Ferromagnetic resonance spectra of linear magnetosome chains

• Elizaveta M. Gubanova and
• Nikolai A. Usov

Beilstein J. Nanotechnol. 2024, 15, 157–167, doi:10.3762/bjnano.15.15

• of magnetic nanoparticle assemblies are often characterized by measuring ferromagnetic resonance (FMR) spectra [14][15]. The analysis of FMR spectra makes it possible to determine the effective magnetic field in the sample under study, which depends on the particle saturation magnetization, the type

• magnetic nanoparticle assemblies can be carried out by solving the stochastic Landau–Lifshitz equation [29][30][31][32][33][34][35]. This approach makes it possible, when calculating the FMR spectra, to take into account all the details of the geometric structure of magnetosome chains, the influence of

Specific absorption rate of randomly oriented magnetic nanoparticles in a static magnetic field

• Ruslan A. Rytov and
• Nikolai A. Usov

Beilstein J. Nanotechnol. 2023, 14, 485–493, doi:10.3762/bjnano.14.39

• of the field-free point is obtained for assemblies with different nanoparticle size distributions. The results obtained seem to be helpful for the development of a promising joint application of magnetic nanoparticle imaging and magnetic hyperthermia. Keywords: dynamic hysteresis loop; magnetic

A new method for obtaining the magnetic shape anisotropy directly from electron tomography images

• Cristian Radu,
• Ioana D. Vlaicu and
• Andrei C. Kuncser

Beilstein J. Nanotechnol. 2022, 13, 590–598, doi:10.3762/bjnano.13.51

• Cristian Radu Ioana D. Vlaicu Andrei C. Kuncser National Institute of Materials Physics, Magurele, Romania Faculty of Physics, University of Bucharest, Bucharest, Romania 10.3762/bjnano.13.51 Abstract A new methodology to obtain magnetic information on magnetic nanoparticle (MNP) systems via

• statistical information offers a valuable insight on any MNP system and, to the knowledge of the authors, there is no other technique capable of providing it. While the proposed methodology and associated software is able to provide statistical anisotropy information, its applicability goes beyond magnetic

• nanoparticle systems. In fact, regardless of the magnetic shape anisotropy, the output information regarding nanoparticle position, volume, and/or shape (via ellipsoid fitting) might be useful in other situations involving physical systems composed of more or less dispersed entities, including porous systems

Heating ability of elongated magnetic nanoparticles

• Elizaveta M. Gubanova,
• Nikolai A. Usov and
• Vladimir A. Oleinikov

Beilstein J. Nanotechnol. 2021, 12, 1404–1412, doi:10.3762/bjnano.12.104

• of magnitude with an increase in the volume fraction of nanoparticles in a cluster in the range of 0.04–0.2. Keywords: elongated magnetic nanoparticles; magnetic hyperthermia; numerical simulation; specific absorption rate; Introduction Magnetic nanoparticle assemblies have great potential for the

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

• relaxation time; nanoparticle coating; numerical simulation; stochastic Langevin dynamics method; superparamagnetic nanoparticles; Introduction One of the most important biomedical applications of colloidal magnetic nanoparticle systems is magnetic hyperthermia applied as an alternative for cancer treatment

• to average Néel and effective magnetic relaxation times can be explained by the competition between the repulsion and attraction forces acting on the nanoparticles. The results presented here have the potential to be applied in several fields that use colloidal magnetic nanoparticle systems, in

• the hyperthermia efficiency [17], while others do not suggest a correlation between the coating layer thickness and the magnetic hyperthermia properties (i.e., the absorption rate) [18]. These issues demonstrate the importance of investigating the ways in which the coating influences magnetic

Dynamics of superparamagnetic nanoparticles in viscous liquids in rotating magnetic fields

• Nikolai A. Usov,
• Ruslan A. Rytov and
• Vasiliy A. Bautin

Beilstein J. Nanotechnol. 2019, 10, 2294–2303, doi:10.3762/bjnano.10.221

• (AMF) of frequency f = 100–500 kHz and amplitude H0 = 100–200 Oe. This would allow the tumor temperature to be maintained at about 42 °C if a magnetic nanoparticle assembly were capable to absorb efficiently the energy of the alternating magnetic field. According to a number of medical indications [1

