in nanocrystalline Te films, at different

Wet-spinning of magneto-responsive helical chitosan microfibers

• Dorothea Brüggemann,
• Johanna Michel,
• Naiana Suter,
• Matheus Grande de Aguiar and
• Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

• the IOPs were homogeneously embedded as micrometer-sized agglomerates in the chitosan matrix (Figure 3B,C). Individual IOPs had a diameter of approximately 100 nm whereas their aggregates had a diameter on the order of several micrometers. According to the dynamic light scattering results (Table S2

• IOP dispersions in 1% acetic acid using a dynamic light scattering device (ZetaSizer NanoSP, Malvern, United Kingdom). Preparation of chitosan microfibers with IOPs A coagulation bath containing absolute ethanol (VWR, Darmstadt, Germany) was prepared in a polyethylene terephthalate glycol tube (MOCAP

Electrochemical nanostructuring of (111) oriented GaAs crystals: from porous structures to nanowires

• Elena I. Monaico,
• Eduard V. Monaico,
• Veaceslav V. Ursaki,
• Shashank Honnali,
• Vitalie Postolache,
• Karin Leistner,
• Kornelius Nielsch and
• Ion M. Tiginyanu

Beilstein J. Nanotechnol. 2020, 11, 966–975, doi:10.3762/bjnano.11.81

• suitable for the development of IR photodetectors with good sensitivity and dynamic characteristics. Experimental Electrochemical anodization. Crystalline 500 µm thick (111)-oriented substrates of Si-doped n-GaAs with a free electron concentration of 2 × 1018 cm−3 were used in this study. The samples were

Extracting viscoelastic material parameters using an atomic force microscope and static force spectroscopy

• Cameron H. Parvini,
• M. A. S. R. Saadi and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 922–937, doi:10.3762/bjnano.11.77

• requires a numerical convolution of U(t) and F(t) in terms of the material parameter set {Jg, Jn, τn}. Useful viscoelastic quantities When characterizing the response of viscoelastic materials to external stress, especially during cyclic loading (such as with dynamic mechanical analysis (DMA) machines), it

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

• Secil Öztürk,
• Yu-Xuan Xiao,
• Dennis Dietrich,
• Beatriz Giesen,
• Juri Barthel,
• Jie Ying,
• Xiao-Yu Yang and
• Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

• the CTF-1-400 materials is attributed to the better conductivity of the former (as obtained from the Nyquist plot in Figure 7). The half-wave potential of Ni/CTF-1-600-22 (0.775 V) was larger than that of CTF-1-600 (0.724 V) and that of Ni/CTF-1-600-33 (0.729 V), indicating a faster dynamic process

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• frequency-modulated atomic force microscopy (AFM). Furthermore, this technique can be extended to the experimental verification of potential forms for any given material pair. Specifically, interaction forces are determined between an AFM tip apex and a nominally flat substrate using dynamic force

• matching these F(z) curves to a set of LJ F(z) curves generated for the specific tip apex shape, as described in the following section. Determination of work and range of adhesion using in situ TEM adhesive experiments The method that will be discussed to determine LJ parameters from dynamic FM-AFM

Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach

• Edgar Cruz Valeriano,
• José Juan Gervacio Arciniega,
• Christian Iván Enriquez Flores,
• Susana Meraz Dávila,
• Joel Moreno Palmerin,
• Martín Adelaido Hernández Landaverde,
• Yuri Lizbeth Chipatecua Godoy,
• Aime Margarita Gutiérrez Peralta,
• Rafael Ramírez Bon and
• José Martín Yañez Limón

Beilstein J. Nanotechnol. 2020, 11, 703–716, doi:10.3762/bjnano.11.58

• (Figure 2). To show the capabilities of this technique, a graphite film was sputtered on a glass substrate and characterized by the proposed S-AFAM technique and by conventional RT-AFAM [7]. Mathematical Model Dynamic model In order to extract the resonance frequencies of a free cantilever and a

• observed dynamic behavior for a free AFM cantilever. Modeled values of klever. A BudgetSensors diamond-coated silicon cantilever with 450 μm length and a spring constant of 0.2 N/m was used in this experiment. Funding The work was supported by the Projects LIDTRA LN-295261 and LIDTRA LN2015-254119 of

Examination of the relationship between viscoelastic properties and the invasion of ovarian cancer cells by atomic force microscopy

