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Magnetic Nanoparticles in Biological Applications
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Magnetic Nanoparticles in Biological Applications

A special issue of Nanomaterials (ISSN 2079-4991).

Deadline for manuscript submissions: closed (31 August 2018) | Viewed by 144665

Special Issue Editor

Dr. Olivier Sandre

E-Mail Website
Guest Editor
Laboratoire de Chimie des Polymères Organiques (LCPO), CNRS, Université de Bordeaux, Bordeaux-INP, Bordeaux, France
Interests: polymer nanoparticles; magnetic micelles and vesicles (polymersomes); contrast agents for MRI; theranostic nanovectors; magnetic field hyperthermia

Special Issue Information

Dear Colleagues,

Developed in the 1960s initially for technological applications, stable suspensions of magnetic nanoparticles (MNPs) also called “ferrofluids”, emerged during the 1990s as building blocks for biological applications: Contrast agents for MRI, bio-assays using magnetic separation, internal heat sources for thermo-ablation of tumors, drug carriers with magnetic guiding capability or targeted drug release activated by an applied magnetic field, etc. The research on novel biocompatible MNPs is very active and multidisciplinary, as it involves chemistry for the development of the MNP core and of their coatings, but also physics for the study and optimization of their magnetic properties, pharmacology when dealing with conjugation to biological ligands, drug encapsulation, drug release, etc. From the materials point of view, the chemical composition and crystalline structure of MNP cores can be varied among several transition metals, metal alloys or metal oxides. However, most MNPs aimed to be in contact with living cells or organisms are made of magnetic iron oxides, in order to minimize the risks of toxicity that can arise with other metals (manganese, cobalt, nickel, zinc, etc.). Alternatively, mixed spinels or pristine metals can be used to optimize the magnetic moments. However, they need to be coated with biocompatible shells to avoid ion leashing, either organic or inorganic, as in the development of magnetic core-shells, or even magnetic tri-shells (e.g., ferromagnetic-antiferromagnetic junctions to create exchange bias effects). Other magnetic carriers or magnetic devices are hybrid, i.e., they combine an organic matrix and magnetic nanofillers, creating multi-functional or multimodal probes for bio-imaging. One can cite MNPs combined with liposomes, polymer micelles or vesicles, protein or mesoporous silica shells. In particular, thermosensitive matrixes (polymer chains or gels with a thermal transition, inorganic porous shells filled with wax as gate keepers, etc.) were proposed to tune the drug release kinetics by applied magnetic fields. This Special Issue focuses on all aspects of new nanomaterials using MNPs as active components for biological applications (bio-assays, diagnosis and/or imaging probes, drug delivery systems, etc.), or on the interaction of MNPs with biological media (biological fluids, cell cultures, or living organisms). Studies which shed light on the cellular uptake of MNPs and on the intra-cellular magnetic hyperthermia mechanisms are particularly welcome. Special attention will also be paid to contributions from talented early-stage researchers who are settling their original approaches or new directions in this field of research.

Dr. Olivier Sandre
Guest Editor

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Keywords

  • bio-compatible magnetic nanoparticles
  • MRI contrast agents
  • magnetic bio-assays
  • magnetic nanoparticle hyperthermia
  • magnetically guided drug carriers
  • magnetic bio-actuators
  • magnetic tumor targeting
  • magnetically activated drug release
  • magnetic structure and properties
  • magnetic metals, alloys and metal oxides
  • magnetic core-shells
  • magnetic tri-shells
  • hybrid magnetic carriers
  • magnetic medical devices
  • magnetic responsive bio-nanocomposites
  • magnetic multi-modal bio-imaging probes
  • magnetic thermo-sensitive liposomes
  • magnetic polymer micelles or vesicles
  • magnetic protein capsules
  • magnetic core-mesoporous silica shells
  • magnetic thermo-sensitive polymers or gels
  • interaction of magnetic nanoparticles with biological media
  • magnetic nanoparticle cellular uptake
  • intracellular magnetic hyperthermia
  • pre-clinical assays on magnetic hyperthermia
  • magnetic nanoparticle therapies

Published Papers (27 papers)

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11 pages, 3243 KiB  
Article
Magnetofluorescent Nanocomposite Comprised of Carboxymethyl Dextran Coated Superparamagnetic Iron Oxide Nanoparticles and β-Diketon Coordinated Europium Complexes
by Daewon Han, Seung-Yun Han, Nam Seob Lee, Jongdae Shin, Young Gil Jeong, Hwan-Woo Park and Do Kyung Kim
Nanomaterials 2019, 9(1), 62; https://doi.org/10.3390/nano9010062 - 04 Jan 2019
Cited by 4 | Viewed by 3735
Abstract
Red emitting europium (III) complexes Eu(TFAAN)3(P(Oct)3)3 (TFAAN = 2-(4,4,4-Trifluoroacetoacetyl)naphthalene, P(Oct)3 = trioctylphosphine) chelated on carboxymethyl dextran coated superparamagnetic iron oxide nanoparticles (CMD-SPIONs) was synthesized and the step wise synthetic process was reported. All the excitation spectra of [...] Read more.
