Anchoring Fe₃O₄ nanoparticles in a reduced graphene oxide aerogel matrix via polydopamine coating

• Błażej Scheibe,
• Radosław Mrówczyński,
• Natalia Michalak,
• Karol Załęski,
• Michał Matczak,
• Mateusz Kempiński,
• Zuzanna Pietralik,
• Mikołaj Lewandowski,
• Stefan Jurga and
• Feliks Stobiecki

Beilstein J. Nanotechnol. 2018, 9, 591–601, doi:10.3762/bjnano.9.55

• ][34], gas sensors [18] or even nanoswitches/actuators [22]. The magnetic properties of hybrid aerogels are related to the presence of magnetic nanoparticles (MNPs) which can be in ferromagnetic or superparamagnetic state and are embedded in aerogel matrix. Iron oxide nanoparticles, such as magnetite

• , which is due to additional contribution of PDA to the sample volume [65]. The agglomeration of magnetic nanoparticles has a direct effect on any measurement performed on NPs when extracting quantitative parameters, such as, e.g., the magnetic moment value [66]. The interparticle distance affects the

• saturation magnetization of magnetic nanoparticles, as the strength of the magnetic moment interaction depends on the interparticle distance [67]. Therefore, the compression of nanoparticles in the c-rGO-PDA@Fe3O4 aerogel sample led to the increase of the saturation magnetization. Figure 7b presents ZFC and

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• alignment seems to be ideal, due to the weak magnetic properties of CNTs, it postulates a very strong magnetic field of ≥7 T. This is why samples are usually placed inside a very narrow tube of a magnetic superconductor. Assembling CNTs with magnetic nanoparticles (MNPs) or packing them with LC molecules

Dynamic behavior of nematic liquid crystal mixtures with quantum dots in electric fields

• Emil Petrescu,
• Cristina Cirtoaje and
• Octavian Danila

Beilstein J. Nanotechnol. 2018, 9, 399–406, doi:10.3762/bjnano.9.39

• well as science and engineering, requires improved technologies and new materials. Materials science provides great opportunities to these technologies by synthesizing new nanoparticles that can be mixed with liquid crystals: carbon nanotubes [1][2][3], graphene, magnetic nanoparticles [4][5], gold

Liquid-crystalline nanoarchitectures for tissue engineering

• Baeckkyoung Sung and
• Min-Ho Kim

Beilstein J. Nanotechnol. 2018, 9, 205–215, doi:10.3762/bjnano.9.22

• electronics during the last decades. Technological breakthroughs can be achieved by introducing stimuli-responsivity or intelligence into the conventional LC biomaterials [114]. Hybridization with functional nanomaterials (e.g., stimuli-sensitive polymers, magnetic nanoparticles, carbon nanotubes and graphene

Alternating current magnetic susceptibility of a ferronematic

• Natália Tomašovičová,
• Jozef Kováč,
• Veronika Gdovinová,
• Nándor Éber,
• Tibor Tóth-Katona,
• Jan Jadżyn and
• Peter Kopčanský

Beilstein J. Nanotechnol. 2017, 8, 2515–2520, doi:10.3762/bjnano.8.251

• phase [Tomašovičová, N. et al. Soft Matter 2016, 12, 5780–5786]. The effect has no analogue in the neat host liquid crystal. Here, we demonstrate that by doubling the concentration of the magnetic nanoparticles, the range of the dc bias magnetic field to which the ferronematic is sensitive without

• susceptibility anisotropy (χa ≈ 10−6) of liquid crystals. As a way of lowering the required applied magnetic field, doping liquid crystals with magnetic nanoparticles (MNPs) has been proposed [2]. The stable colloidal suspensions of MNPs in nematic LCs are now known as ferronematics (FNs). Following the first

• other (higher) value is induced by the application of a relatively small dc magnetic field Hdc. The magnitude Δχ′ of the sudden reduction in χ′ depends on Hdc, as shown in Figure 5. It saturates at approximately 500 Oe. The increment Δχ′ is evidently due to the presence of magnetic nanoparticles, since