• Mengdan Chen,
• Jinshu Zeng,
• Weiwei Ruan,
• Zhenghong Zhang,
• Yuhua Wang,
• Shusen Xie,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2020, 11, 568–582, doi:10.3762/bjnano.11.45

• properties of highly invasive cancer cells could be associated with a difference in the F-actin cytoskeleton [64][65]. Each of these tumorigenic transformation processes is regulated by the dynamic biomechanical behavior of the F-actin cytoskeleton within the examined ovarian cells, and the possible

Identification of physicochemical properties that modulate nanoparticle aggregation in blood

• Ludovica Soddu,
• Duong N. Trinh,
• Eimear Dunne,
• Dermot Kenny,
• Giorgia Bernardini,
• Ida Kokalari,
• Arianna Marucco,
• Marco P. Monopoli and
• Ivana Fenoglio

Beilstein J. Nanotechnol. 2020, 11, 550–567, doi:10.3762/bjnano.11.44

• at room temperature. In the case of SNPs, the samples were sputter-coated with a thick gold film (≈17 nm) under argon atmosphere to improve secondary electron emission during SEM imaging. The NPs morphology was observed at an acceleration voltage of 20 kV. Dynamic light scattering (DLS) The mean

• diameter and polydispersity index (PDI) of the NPs were obtained using a Zetasizer (Nano ZS Malvern Instruments, UK) instrument based on the dynamic light scattering (DLS) technique. The measurements were performed on purified NPs by analysing 0.5 mL of the suspension in ultrapure water, placed in a square

• . Dynamic platelet function assay (DPFA) The DPFA is a well-characterised real-time assay of platelet interaction with von Willebrand factor (VWF) under conditions of arterial shear [27][28][29]. The initial phases of platelet aggregation were assayed using the DPFA as previously described [25][26]. Briefly

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• /ethanol (90/10 v/v) mixture compared to that of in pure ethanol solution. In solution, the dynamic intramolecular rotation serves as a route for nonradiative relaxation process. Upon aggregation, the intramolecular rotations are restricted, which blocks the non-radiative pathways and opens the radiative

Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis

• Berkin Uluutku and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37

• contact-mode imaging. To explore its feasibility, we derive the analytical form of the tip–sample current that would be obtained for attractive (noncontact) and repulsive (intermittent-contact) dynamic AFM characterization, and compare it with results obtained from numerical simulations. Although

• dynamic current measurements, this manuscript discusses three different cases: (i) a noncontact dynamic current measurement where the cantilever follows an ideal sinusoidal trajectory, (ii) a similar case, but considering a more realistic trajectory where the tip oscillation is perturbed by the presence

• discussed in some cases, although some of these challenges are significant and have not yet been overcome. In the remainder of this section we will derive Fourier space expressions for the measured current for each case analysed. Case 1: Dynamic noncontact current measurement with ideal sinusoidal tip

Nanoparticles based on the zwitterionic pillar[5]arene and Ag⁺: synthesis, self-assembly and cytotoxicity in the human lung cancer cell line A549

• Dmitriy N. Shurpik,
• Denis A. Sevastyanov,
• Pavel V. Zelenikhin,
• Pavel L. Padnya,
• Vladimir G. Evtugyn,
• Yuriy N. Osin and
• Ivan I. Stoikov

Beilstein J. Nanotechnol. 2020, 11, 421–431, doi:10.3762/bjnano.11.33

• studied (Figure 1). The study of self-association of macrocycles 2–4 was carried out in water using the dynamic light scattering (DLS) method. It turned out that the decaamine 2, due to its poor solubility in water, does not form any self-associates across the entire range of concentrations studied (10−3

• out after mixing the solutions at 293 K. Dynamic light scattering (DLS) The particle size distribution formed as a result of self-association of the pillar[5]arenes 2–4 was determined at 20 °С by dynamic light scattering using a nanoparticle size analyzer (Zetasizer Nano ZS, Malvern) in quartz

High dynamic resistance elements based on a Josephson junction array

• Konstantin Yu. Arutyunov and
• Janne S. Lehtinen

Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32

• field, the low current bias dynamic resistance can reach values of ≈1011 Ω. It was demonstrated that the system can provide a decent quality current biasing circuit, enabling the observation of Coulomb blockade and Bloch oscillations in ultra-narrow Ti nanowires associated with the quantum phase-slip