Red emitting europium (III) complexes Eu(TFAAN)3(P(Oct)3)3 (TFAAN = 2-(4,4,4-Trifluoroacetoacetyl)naphthalene, P(Oct)3 = trioctylphosphine) chelated on carboxymethyl dextran coated superparamagnetic iron oxide nanoparticles (CMD-SPIONs) was synthesized and the step wise synthetic process was reported. All the excitation spectra of distinctive photoluminesces were originated from f-f transition of EuIII with a strong red emission. The emission peaks are due to the hypersensitive transition 5D0→7F2 at 621 nm and 5D0→7F1 at 597 nm, 5D0→7F0 at 584 nm. No significant change in PL properties due to addition of CMD-SPIONs was observed. The cytotoxic effects of different concentrations and incubation times of Eu(TFAAN)3(P(Oct)3)3 chelated CMD-SPIONs were evaluated in HEK293T and HepG2 cells using the WST assay. The results imply that Eu(TFAAN)3(P(Oct)3)3 chelated CMD-SPIONs are not affecting the cell viability without altering the apoptosis and necrosis in the range of 10 to 240 μg/mL concentrations. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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18 pages, 2288 KiB  
Article
Magnetic Polyion Complex Micelles for Cell Toxicity Induced by Radiofrequency Magnetic Field Hyperthermia
by Vo Thu An Nguyen, Marie-Claire De Pauw-Gillet, Mario Gauthier and Olivier Sandre
Nanomaterials 2018, 8(12), 1014; https://doi.org/10.3390/nano8121014 - 06 Dec 2018
Cited by 10 | Viewed by 3058
Abstract
Magnetic nanoparticles (MNPs) of magnetite (Fe3O4) were prepared using a polystyrene-graft-poly(2-vinylpyridine) copolymer (denoted G0PS-g-P2VP or G1) as template. These MNPs were subjected to self-assembly with a poly(acrylic acid)-block-poly(2-hydroxyethyl acrylate) double-hydrophilic block copolymer (DHBC), [...] Read more.
Magnetic nanoparticles (MNPs) of magnetite (Fe3O4) were prepared using a polystyrene-graft-poly(2-vinylpyridine) copolymer (denoted G0PS-g-P2VP or G1) as template. These MNPs were subjected to self-assembly with a poly(acrylic acid)-block-poly(2-hydroxyethyl acrylate) double-hydrophilic block copolymer (DHBC), PAA-b-PHEA, to form water-dispersible magnetic polyion complex (MPIC) micelles. Large Fe3O4 crystallites were visualized by transmission electron microscopy (TEM) and magnetic suspensions of MPIC micelles exhibited improved colloidal stability in aqueous environments over a wide pH and ionic strength range. Biological cells incubated for 48 h with MPIC micelles at the highest concentration (1250 µg of Fe3O4 per mL) had a cell viability of 91%, as compared with 51% when incubated with bare (unprotected) MNPs. Cell internalization, visualized by confocal laser scanning microscopy (CLSM) and TEM, exhibited strong dependence on the MPIC micelle concentration and incubation time, as also evidenced by fluorescence-activated cell sorting (FACS). The usefulness of MPIC micelles for cellular radiofrequency magnetic field hyperthermia (MFH) was also confirmed, as the MPIC micelles showed a dual dose-dependent effect (concentration and duration of magnetic field exposure) on the viability of L929 mouse fibroblasts and U87 human glioblastoma epithelial cells. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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7 pages, 1871 KiB  
Article
Development of a Sensitive Induction-Based Magnetic Nanoparticle Biodetection Method
by Jakob Blomgren, Fredrik Ahrentorp, Dag Ilver, Christian Jonasson, Sobhan Sepehri, Alexei Kalaboukhov, Dag Winkler, Teresa Zardán Gómez de la Torre, Maria Strømme and Christer Johansson
Nanomaterials 2018, 8(11), 887; https://doi.org/10.3390/nano8110887 - 01 Nov 2018
Cited by 8 | Viewed by 3049
Abstract
We developed a novel biodetection method for influenza virus based on AC magnetic susceptibility measurement techniques (the DynoMag induction technique) together with functionalized multi-core magnetic nanoparticles. The sample consisting of an incubated mixture of magnetic nanoparticles and rolling circle amplified DNA coils is [...] Read more.
We developed a novel biodetection method for influenza virus based on AC magnetic susceptibility measurement techniques (the DynoMag induction technique) together with functionalized multi-core magnetic nanoparticles. The sample consisting of an incubated mixture of magnetic nanoparticles and rolling circle amplified DNA coils is injected into a tube by a peristaltic pump. The sample is moved as a plug to the two well-balanced detection coils and the dynamic magnetic moment in each position is read over a range of excitation frequencies. The time for making a complete frequency sweep over the relaxation peak is about 5 minutes (10 Hz–10 kHz with 20 data points). The obtained standard deviation of the magnetic signal at the relaxation frequency (around 100 Hz) is equal to about 10−5 (volume susceptibility SI units), which is in the same range obtained with the DynoMag system. The limit of detection with this method is found to be in the range of 1 pM. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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16 pages, 3414 KiB  
Article
Unravelling the Thermal Decomposition Parameters for The Synthesis of Anisotropic Iron Oxide Nanoparticles
by Geoffrey Cotin, Céline Kiefer, Francis Perton, Dris Ihiawakrim, Cristina Blanco-Andujar, Simona Moldovan, Christophe Lefevre, Ovidiu Ersen, Benoit Pichon, Damien Mertz and Sylvie Bégin-Colin
Nanomaterials 2018, 8(11), 881; https://doi.org/10.3390/nano8110881 - 29 Oct 2018
Cited by 58 | Viewed by 5955
Abstract
Iron oxide nanoparticles are widely used as a contrast agent in magnetic resonance imaging (MRI), and may be used as therapeutic agent for magnetic hyperthermia if they display in particular high magnetic anisotropy. Considering the effect of nanoparticles shape on anisotropy, a reproducible [...] Read more.