• rotates in the XY-plane of the Cartesian coordinates, so that Neglecting weak magnetic damping and a small moment of inertia of a magnetic nanoparticle, the magneto-dynamic equations of motion of the unit vectors and in a viscous fluid have the form [25] where G = K/3η, η is the liquid viscosity, K is

• calculated by solving the stochastic Equations 4–7 and averaging the results over a sufficiently large number of independent numerical experiments carried out for the same magnetic nanoparticle under arbitrary initial conditions. First of all, it is interesting to compare the results of the SAR calculation

Magnetic field-assisted assembly of iron oxide mesocrystals: a matter of nanoparticle shape and magnetic anisotropy

• Julian J. Brunner,
• Marina Krumova,
• Helmut Cölfen and
• Elena V. Sturm (née Rosseeva)

Beilstein J. Nanotechnol. 2019, 10, 894–900, doi:10.3762/bjnano.10.90

• possible by defined balancing of spatial and magnetic nanoparticle interactions. The formation of superstructures of superparamagnetic nanoparticles using a magnetic field is, therefore, a highly interesting approach to form tailor-made materials with outstanding anisotropic structures, morphologies and

Heating ability of magnetic nanoparticles with cubic and combined anisotropy

• Nikolai A. Usov,
• Mikhail S. Nesmeyanov,
• Elizaveta M. Gubanova and
• Natalia B. Epshtein

Beilstein J. Nanotechnol. 2019, 10, 305–314, doi:10.3762/bjnano.10.29

• . However, the ability of magnetic nanoparticle assemblies to generate heat can be improved if the nanoparticles are covered by nonmagnetic shells of appreciable thickness. Keywords: fractal clusters; magnetite nanoparticles; magneto–dipole interaction; numerical simulation; specific absorption rate

• nanoparticles in biological media to quantitatively predict their heating efficiency in magnetic nanoparticle hyperthermia. In this respect we would like to stress that the behavior of an assembly of magnetic nanoparticles in viscous liquids and biological media is different [2][3]. It has been proved recently

• = 50–100 Oe, at a typical frequency f = 300 kHz. This shows the substantial potential of these nanoparticles for application in magnetic nanoparticle hyperthermia. Numerical Simulation It has been recently shown [22] that the technique based on the stochastic LL equation is preferable for investigation

Droplet-based synthesis of homogeneous magnetic iron oxide nanoparticles

• Christian D. Ahrberg,
• Ji Wook Choi and
• Bong Geun Chung

Beilstein J. Nanotechnol. 2018, 9, 2413–2420, doi:10.3762/bjnano.9.226

• ,B), and TEM images of two independent particle syntheses in droplet reactors (C,D). Histograms of magnetic nanoparticle size of particles synthesized in batch (A), and in droplets (B) under the same conditions. Overlay of the two particle distributions (C). Bar diagram showing the reproducibility of

Field-controlled ultrafast magnetization dynamics in two-dimensional nanoscale ferromagnetic antidot arrays

• Anulekha De,
• Sucheta Mondal,
• Sourav Sahoo,
• Saswati Barman,
• Yoshichika Otani,
• Rajib Kumar Mitra and
• Anjan Barman

Beilstein J. Nanotechnol. 2018, 9, 1123–1134, doi:10.3762/bjnano.9.104

• , effective media for SW propagation due to the larger propagation velocity (steeper dispersion) than nanodot lattices. They find potential applications in magneto-photonic crystals [9], ultrahigh density data storage media [10], frequency-based magnetic nanoparticle detectors [11], waveguides for SWs [12][13

Enzymatically promoted release of organic molecules linked to magnetic nanoparticles

• Chiara Lambruschini,
• Silvia Villa,
• Luca Banfi,
• Fabio Canepa,
• Fabio Morana,
• Annalisa Relini,
• Paola Riani,
• Renata Riva and
• Fulvio Silvetti

Beilstein J. Nanotechnol. 2018, 9, 986–999, doi:10.3762/bjnano.9.92

• magnetic nanoparticle) would be directed to the tumour site, but the drug is released only when the overexpressed enzyme is present, becoming active. However, while conjugation of enzymes onto nanoparticles (including magnetic NPs) has been often studied [11][12][13][14][15] (proving that the enzymatic