Dynamic behavior of a nematic liquid crystal mixed with CoFe₂O₄ ferromagnetic nanoparticles in a magnetic field

• Emil Petrescu,
• Cristina Cirtoaje and
• Cristina Stan

Beilstein J. Nanotechnol. 2017, 8, 2467–2473, doi:10.3762/bjnano.8.246

• well known for their slowness. The theoretical model applied is in good agreement with experimental data and can be used to design magneto-optic devices consisting of LCs and magnetic nanoparticles . Schematic representation of a laser beam (λ = 632.8 nm) passing through a planar nematic cell placed

Methionine-mediated synthesis of magnetic nanoparticles and functionalization with gold quantum dots for theranostic applications

• Arūnas Jagminas,
• Agnė Mikalauskaitė,
• Vitalijus Karabanovas and
• Jūrate Vaičiūnienė

Beilstein J. Nanotechnol. 2017, 8, 1734–1741, doi:10.3762/bjnano.8.174

• spectroscopy, inductively coupled plasma mass spectroscopy (ICP-MS), and X-ray photoelectron spectroscopy (XPS) of as-formed CoFe2O4 NPs before and after decoration with gold QDs were applied. Keywords: functionalization; gold; magnetic nanoparticles; quantum dots; theranostics; Introduction In current

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

• unique properties of magnetic nanoparticles have led to diverse applications in the fields of magnetic data storage, catalysis, magnetic fluids, biosensors, drug delivery, and magnetic imaging [1][2][3][4][5][6]. Considerable efforts have been taken to tailor the magnetic properties to suit specific

• minimally absorbed by tissue chromophores and water [24]. Therefore, tunable plasmonic nanoparticles that can respond to NIR light and can be manipulated with a magnetic field hold great promise. Among various magnetic nanoparticles, cobalt nanoparticles have attracted much interest due to their strong

• magnetic properties and their greater stability toward oxidation compared to Ni- and Fe-based magnetic nanoparticles [23]. Notably, there have been a handful of studies on magneto-optical nanostructures consisting of cobalt coated with gold. Bao and co-workers synthesized magnetic Co–Au core–shell

Cationic PEGylated polycaprolactone nanoparticles carrying post-operation docetaxel for glioma treatment

• Cem Varan and
• Erem Bilensoy

Beilstein J. Nanotechnol. 2017, 8, 1446–1456, doi:10.3762/bjnano.8.144

• -time and also enhanced the concentration of BCNU in the brain tumor area [27]. In addition to drug delivery, core–shell nanoparticles such as magnetic nanoparticles [28], quantum dots [29], nanodiamonds [30], nanocrystals [31] and iron oxide nanoparticles [32] are studied as imaging and detection

Characterization of ferrite nanoparticles for preparation of biocomposites

• Urszula Klekotka,
• Magdalena Rogowska,
• Dariusz Satuła and
• Beata Kalska-Szostko

Beilstein J. Nanotechnol. 2017, 8, 1257–1265, doi:10.3762/bjnano.8.127

• ; magnetic nanoparticles; surface immobilization; trypsin; X-ray diffraction; Introduction Nanoparticles are important ingredients in the fabrication of biocomposites, and therefore, the surface functionalization of nanoparticles attracts great interest among scientists [1][2]. Tests that aim at the

• set of particles. In particular, noncovalent interactions are the most important in terms of biological aspects [5]. A drawback of applying magnetic nanoparticles is that they possess a strong tendency to agglomerate due to not only van der Waals or electrostatic forces but also magnetic interactions

• , optical, magnetic and structural characteristics of specific nanoparticles in one hierarchical structure [9]. In such systems, nanoparticles can be functionalized with various biomolecules through different linkage chemistry [10][11][12]. Nanocomposites based on magnetic nanoparticles have a huge