Iron oxide nanoparticles are widely used as a contrast agent in magnetic resonance imaging (MRI), and may be used as therapeutic agent for magnetic hyperthermia if they display in particular high magnetic anisotropy. Considering the effect of nanoparticles shape on anisotropy, a reproducible shape control of nanoparticles is a current synthesis challenge. By investigating reaction parameters, such as the iron precursor structure, its water content, but also the amount of the surfactant (sodium oleate) reported to control the shape, iron oxide nanoparticles with different shape and composition were obtained, in particular, iron oxide nanoplates. The effect of the surfactant coming from precursor was taking into account by using in house iron stearates bearing either two or three stearate chains and the negative effect of water on shape was confirmed by considering these precursors after their dehydration. Iron stearates with three chains in presence of a ratio sodium oleate/oleic acid 1:1 led mainly to nanocubes presenting a core-shell Fe1−xO@Fe3−xO4 composition. Nanocubes with straight faces were only obtained with dehydrated precursors. Meanwhile, iron stearates with two chains led preferentially to the formation of nanoplates with a ratio sodium oleate/oleic acid 4:1. The rarely reported flat shape of the plates was confirmed with 3D transmission electronic microscopy (TEM) tomography. The investigation of the synthesis mechanisms confirmed the major role of chelating ligand and of the heating rate to drive the cubic shape of nanoparticles and showed that the nanoplate formation would depend mainly on the nucleation step and possibly on the presence of a given ratio of oleic acid and chelating ligand (oleate and/or stearate). Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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11 pages, 2353 KiB  
Article
Magnetic Nanoparticles Create Hot Spots in Polymer Matrix for Controlled Drug Release
by Esther Cazares-Cortes, Maria Nerantzaki, Jérôme Fresnais, Claire Wilhelm, Nébéwia Griffete and Christine Ménager
Nanomaterials 2018, 8(10), 850; https://doi.org/10.3390/nano8100850 - 18 Oct 2018
Cited by 30 | Viewed by 5223
Abstract
Herein, original magnetic drug delivery nanomaterials for cancer therapy are developed and compared, with the purpose to show active control over drug release by using an alternative magnetic field (AMF). The rationale is to combine polymers and superparamagnetic nanoparticles to trigger such drug [...] Read more.
Herein, original magnetic drug delivery nanomaterials for cancer therapy are developed and compared, with the purpose to show active control over drug release by using an alternative magnetic field (AMF). The rationale is to combine polymers and superparamagnetic nanoparticles to trigger such drug release under AMF. Two magnetic nanosystems are thus presented: magnetic nanogels made of thermosensitive and biocompatible polymers and core-shell nanoparticles with a magnetic core and a molecularly imprinted polymer as shell. Both encapsulate doxorubicin (DOX) and the DOX controlled release was investigated in vitro and in cells under AMF excitation. It confirms that the local heat profile at the vicinity of the iron oxide core can be used for the DOX controlled release. It also shows that both nanosystems help delivering more DOX inside the cells compared to internalization of free DOX. Finally, the DOX intracellular release could be remotely triggered under AMF, in athermal conditions, thus enhancing DOX cytotoxicity. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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19 pages, 5285 KiB  
Article
PEGylation of Superparamagnetic Iron Oxide Nanoparticles with Self-Organizing Polyacrylate-PEG Brushes for Contrast Enhancement in MRI Diagnosis
by Erzsébet Illés, Márta Szekeres, Ildikó Y. Tóth, Katalin Farkas, Imre Földesi, Ákos Szabó, Béla Iván and Etelka Tombácz
Nanomaterials 2018, 8(10), 776; https://doi.org/10.3390/nano8100776 - 29 Sep 2018
Cited by 28 | Viewed by 3928
Abstract
For biomedical applications, superparamagnetic nanoparticles (MNPs) have to be coated with a stealth layer that provides colloidal stability in biological media, long enough persistence and circulation times for reaching the expected medical aims, and anchor sites for further attachment of bioactive agents. One [...] Read more.
For biomedical applications, superparamagnetic nanoparticles (MNPs) have to be coated with a stealth layer that provides colloidal stability in biological media, long enough persistence and circulation times for reaching the expected medical aims, and anchor sites for further attachment of bioactive agents. One of such stealth molecules designed and synthesized by us, poly(polyethylene glycol methacrylate-co-acrylic acid) referred to as P(PEGMA-AA), was demonstrated to make MNPs reasonably resistant to cell internalization, and be an excellent candidate for magnetic hyperthermia treatments in addition to possessing the necessary colloidal stability under physiological conditions (Illés et al. J. Magn. Magn. Mater. 2018, 451, 710–720). In the present work, we elaborated on the molecular background of the formation of the P(PEGMA-AA)-coated MNPs, and of their remarkable colloidal stability and salt tolerance by using potentiometric acid–base titration, adsorption isotherm determination, infrared spectroscopy (FT-IR ATR), dynamic light scattering, and electrokinetic potential determination methods. The P(PEGMA-AA)@MNPs have excellent blood compatibility as demonstrated in blood sedimentation, smears, and white blood cell viability experiments. In addition, blood serum proteins formed a protein corona, protecting the particles against aggregation (found in dynamic light scattering and electrokinetic potential measurements). Our novel particles also proved to be promising candidates for MRI diagnosis, exhibiting one of the highest values of r2 relaxivity (451 mM−1s−1) found in literature. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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12 pages, 21595 KiB  
Article
Coarse-Grained Molecular Dynamics Modelling of a Magnetic Polymersome
by Aleksandr Ryzhkov and Yuriy Raikher
Nanomaterials 2018, 8(10), 763; https://doi.org/10.3390/nano8100763 - 27 Sep 2018
Cited by 10 | Viewed by 3139
Abstract
A coarse-grained molecular dynamics framework is proposed to investigate the equilibrium structure and quasi-static deformational response of a magnetic polymersome, a hollow object whose magnetoactive part is its shell (membrane). In the developed scheme, the shell is modelled as a pair of two [...] Read more.