• decided not to bind a real drug, but simply a fluorescent molecule, in order to facilitate analysis of enzymatic cleavage and obtain the first proof of concept of the enzymatic release of a small organic molecule bound to a magnetic nanoparticle. Results and Discussion Magnetite nanoparticles were

• . Conclusion We have successfully demonstrated the possibility to exploit a selective protease-mediated release of an organic molecule from a magnetic nanoparticle. Although in this preliminary investigation the released molecule was only a simple fluorescent substance (pyrenylmethylamine), the same strategy

Methods for preparing polymer-decorated single exchange-biased magnetic nanoparticles for application in flexible polymer-based films

• Laurence Ourry,
• Delphine Toulemon,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2017, 8, 408–417, doi:10.3762/bjnano.8.43

• resulting nanohybrids can be considered as valuable building blocks for flexible, magnetic polymer-based devices. Keywords: assembly; ATRP; magnetic nanoparticle; exchange-bias; films; functionalization; polymerization; poly(methyl methacrylate); polystyrene; seed-mediated growth; surface; Introduction

A novel electrochemical nanobiosensor for the ultrasensitive and specific detection of femtomolar-level gastric cancer biomarker miRNA-106a

• Maryam Daneshpour,
• Kobra Omidfar and
• Hossein Ghanbarian

Beilstein J. Nanotechnol. 2016, 7, 2023–2036, doi:10.3762/bjnano.7.193

• pretreatment or amplification. Consequently, our biosensing strategy offers such a promising application to be used for clinical early detection of GC and additionally the screen of any miRNA sequence. Keywords: electrochemical nanobiosensor; gastric cancer; gold–magnetic nanoparticle; miR-106a; Introduction

Hemolysin coregulated protein 1 as a molecular gluing unit for the assembly of nanoparticle hybrid structures

• Tuan Anh Pham,
• Andreas Schreiber,
• Elena V. Sturm (née Rosseeva),
• Stefan Schiller and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2016, 7, 351–363, doi:10.3762/bjnano.7.32

• the larger size, this catalyst can be easily recycled by centrifugation or even by filtration compared to the pure Au NPs. This makes the hybrid structure more attractive as a catalyst with comparable reactivity. Magnetic nanoparticle assembly In this work, the concept of NP network formation using

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

• applications in biomedicine, in particular for hyperthermia-based treatments. Recent medical researches show that the heat generation of iron oxide nanoparticles in an alternating magnetic field activates an immune system response to tumors [1]. In magnetic nanoparticle systems for hyperthermia applications

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

• . The interaction of nanoparticles with cell membranes, their ingestion by cells, and their intracellular storage may have negative effects on the cells, regardless of the toxicity of the particles and their subsequent functionality. Numerous studies have reported magnetic-nanoparticle-induced cell

Designing magnetic superlattices that are composed of single domain nanomagnets

• Derek M. Forrester,
• Feodor V. Kusmartsev and
• Endre Kovács

Beilstein J. Nanotechnol. 2014, 5, 956–963, doi:10.3762/bjnano.5.109

• general conclusion of these papers was that a mean-field treatment is not adequate to study magnetic nanoparticle systems [10][11][12][13]. Therefore, in the present paper we developed a microscopic approach which is based on considering the dynamical behavior of magnetic nanoparticles with the use of

Manipulation of isolated brain nerve terminals by an external magnetic field using D-mannose-coated γ-Fe₂O₃ nano-sized particles and assessment of their effects on glutamate transport

• Tatiana Borisova,
• Natalia Krisanova,
• Arsenii Borуsov,
• Roman Sivko,
• Ludmila Ostapchenko,
• Michal Babic and
• Daniel Horak

Beilstein J. Nanotechnol. 2014, 5, 778–788, doi:10.3762/bjnano.5.90

• methodological approaches for the manipulation of nerve cells by an external magnetic field can open new possibilities in disorder treatment. Methods based on the remote manipulation of magnetic nanoparticle-labeled cells by magnetic fields are receiving a great attention essentially because magnetic fields are