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

• Laurence Ourry Delphine Toulemon Souad Ammar Fayna Mammeri Université Paris Diderot, Sorbonne Paris Cité, CNRS UMR 7086 ITODYS, Case 7090, 5 rue Thomas Mann, Paris, France 10.3762/bjnano.8.43 Abstract Background: Magnetic nanoparticles (NPs) must not only be well-defined in composition, shape and

• previously [15]. Figure 8 presents the TEM images. Better-separated ENPs are recovered when oleic acid is used, and they are, consequently, more adapted for applications in flexible polymer devices. Assembly of PMMA-decorated magnetic nanoparticles Finally, we assembled PMMA-functionalized ENPs prepared by

• -SEM and JEOL-100-CX II TEM microscopes, operating at 5.0 and 100 kV, respectively. Polymer-decorated exchange-biased CoxFe3−xO4@CoO magnetic nanoparticles synthesis. XPS survey spectra of (a) ENP-PS-18, (b) ENP-PS-24. IR spectrum of ENP-PS-18 and those of free PS and ENPs functionalized by the ATRP

From iron coordination compounds to metal oxide nanoparticles

• Mihail Iacob,
• Carmen Racles,
• Codrin Tugui,
• George Stiubianu,
• Adrian Bele,
• Liviu Sacarescu,
• Daniel Timpu and
• Maria Cazacu

Beilstein J. Nanotechnol. 2016, 7, 2074–2087, doi:10.3762/bjnano.7.198

• determine the number of surface atoms, which is decisive for their properties. The surface of the nanoparticle increases with decreasing particle size and also depends on its geometry [7]. For a certain type of magnetic nanoparticles, their size and/or geometry define the magnetic transitions. For example

• , magnetite is ferromagnetic when the particle diameter is larger than 15 nm and superparamagnetic when smaller [8]. Zhen et al. demonstrate that cubic nanoparticles have higher saturation magnetization and T2 relaxation than spherical nanoparticles of the same size [9]. Magnetic nanoparticles with flat

Antitumor magnetic hyperthermia induced by RGD-functionalized Fe₃O₄ nanoparticles, in an experimental model of colorectal liver metastases

• Oihane K. Arriortua,
• Eneko Garaio,
• Borja Herrero de la Parte,
• Maite Insausti,
• Luis Lezama,
• Fernando Plazaola,
• Jose Angel García,
• Jesús M. Aizpurua,
• Maialen Sagartzazu,
• Mireia Irazola,
• Nestor Etxebarria,
• Ignacio García-Alonso,
• Alberto Saiz-López and
• José Javier Echevarria-Uraga

Beilstein J. Nanotechnol. 2016, 7, 1532–1542, doi:10.3762/bjnano.7.147

• the Basque Country, UPV/EHU, 20018 Donostia, Spain, Galdakao Usansolo Hospital, 48960 Bizkaia, Spain 10.3762/bjnano.7.147 Abstract This work reports important advances in the study of magnetic nanoparticles (MNPs) related to their application in different research fields such as magnetic hyperthermia

• metastases, where it is useful as a coadjuvant for either chemotherapy or radiotherapy as it increases sensitivity for tumor cells [7][8]. Magnetic nanoparticles (MNPs) injected directly into liver tumors have become an important platform in these treatments because the application of an alternating magnetic

• to the NPs. Infrared spectra of the magnetic nanoparticles have been performed in order to determine the type of ligands surrounding the magnetic nuclei (see Supporting Information File 1, Figure S2). In the case of oleic acid-coated Fe3O4@OA NPs, the –CH2 symmetric and asymmetric stretching

An efficient recyclable magnetic material for the selective removal of organic pollutants

• Clément Monteil,
• Nathalie Bar,
• Agnès Bee and
• Didier Villemin

Beilstein J. Nanotechnol. 2016, 7, 1447–1453, doi:10.3762/bjnano.7.136

• harsh conditions. Keywords: adsorption; magnetic nanoparticles; organic pollutants; phosphonated polyethylenimine; Introduction During the last decades, an increased emphasis was placed on the issue of diffuse contamination of water. Toxic metals and organic pollutants are significant sources of