A coarse-grained molecular dynamics framework is proposed to investigate the equilibrium structure and quasi-static deformational response of a magnetic polymersome, a hollow object whose magnetoactive part is its shell (membrane). In the developed scheme, the shell is modelled as a pair of two concentric interfaces, between which a layer of a linearly viscous fluid filled with magnetic nanoparticles is confined; the thickness of this layer slightly exceeds the nanoparticle diameter. The shell boundaries possess weak bending elasticity, very high surface tension and are impermeable for the nanoparticles. The nanoparticles bear permanent magnetic moments and are translationally and rotationally free inside the layer. The factors favoring the particle aggregation are the magneto-dipole coupling and Zeeman interaction with the external field; the impeding factors are thermal motion and steric restrictions imposed by the boundaries. The volume content of magnetic phase in the shell is sufficiently small (below 11 vol.%) to enable one to clearly observe structure patterns occurring in the basic state and under an applied magnetic field. As shown, both the particle concentration and the level of interparticle interaction strongly affect the extent and type of the aggregation that, in turn, causes overall deformation of the polymersome: stretching along the applied field and shrinking in the transverse plane. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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15 pages, 3910 KiB  
Article
Magnetic Targeting of Growth Factors Using Iron Oxide Nanoparticles
by Michal Marcus, Alexandra Smith, Ahmad Maswadeh, Ziv Shemesh, Idan Zak, Menachem Motiei, Hadas Schori, Shlomo Margel, Amos Sharoni and Orit Shefi
Nanomaterials 2018, 8(9), 707; https://doi.org/10.3390/nano8090707 - 10 Sep 2018
Cited by 45 | Viewed by 5001
Abstract
Growth factors play an important role in nerve regeneration and repair. An attractive drug delivery strategy, termed “magnetic targeting”, aims to enhance therapeutic efficiency by directing magnetic drug carriers specifically to selected cell populations that are suitable for the nervous tissues. Here, we [...] Read more.
Growth factors play an important role in nerve regeneration and repair. An attractive drug delivery strategy, termed “magnetic targeting”, aims to enhance therapeutic efficiency by directing magnetic drug carriers specifically to selected cell populations that are suitable for the nervous tissues. Here, we covalently conjugated nerve growth factor to iron oxide nanoparticles (NGF-MNPs) and used controlled magnetic fields to deliver the NGF–MNP complexes to target sites. In order to actuate the magnetic fields a modular magnetic device was designed and fabricated. PC12 cells that were plated homogenously in culture were differentiated selectively only in targeted sites out of the entire dish, restricted to areas above the magnetic “hot spots”. To examine the ability to guide the NGF-MNPs towards specific targets in vivo, we examined two model systems. First, we injected and directed magnetic carriers within the sciatic nerve. Second, we injected the MNPs intravenously and showed a significant accumulation of MNPs in mouse retina while using an external magnet that was placed next to one of the eyes. We propose a novel approach to deliver drugs selectively to injured sites, thus, to promote an effective repair with minimal systemic side effects, overcoming current challenges in regenerative therapeutics. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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16 pages, 3676 KiB  
Article
Development of Magnetically Active Scaffolds for Bone Regeneration
by Esperanza Díaz, Mᵃ Blanca Valle, Sylvie Ribeiro, Senentxu Lanceros-Mendez and José Manuel Barandiarán
Nanomaterials 2018, 8(9), 678; https://doi.org/10.3390/nano8090678 - 30 Aug 2018
Cited by 20 | Viewed by 3316
Abstract
This work reports on the synthesis, with the thermally induced phase separation (TIPS) technique, of poly (l-lactide) (PLLA) scaffolds containing Fe-doped hydroxyapatite (FeHA) particles for bone regeneration. Magnetization curves and X-ray diffraction indicate two magnetic particle phases: FeHA and magnetite Fe [...] Read more.
This work reports on the synthesis, with the thermally induced phase separation (TIPS) technique, of poly (l-lactide) (PLLA) scaffolds containing Fe-doped hydroxyapatite (FeHA) particles for bone regeneration. Magnetization curves and X-ray diffraction indicate two magnetic particle phases: FeHA and magnetite Fe3O4. Magnetic nanoparticles (MNPs) are approximately 30 ± 5 nm in width and 125 ± 25 nm in length, and show typical ferromagnetic properties, including coercivity and rapid saturation magnetization. Scanning electron microscopy (SEM) images of the magnetic scaffolds reveal their complex morphology changes with MNP concentration. Similarly, at compositions of approximately 20% MNPs, the phase separation changes, passing from solid–liquid to liquid–liquid as revealed by the hill-like structures, with low peaks that give the walls in the SEM images a surface pattern of micro-ruggedness typical of nucleation mechanisms and growth. In vitro degradation experiments, carried out for more than 28 weeks, demonstrated that the MNPs delay the scaffold degradation process. Cytotoxicity is appreciated for FeHA content above 20%. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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29 pages, 4643 KiB  
Article
Kinetics of Aggregation and Magnetic Separation of Multicore Iron Oxide Nanoparticles: Effect of the Grafted Layer Thickness
by Hinda Ezzaier, Jéssica Alves Marins, Cyrille Claudet, Gauvin Hemery, Olivier Sandre and Pavel Kuzhir
Nanomaterials 2018, 8(8), 623; https://doi.org/10.3390/nano8080623 - 17 Aug 2018
Cited by 26 | Viewed by 5361
Abstract
In this work, we have studied field-induced aggregation and magnetic separation—realized in a microfluidic channel equipped with a single magnetizable micropillar—of multicore iron oxide nanoparticles (IONPs) also called “nanoflowers” of an average size of 27 ± 4 nm and covered by either a [...] Read more.