Plasma-assisted synthesis and high-resolution characterization of anisotropic elemental and bimetallic core–shell magnetic nanoparticles

• M. Hennes,
• A. Lotnyk and
• S. G. Mayr

Beilstein J. Nanotechnol. 2014, 5, 466–475, doi:10.3762/bjnano.5.54

• heterostructured NP in gas condensation processes are discussed. Keywords: bimetallic magnetic nanoparticle; core–shell; magnetron sputtering; plasma gas condensation; Introduction Due to their size, novel physical properties and the possibility of contactless manipulation, magnetic nanoparticles can be employed

Hydrogen-plasma-induced magnetocrystalline anisotropy ordering in self-assembled magnetic nanoparticle monolayers

• Alexander Weddemann,
• Judith Meyer,
• Anna Regtmeier,
• Irina Janzen,
• Dieter Akemeier and
• Andreas Hütten

Beilstein J. Nanotechnol. 2013, 4, 164–172, doi:10.3762/bjnano.4.16

Magnetic-Fe/Fe₃O₄-nanoparticle-bound SN38 as carboxylesterase-cleavable prodrug for the delivery to tumors within monocytes/macrophages

• Hongwang Wang,
• Tej B. Shrestha,
• Matthew T. Basel,
• Raj K. Dani,
• Gwi-Moon Seo,
• Sivasai Balivada,
• Marla M. Pyle,
• Heidy Prock,
• Olga B. Koper,
• Prem S. Thapa,
• David Moore,
• Ping Li,
• Viktor Chikan,
• Deryl L. Troyer and
• Stefan H. Bossmann

Beilstein J. Nanotechnol. 2012, 3, 444–455, doi:10.3762/bjnano.3.51

• SN38 tethered on the surface of Fe/Fe3O4 magnetic nanoparticles, indicating the close proximity of SN38 to the magnetic nanoparticle. We also performed UV–vis characterization of the MNP-SN38 in PBS solution, but the absorption of SN38 was not observed due to overlapping with the broad MNP absorption

Magnetic nanoparticles for biomedical NMR-based diagnostics

• Huilin Shao,
• Tae-Jong Yoon,
• Monty Liong,
• Ralph Weissleder and
• Hakho Lee

Beilstein J. Nanotechnol. 2010, 1, 142–154, doi:10.3762/bjnano.1.17

• more effective magnetic nanoparticle biosensors, DMR detection limits for various target moieties have been considerably improved over the last few years. Already, a library of magnetic nanoparticles has been developed, in which a wide range of targets, including DNA/mRNA, proteins, small molecules

• enabled parallel and sensitive measurements to be made from small volume samples. Thus, the DMR technology is a highly attractive platform for portable, low-cost, and efficient biomolecular detection within a biomedical setting. Keywords: biosensor; diagnostics; magnetic nanoparticle; microfluidics

Review and outlook: from single nanoparticles to self-assembled monolayers and granular GMR sensors

• Alexander Weddemann,
• Inga Ennen,
• Anna Regtmeier,
• Camelia Albon,
• Annalena Wolff,
• Katrin Eckstädt,
• Nadine Mill,
• Michael K.-H. Peter,
• Jochen Mattay,
• Carolin Plattner,
• Norbert Sewald and
• Andreas Hütten

Beilstein J. Nanotechnol. 2010, 1, 75–93, doi:10.3762/bjnano.1.10

• within the vesicles is controlled by an oxidation–reduction system. Nucleation: Several proteins are believed to regulate the morphology. Mms5, Mms6, Mms7 and Mm13 are tightly bound to the magnetic nanoparticle. All these proteins are amphiphilic. Their N-terminal is hydrophilic while their C-terminal is

• has reached an equilibrium state, remagnetization processes along the assembly become the dominating dynamics. Since small magnetic objects do not have an inner magnetic substructure but the magnetization is homogeneously distributed along the volume, the stray field at a point r of a magnetic

• nanoparticle with magnetic moment m situated in the origin is given by the dipolar expression [62] with ‹ • , • › the Euclidean inner product. A schematic representation is shown in Figure 12(a). Adjacent particles influence each other via their dipolar coupling. Strong interactions can be found in such