• studied [7][8]. At the same time, the emergence of nanotechnologies has led to a new generation of organic/inorganic nanocomposites with embedded magnetic nanoparticles (NPs) [9][10][11][12][13]. The application of a simple magnetic field is sufficient to collect them, which fosters the development of low

• successfully tested on both [15]. In addition, they often adsorb a limited amount of contaminant, considerably lower than the capacity of activated charcoal. We report herein a new adsorption process for water remediation, based on partially phosphonated polyethylenimine (PEIP)-coated magnetic nanoparticles

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

• (FA) (FA-PEI/PSS/SPIO/oMWCNT#Yin). A reversed methodology was applied for the formation of two other hybrids, where the initially wrapped oMWCNT with polyelectrolytes was used to support magnetic nanoparticles. Chen published a magnetic-fluorescent model, EuGdLa/SiO2/PAH/MWCNT#Chen, which resulted

Signal enhancement in cantilever magnetometry based on a co-resonantly coupled sensor

• Julia Körner,
• Christopher F. Reiche,
• Thomas Gemming,
• Bernd Büchner,
• Gerald Gerlach and
• Thomas Mühl

Beilstein J. Nanotechnol. 2016, 7, 1033–1043, doi:10.3762/bjnano.7.96

• für Festkörperelektronik, Technische Universität Dresden, 01062 Dresden, Germany 10.3762/bjnano.7.96 Abstract Cantilever magnetometry is a measurement technique used to study magnetic nanoparticles. With decreasing sample size, the signal strength is significantly reduced, requiring advances of the

Improved biocompatibility and efficient labeling of neural stem cells with poly(L-lysine)-coated maghemite nanoparticles

• Igor M. Pongrac,
• Marina Dobrivojević,
• Lada Brkić Ahmed,
• Michal Babič,
• Miroslav Šlouf,
• Daniel Horák and
• Srećko Gajović

Beilstein J. Nanotechnol. 2016, 7, 926–936, doi:10.3762/bjnano.7.84

• follow the stem cells through their migration, distribution, proliferation and differentiation is an essential prerequisite to characterize the biology and behavior of stem cells, to design the therapeutic approaches and minimize possible side effects [8][9][10]. Magnetic nanoparticles are widely used to

Comparison of the interactions of daunorubicin in a free form and attached to single-walled carbon nanotubes with model lipid membranes

• Dorota Matyszewska

Beilstein J. Nanotechnol. 2016, 7, 524–532, doi:10.3762/bjnano.7.46

• fields. Such magnetic nanoparticles conjugated with DNR were reported to induce apoptosis of cancer cell lines [11][12]. Other examples of nanoparticles include titanium dioxide (TiO2) and gold nanoparticles (AuNPs) [13][14]. In the latter case the nanoparticles were also modified with aptamer – single

Case studies on the formation of chalcogenide self-assembled monolayers on surfaces and dissociative processes

• Yongfeng Tong,
• Tingming Jiang,
• Azzedine Bendounan,
• Makri Nimbegondi Kotresh Harish,
• Angelo Giglia,
• Stefan Kubsky,
• Fausto Sirotti,
• Luca Pasquali,
• Srinivasan Sampath and
• Vladimir A. Esaulov

Beilstein J. Nanotechnol. 2016, 7, 263–277, doi:10.3762/bjnano.7.24

• interaction with Ni(111). We looked at Ni, since amongst other uses it can be employed as an electrode material. Additionally, Ni nanoparticles [93][94][95][96][97] are an example of magnetic nanoparticles [95] that are useful as catalysts [96], in magnetic fluids, as well as for binding and even magnetic

Simultaneous cancer control and diagnosis with magnetic nanohybrid materials

• Reza Saadat and
• Franz Renz

Beilstein J. Nanotechnol. 2016, 7, 121–125, doi:10.3762/bjnano.7.14

• foreclosed. Thus the visual input of the MNP can give a first cautious estimation of a successful functionalization. Conclusion In conclusion, Ga-DOTA and [Fe(II)(Cl-bzimpy)2] complexes were synthesized and linked to magnetic nanoparticles. The linked MNP were analyzed with DLS and TG/DTA and showed a