In this work, we have studied field-induced aggregation and magnetic separation—realized in a microfluidic channel equipped with a single magnetizable micropillar—of multicore iron oxide nanoparticles (IONPs) also called “nanoflowers” of an average size of 27 ± 4 nm and covered by either a citrate or polyethylene (PEG) monolayer having a thickness of 0.2–1 nm and 3.4–7.8 nm, respectively. The thickness of the adsorbed molecular layer is shown to strongly affect the magnetic dipolar coupling parameter because thicker molecular layers result in larger separation distances between nanoparticle metal oxide multicores thus decreasing dipolar magnetic forces between them. This simple geometrical constraint effect leads to the following important features related to the aggregation and magnetic separation processes: (a) Thinner citrate layer on the IONP surface promotes faster and stronger field-induced aggregation resulting in longer and thicker bulk needle-like aggregates as compared to those obtained with a thicker PEG layer; (b) A stronger aggregation of citrated IONPs leads to an enhanced retention capacity of these IONPs by a magnetized micropillar during magnetic separation. However, the capture efficiency Λ at the beginning of the magnetic separation seems to be almost independent of the adsorbed layer thickness. This is explained by the fact that only a small portion of nanoparticles composes bulk aggregates, while the main part of nanoparticles forms chains whose capture efficiency is independent of the adsorbed layer thickness but depends solely on the Mason number Ma. More precisely, the capture efficiency shows a power law trend Λ ∝ M a − n , with n ≈ 1.4–1.7 at 300 < Ma < 104, in agreement with a new theoretical model. Besides these fundamental issues, the current work shows that the multicore IONPs with a size of about 30 nm have a good potential for use in biomedical sensor applications where an efficient low-field magnetic separation is required. In these applications, the nanoparticle surface design should be carried out in a close feedback with the magnetic separation study in order to find a compromise between biological functionalities of the adsorbed molecular layer and magnetic separation efficiency. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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14 pages, 2688 KiB  
Article
Distribution of Paramagnetic Fe2O3/SiO2–Core/Shell Nanoparticles in the Rat Lung Studied by Time-of-Flight Secondary Ion Mass Spectrometry: No Indication for Rapid Lipid Adsorption
by Lothar Veith, Antje Vennemann, Daniel Breitenstein, Carsten Engelhard, Birgit Hagenhoff and Martin Wiemann
Nanomaterials 2018, 8(8), 571; https://doi.org/10.3390/nano8080571 - 26 Jul 2018
Cited by 6 | Viewed by 4594
Abstract
Amorphous silica nanoparticles comprise a class of widely used industrial nanomaterials, which may elicit acute inflammation in the lung. These materials have a large specific surface to which components of the pulmonary micro-milieu can bind. To conduct appropriate binding studies, paramagnetic Fe2 [...] Read more.
Amorphous silica nanoparticles comprise a class of widely used industrial nanomaterials, which may elicit acute inflammation in the lung. These materials have a large specific surface to which components of the pulmonary micro-milieu can bind. To conduct appropriate binding studies, paramagnetic Fe2O3/SiO2 core/shell nanoparticles (Fe-Si-NP) may be used as an easy-to-isolate silica surrogate, if several prerequisites are fulfilled. To this end, we investigated the distribution of Fe, Si, protein and phosphatidylcholine (PC) by Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) in cryo-sections from the rat lungs to which Fe-Si-NP had been administered for 30 min. Regions-of-interest were identified and analyzed with incident light and enhanced dark-field microscopy (DFM). Fe-Si-NP particles (primary particle size by electron microscopy: 10–20 nm; aggregate size by tracking analysis: 190 ± 20 nm) and agglomerates thereof were mainly attached to alveolar walls and only marginally internalized by cells such as alveolar macrophages. The localization of Fe-Si-NP by DFM was confirmed by ToF-SIMS signals from both, Fe and Si ions. With respect to an optimized signal-to-noise ratio, Fe+, Si+, CH4N+ and the PC head group (C5H15NO4P+) were the most versatile ions to detect iron, silica, protein, and PC, respectively. Largely congruent Fe+ and Si+ signals demonstrated that the silica coating of Fe-Si-NP remained stable under the conditions of the lung. PC, as a major lipid of the pulmonary surfactant, was colocalized with the protein signal alongside alveolar septa, but was not detected on Fe-Si-NP, suggesting that silica nanoparticles do not adsorb lipids of the lung surfactant under native conditions. The study shows that ToF-SIMS is a valuable technique with adequate spatial resolution to analyze nanoparticles together with organic molecules in the lung. The paramagnetic Fe-Si-NP appear well suited to study the binding of proteins to silica nanomaterials in the lung. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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16 pages, 2418 KiB  
Article
Combined Treatments of Magnetic Intra-Lysosomal Hyperthermia with Doxorubicin Promotes Synergistic Anti-Tumoral Activity
by Darine El Hajj Diab, Pascal Clerc, Nizar Serhan, Daniel Fourmy and Véronique Gigoux
Nanomaterials 2018, 8(7), 468; https://doi.org/10.3390/nano8070468 - 27 Jun 2018
Cited by 9 | Viewed by 3157
Abstract
Doxorubicin is a cytotoxic drug used for the treatment of many cancer types. However, its significant dose-related adverse effects including cardiotoxicity may hamper its efficiency. Moreover, the multidrug resistance that appears during treatments limits anti-cancer therapies. Hyperthermia has been introduced as an adjuvant [...] Read more.