• effect. Keywords: dynamic resistance; Josephson junction array; nanoelectronics; quantum phase slip; superconductivity; Ti nanowires; Introduction The field of modern nanoelectronics is facing stagnation with respect to further miniaturization, deviating from Moore’s law [1]. Typically, two main reason

• observation of a pronounced Coulomb blockade has been observed in JJs using both a high-resistive dissipative environment [7][8] and nonlinear Josephson elements with high dynamic resistance and/or kinetic inductance [6][18]. However, extended attempts to observe Bloch oscillation phenomena at finite currents

Brome mosaic virus-like particles as siRNA nanocarriers for biomedical purposes

• Alfredo Nuñez-Rivera,
• Pierrick G. J. Fournier,
• Danna L. Arellano,
• Ana G. Rodriguez-Hernandez,
• Rafael Vazquez-Duhalt and
• Ruben D. Cadena-Nava

Beilstein J. Nanotechnol. 2020, 11, 372–382, doi:10.3762/bjnano.11.28

• obtained by the addition of 6 μL of 1% uranyl acetate for 1 min. The size and zeta potential of the viral nanoparticles and VLPs were determined by dynamic light scattering (DLS) using a Malvern NanoSizer. The siRNA and the capsid protein were quantified from purified BMV VLP-siAkt1 using the Quant-it

Poly(1-vinylimidazole) polyplexes as novel therapeutic gene carriers for lung cancer therapy

• Gayathri Kandasamy,
• Elena N. Danilovtseva,
• Vadim V. Annenkov and
• Uma Maheswari Krishnan

Beilstein J. Nanotechnol. 2020, 11, 354–369, doi:10.3762/bjnano.11.26

• 100, Perkin Elmer, USA). Dynamic light scattering (DLS) and zeta potential measurements: The hydrodynamic size of the PVI–siRNA polyplexes was measured on a Zetasizer Nano ZS (Malvern instruments, UK). Samples at different volume ratios containing a final siRNA concentration of 100 nM were used for

• nanoparticles in the size range of 80 to 120 nm is clearly discernible from the electron micrographs. The hydrodynamic diameter of the blank PVI nanoparticles measured using dynamic light scattering was found to be about 237 ± 34.6 nm. The zeta potential measured for the blank PVI nanoparticles in HEPES buffer

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• macroscopic electrical characterization (Figure S3 in Supporting Information File 1) remains however below the state-of-the-art for PTB7:PC71BM-based devices. We will describe later that an imperfect morphology may be the origin of the reduced performance. In a first step, the dynamic photoresponse of the

• successive spectroscopic curves. In this configuration, the cathode defines an equipotential level. In other words, the dynamic SP photoresponse is not position-dependent. Furthermore, here, the SPV can be directly compared to the open-circuit voltage deduced from the macroscopic electrical characterization

Understanding nanoparticle flow with a new in vitro experimental and computational approach using hydrogel channels

• Armel Boutchuen,
• Dell Zimmerman,
• Abdollah Arabshahi,
• John Melnyczuk and
• Soubantika Palchoudhury

Beilstein J. Nanotechnol. 2020, 11, 296–309, doi:10.3762/bjnano.11.22

• the following equation: All measurements of weight and degree of swelling of the hydrogels were reported as an average of three swelling studies. Finally, the dynamic swelling behavior of different pHEMA hydrogels synthesized in this study were graphically summarized using 95% student’s t confidence

Using gold nanoparticles to detect single-nucleotide polymorphisms: toward liquid biopsy

• María Sanromán Iglesias and
• Marek Grzelczak

Beilstein J. Nanotechnol. 2020, 11, 263–284, doi:10.3762/bjnano.11.20

• particles relative to each other are restricted, which imposes a colorimetric transition, i.e., a blueshift or redshift of the localized surface plasmon resonance [138]. It is reasonable to assume that development of biosensors for liquid biopsy will benefit from growing research on dynamic self-assembly of

Rational design of block copolymer self-assemblies in photodynamic therapy

• Maxime Demazeau,
• Laure Gibot,
• Anne-Françoise Mingotaud,
• Patricia Vicendo,
• Clément Roux and
• Barbara Lonetti

Beilstein J. Nanotechnol. 2020, 11, 180–212, doi:10.3762/bjnano.11.15