• annihilation of a positron with an electron by a radiopharmaceutical called “tracer” which has been previously injected intravenously into the patient. A computer reconstructs then tomographic images of the tracer concentration so that sectional images can be conveyed [5]. By linking PET isotopes to magnetic

• nanoparticles (MNP) a sophisticated system with different applications can be achieved (Figure 1): The magnetism of the particles allows an all-time control of the nanopharmaceuticals position, a linker, connecting the nanoparticles to each other, enables a pH-controlled assembly/disassembly and the PET

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

• frequencies and amplitudes of external magnetic fields for biomedical applications, especially for tumor therapy by magnetic hyperthermia. Keywords: hyperthermia; magnetic nanoparticles; relaxation process; specific loss power; susceptibility losses; Introduction Magnetic nanoparticles are important for

• upper limit of 4.85·108 Am−1s−1 for the product of frequency and field strength per one hour of treatment [4]. The influence of the nanoparticle concentration is implicitly related to the magnetic dipolar interactions among the nanoparticles. In order to select an assembly of magnetic nanoparticles

• suitable for use in hyperthermia, it is of interest to establish the conditions providing a sufficiently high SLP in an alternating external magnetic field of moderate amplitude Hext and frequency f [5]. The latest researches suggest that the so-called “hard-magnetic nanoparticles” are a more reliable

Self-assembly mechanism of Ni nanowires prepared with an external magnetic field

• Xiaoyu Li,
• Hu Wang,
• Kenan Xie,
• Qin Long,
• Xuefei Lai and
• Li Liao

Beilstein J. Nanotechnol. 2015, 6, 2123–2128, doi:10.3762/bjnano.6.217

• the surface of the nickel nanowires as well. Interestingly, magnetic nanoparticles can be first prepared and then aligned into one-dimensional chain-like structures in ferrofluids under a magnetic field [32][33][34][35]. The self-assembly behavior is similar to the second stage of the above self

A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe₃O₄ magnetic and fluorescent nanocrystals

• Houcine Labiadh,
• Tahar Ben Chaabane,
• Romain Sibille,
• Lavinia Balan and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

• diodes [6][7] or solar cells [8]. Conventional QDs systems have a core/shell architecture. The shell, generally constituted of a wide band gap material such as ZnS, prevents degradation and preserves the optical properties [3][4]. Magnetic nanoparticles have many advantages, especially for biological

• based on the unique feature of magnetic nanoparticles to respond well to magnetic control. The combination of magnetic and optical properties in a single, nanostructured material has attracted increased attention because of the advantageous properties of such nanoparticles. Such fluorescent and magnetic

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

• . Moreover, the results of the MTT assay showed no significant cytotoxicity effect when the Au/TMC/Fe3O4 nanocomposites were applied in vitro. These TMC-containing magnetic nanoparticles are well-coated by Au nanoparticles and have good biocompatibility and can thus play the role of a platform or a label in

• various fields of application, especially the biomedical sciences and biosensors. Keywords: Au/polymer/Fe3O4 nanocomposites; Au nanoparticles; cell viability; magnetic nanoparticles; N-trimethyl chitosan; Introduction Nanotechnology is the science of the fabrication of novel materials, devices and

• as catalysis, electronics, photonics, sensors, microfluidic lateral flow devices, medical diagnosis, and related sciences [6][7][8][9][10]. One of the most important classes of metal nanoparticles are magnetic nanoparticles. Due to their unique properties, such as magnetic resonance momentum, super

Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

• Xiaoxing Ke,
• Carla Bittencourt and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2015, 6, 1541–1557, doi:10.3762/bjnano.6.158

• nanotechnology: as building blocks for nanoelectronics [64], for drug delivery in biomedicine [65], and as bio-imaging agents when decorated with magnetic nanoparticles [66], just to name a few. The investigation of the interfaces of nanohybrids is often crucial in optimizing their design toward eventual