Doxorubicin is a cytotoxic drug used for the treatment of many cancer types. However, its significant dose-related adverse effects including cardiotoxicity may hamper its efficiency. Moreover, the multidrug resistance that appears during treatments limits anti-cancer therapies. Hyperthermia has been introduced as an adjuvant anti-cancer therapy and presents promising opportunities especially in combination with chemotherapy. However, hyperthermia methods including standard magnetic hyperthermia do not discriminate between the target and the surrounding normal tissues and can lead to side effects. In this context, a Magnetic Intra-Lysosomal Hyperthermia (MILH) approach, which occurs without perceptible temperature rise, has been developed. We previously showed that minute amounts of iron oxide magnetic nanoparticles targeting the gastrin receptor (CCK2R) are internalized by cancer cells through a CCK2R-dependent physiological process, accumulated into their lysosomes and kill cancer cells upon high frequency alternating magnetic field (AMF) application through lysosomal cell death. Here, we show that the combination of MILH with doxorubicin increases the efficiency of the eradication of endocrine tumor cells with synergism. We also demonstrate that these two treatments activate two different cell death pathways that are respectively dependent on Caspase-1 and Caspase-3 activation. These findings will result in the development of new anti-tumoral, intra-lysosomal-thermo/chemotherapy with better curative effects than chemotherapy alone and that are devoid of adverse effects linked to standard hyperthermia approaches. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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15 pages, 6019 KiB  
Article
Role of Mn2+ Doping in the Preparation of Core-Shell Structured Fe3O4@upconversion Nanoparticles and Their Applications in T1/T2-Weighted Magnetic Resonance Imaging, Upconversion Luminescent Imaging and Near-Infrared Activated Photodynamic Therapy
by Yang Luo, Wei Zhang, Zhengfang Liao, Shengnan Yang, Shengtao Yang, Xinhua Li, Fang Zuo and Jianbin Luo
Nanomaterials 2018, 8(7), 466; https://doi.org/10.3390/nano8070466 - 26 Jun 2018
Cited by 14 | Viewed by 5050
Abstract
Core-shell (C/S) structured upconversion coated Fe3O4 nanoparticles (NPs) are of great interest due to their potential as magnetic resonance imaging (MRI) and upconversion luminescent (UCL) imaging agents, as well as near-infrared activated photodynamic therapy (PDT) platforms. When C/S structured Fe [...] Read more.
Core-shell (C/S) structured upconversion coated Fe3O4 nanoparticles (NPs) are of great interest due to their potential as magnetic resonance imaging (MRI) and upconversion luminescent (UCL) imaging agents, as well as near-infrared activated photodynamic therapy (PDT) platforms. When C/S structured Fe3O4@Mn2+-doped NaYF4:Yb/Er NPs were prepared previously, well-defined C/S-NPs could not be formed without the doping of Mn2+ during synthesis. Here, the role of Mn2+ doping on the synthesis of core-shell structured magnetic-upconversion nanoparticles (MUCNPs) is investigated in detail. Core-shell-shell nanoparticles (C/S/S-MUCNPs) with Fe3O4 as the core, an inert layer of Mn2+-doped NaYF4 and an outer shell consisting of Mn2+-doped NaYF4:Yb/Er were prepared. To further develop C/S/S-MUCNPs applications in the biological field, amphiphilic poly(maleic anhydride-alt-1-octadecene) (C18PMH) modified with amine functionalized methoxy poly(ethylene glycol) (C18PMH-mPEG) was used as a capping ligand to modify the surface of C/S/S-MUCNPs to improve biocompatibility. UCL imaging, T1-weighted MRI ascribed to the Mn2+ ions and T2-weighted MRI ascribed to the Fe3O4 core of C/S/S-MUCNPs were then evaluated. Finally, chlorine e6 (Ce6) was loaded on the C/S/S-MUCNPs and the PDT performance of these NPs was explored. Mn2+ doping is an effective method to control the formation of core-shell structured MUCNPs, which would be potential candidate as multifunctional nanoprobes for future T1/T2-weighted MR/UCL imaging and PDT platforms. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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22 pages, 7207 KiB  
Article
Iron Oxide Colloidal Nanoclusters as Theranostic Vehicles and Their Interactions at the Cellular Level
by Athanasia Kostopoulou, Konstantinos Brintakis, Eirini Fragogeorgi, Amalia Anthousi, Liberato Manna, Sylvie Begin-Colin, Claire Billotey, Anthi Ranella, George Loudos, Irene Athanassakis and Alexandros Lappas
Nanomaterials 2018, 8(5), 315; https://doi.org/10.3390/nano8050315 - 09 May 2018
Cited by 23 | Viewed by 5333
Abstract
Advances in surfactant-assisted chemical approaches have led the way for the exploitation of nanoscale inorganic particles in medical diagnosis and treatment. In this field, magnetically-driven multimodal nanotools that perform both detection and therapy, well-designed in size, shape and composition, are highly advantageous. Such [...] Read more.
Advances in surfactant-assisted chemical approaches have led the way for the exploitation of nanoscale inorganic particles in medical diagnosis and treatment. In this field, magnetically-driven multimodal nanotools that perform both detection and therapy, well-designed in size, shape and composition, are highly advantageous. Such a theranostic material—which entails the controlled assembly of smaller (maghemite) nanocrystals in a secondary motif that is highly dispersible in aqueous media—is discussed here. These surface functionalized, pomegranate-like ferrimagnetic nanoclusters (40–85 nm) are made of nanocrystal subunits that show a remarkable magnetic resonance imaging contrast efficiency, which is better than that of the superparamagnetic contrast agent Endorem©. Going beyond this attribute and with their demonstrated low cytotoxicity in hand, we examine the critical interaction of such nanoprobes with cells at different physiological environments. The time-dependent in vivo scintigraphic imaging of mice experimental models, combined with a biodistribution study, revealed the accumulation of nanoclusters in the spleen and liver. Moreover, the in vitro proliferation of spleen cells and cytokine production witnessed a size-selective regulation of immune system cells, inferring that smaller clusters induce mainly inflammatory activities, while larger ones induce anti-inflammatory actions. The preliminary findings corroborate that the modular chemistry of magnetic iron oxide nanoclusters stimulates unexplored pathways that could be driven to alter their function in favor of healthcare. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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17 pages, 3922 KiB  
Article
Bare Iron Oxide Nanoparticles for Magnetic Harvesting of Microalgae: From Interaction Behavior to Process Realization
by Paula Fraga-García, Peter Kubbutat, Markus Brammen, Sebastian Schwaminger and Sonja Berensmeier
Nanomaterials 2018, 8(5), 292; https://doi.org/10.3390/nano8050292 - 01 May 2018
Cited by 63 | Viewed by 7655
Abstract
Microalgae continue to gain in importance as a bioresource, while their harvesting remains a major challenge at the moment. This study presents findings on microalgae separation using low-cost, easy-to-process bare iron oxide nanoparticles with the additional contribution of the upscaling demonstration of this [...] Read more.
Microalgae continue to gain in importance as a bioresource, while their harvesting remains a major challenge at the moment. This study presents findings on microalgae separation using low-cost, easy-to-process bare iron oxide nanoparticles with the additional contribution of the upscaling demonstration of this simple, adhesion-based process. The high affinity of the cell wall for the inorganic surface enables harvesting efficiencies greater than 95% for Scenedesmus ovalternus and Chlorella vulgaris. Successful separation is possible in a broad range of environmental conditions and primarily depends on the nanoparticle-to-microalgae mass ratio, whereas the effect of pH and ionic strength are less significant when the mass ratio is chosen properly. The weakening of ionic concentration profiles at the interphase due to the successive addition of deionized water leads the microalgae to detach from the nanoparticles. The process works efficiently at the liter scale, enabling complete separation of the microalgae from their medium and the separate recovery of all materials (algae, salts, and nanoparticles). The current lack of profitable harvesting processes for microalgae demands innovative approaches to encourage further development. This application of magnetic nanoparticles is an example of the prospects that nanobiotechnology offers for biomass exploitation. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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9 pages, 3983 KiB  
Communication
Can Pulsed Electromagnetic Fields Trigger On-Demand Drug Release from High-Tm Magnetoliposomes?
by Martina Nardoni, Elena Della Valle, Micaela Liberti, Michela Relucenti, Maria Antonietta Casadei, Patrizia Paolicelli, Francesca Apollonio and Stefania Petralito
Nanomaterials 2018, 8(4), 196; https://doi.org/10.3390/nano8040196 - 27 Mar 2018
Cited by 22 | Viewed by 4619
Abstract
Recently, magnetic nanoparticles (MNPs) have been used to trigger drug release from magnetoliposomes through a magneto-nanomechanical approach, where the mechanical actuation of the MNPs is used to enhance the membrane permeability. This result can be effectively achieved with low intensity non-thermal alternating magnetic [...] Read more.
Recently, magnetic nanoparticles (MNPs) have been used to trigger drug release from magnetoliposomes through a magneto-nanomechanical approach, where the mechanical actuation of the MNPs is used to enhance the membrane permeability. This result can be effectively achieved with low intensity non-thermal alternating magnetic field (AMF), which, however, found rare clinic application. Therefore, a different modality of generating non-thermal magnetic fields has now been investigated. Specifically, the ability of the intermittent signals generated by non-thermal pulsed electromagnetic fields (PEMFS) were used to verify if, once applied to high-transition temperature magnetoliposomes (high-Tm MLs), they could be able to efficiently trigger the release of a hydrophilic model drug. To this end, hydrophilic MNPs were combined with hydrogenated soybean phosphatidylcholine and cholesterol to design high-Tm MLs. The release of a dye was evaluated under the effect of PEMFs for different times. The MNPs motions produced by PEMF could effectively increase the bilayer permeability, without affecting the liposomes integrity and resulted in nearly 20% of release after 3 h exposure. Therefore, the current contribution provides an exciting proof-of-concept for the ability of PEMFS to trigger drug release, considering that PEMFS find already application in therapy due to their anti-inflammatory effects. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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13 pages, 5653 KiB  
Article
Optimization of Iron Oxide Tracer Synthesis for Magnetic Particle Imaging
by Sabina Ziemian, Norbert Löwa, Olaf Kosch, Daniel Bajj, Frank Wiekhorst and Gunnar Schütz
Nanomaterials 2018, 8(4), 180; https://doi.org/10.3390/nano8040180 - 21 Mar 2018
Cited by 22 | Viewed by 4706
Abstract
The optimization of iron oxide nanoparticles as tracers for magnetic particle imaging (MPI) alongside the development of data acquisition equipment and image reconstruction techniques is crucial for the required improvements in image resolution and sensitivity of MPI scanners. We present a large-scale water-based [...] Read more.
The optimization of iron oxide nanoparticles as tracers for magnetic particle imaging (MPI) alongside the development of data acquisition equipment and image reconstruction techniques is crucial for the required improvements in image resolution and sensitivity of MPI scanners. We present a large-scale water-based synthesis of multicore superparamagnetic iron oxide nanoparticles stabilized with dextran (MC-SPIONs). We also demonstrate the preparation of single core superparamagnetic iron oxide nanoparticles in organic media, subsequently coated with a poly(ethylene glycol) gallic acid polymer and phase transferred to water (SC-SPIONs). Our aim was to obtain long-term stable particles in aqueous media with high MPI performance. We found that the amplitude of the third harmonic measured by magnetic particle spectroscopy (MPS) at 10 mT is 2.3- and 5.8-fold higher than Resovist for the MC-SPIONs and SC-SPIONs, respectively, revealing excellent MPI potential as compared to other reported MPI tracer particle preparations. We show that the reconstructed MPI images of phantoms using optimized multicore and specifically single-core particles are superior to that of commercially available Resovist, which we utilize as a reference standard, as predicted by MPS. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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13 pages, 1662 KiB  
Article
Magnetic Nanoparticles Interact and Pass an In Vitro Co-Culture Blood-Placenta Barrier Model
by Elena K. Müller, Christine Gräfe, Frank Wiekhorst, Christian Bergemann, Andreas Weidner, Silvio Dutz and Joachim H. Clement
Nanomaterials 2018, 8(2), 108; https://doi.org/10.3390/nano8020108 - 14 Feb 2018
Cited by 32 | Viewed by 5055
Abstract
Magnetic nanoparticles are interesting tools for biomedicine. Before application, critical prerequisites have to be fulfilled. An important issue is the contact and interaction with biological barriers such as the blood-placenta barrier. In order to study these processes in detail, suitable in vitro models [...] Read more.
Magnetic nanoparticles are interesting tools for biomedicine. Before application, critical prerequisites have to be fulfilled. An important issue is the contact and interaction with biological barriers such as the blood-placenta barrier. In order to study these processes in detail, suitable in vitro models are needed. For that purpose a blood-placenta barrier model based on the trophoblast-like cell line BeWo and primary placenta-derived pericytes was established. This model was characterized by molecular permeability, transepithelial electrical resistance and cell-cell-contact markers. Superparamagnetic iron oxide nanoparticles (SPIONs) with cationic, anionic or neutral surface charge were applied. The localization of the nanoparticles within the cells was illustrated by histochemistry. The time-dependent passage of the nanoparticles through the BeWo/pericyte barrier was measured by magnetic particle spectroscopy and atomic absorption spectroscopy. Cationically coated SPIONs exhibited the most extensive interaction with the BeWo cells and remained primarily in the BeWo/pericyte cell layer. In contrast, SPIONs with neutral and anionic surface charge were able to pass the cell layer to a higher extent and could be detected beyond the barrier after 24 h. This study showed that the mode of SPION interaction with and passage through the in vitro blood-placenta barrier model depends on the surface charge and the duration of treatment. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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14 pages, 2845 KiB  
Communication
Improved Anticancer Effect of Magnetite Nanocomposite Formulation of GALLIC Acid (Fe3O4-PEG-GA) Against Lung, Breast and Colon Cancer Cells
by Raihana Rosman, Bullo Saifullah, Sandra Maniam, Dena Dorniani, Mohd Zobir Hussein and Sharida Fakurazi
Nanomaterials 2018, 8(2), 83; https://doi.org/10.3390/nano8020083 - 02 Feb 2018
Cited by 54 | Viewed by 5633
Abstract
Lung cancer, breast cancer and colorectal cancer are the most prevalent fatal types of cancers globally. Gallic acid (3,4,5-trihydroxybenzoic acid) is a bioactive compound found in plants and foods, such as white tea, witch hazel and it has been reported to possess anticancer, [...] Read more.
Lung cancer, breast cancer and colorectal cancer are the most prevalent fatal types of cancers globally. Gallic acid (3,4,5-trihydroxybenzoic acid) is a bioactive compound found in plants and foods, such as white tea, witch hazel and it has been reported to possess anticancer, antioxidant and anti-inflammatory properties. In this study we have redesigned our previously reported anticancer nanocomposite formulation with improved drug loading based on iron oxide magnetite nanoparticles coated with polyethylene glycol and loaded with anticancer drug gallic acid (Fe3O4-PEG-GA). The in vitro release profile and percentage drug loading were found to be better than our previously reported formulation. The anticancer activity of pure gallic acid (GA), empty carrier (Fe3O4-PEG) nanocarrier and of anticancer nanocomposite (Fe3O4-PEG-GA) were screened against human lung cancer cells (A549), human breast cancer cells (MCF-7), human colon cancer cells (HT-29) and normal fibroblast cells (3T3) after incubation of 24, 48 and 72 h using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT assay. The designed formulation (Fe3O4-PEG-GA) showed better anticancer activity than free gallic acid (GA). The results of the in vitro studies are highly encouraging to conduct the in vivo studies. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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2372 KiB  
Article
A Novel Magnetic Actuation Scheme to Disaggregate Nanoparticles and Enhance Passage across the Blood–Brain Barrier
by Ali Kafash Hoshiar, Tuan-Anh Le, Faiz Ul Amin, Myeong Ok Kim and Jungwon Yoon
Nanomaterials 2018, 8(1), 3; https://doi.org/10.3390/nano8010003 - 22 Dec 2017
Cited by 29 | Viewed by 4918
Abstract
The blood–brain barrier (BBB) hinders drug delivery to the brain. Despite various efforts to develop preprogramed actuation schemes for magnetic drug delivery, the unmodeled aggregation phenomenon limits drug delivery performance. This paper proposes a novel scheme with an aggregation model for a feed-forward [...] Read more.
The blood–brain barrier (BBB) hinders drug delivery to the brain. Despite various efforts to develop preprogramed actuation schemes for magnetic drug delivery, the unmodeled aggregation phenomenon limits drug delivery performance. This paper proposes a novel scheme with an aggregation model for a feed-forward magnetic actuation design. A simulation platform for aggregated particle delivery is developed and an actuation scheme is proposed to deliver aggregated magnetic nanoparticles (MNPs) using a discontinuous asymmetrical magnetic actuation. The experimental results with a Y-shaped channel indicated the success of the proposed scheme in steering and disaggregation. The delivery performance of the developed scheme was examined using a realistic, three-dimensional (3D) vessel simulation. Furthermore, the proposed scheme enhanced the transport and uptake of MNPs across the BBB in mice. The scheme presented here facilitates the passage of particles across the BBB to the brain using an electromagnetic actuation scheme. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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2919 KiB  
Article
Influence of Sterilization and Preservation Procedures on the Integrity of Serum Protein-Coated Magnetic Nanoparticles
by Silvio Dutz, Stephanie Wojahn, Christine Gräfe, Andreas Weidner and Joachim H. Clement
Nanomaterials 2017, 7(12), 453; https://doi.org/10.3390/nano7120453 - 15 Dec 2017
Cited by 19 | Viewed by 4761
Abstract
Protein-coated magnetic nanoparticles are promising candidates for various medical applications. Prior to their application into a biological system, one has to guarantee that the particle dispersions are free from pathogens or any other microbiologic contamination. Furthermore, to find entrance into clinical routine, the [...] Read more.
Protein-coated magnetic nanoparticles are promising candidates for various medical applications. Prior to their application into a biological system, one has to guarantee that the particle dispersions are free from pathogens or any other microbiologic contamination. Furthermore, to find entrance into clinical routine, the nanoparticle dispersions have to be storable for several months. In this study, we tested several procedures for sterilization and preservation of nanoparticle containing liquids on their influence on the integrity of the protein coating on the surface of these particles. For this, samples were treated by freezing, autoclaving, lyophilization, and ultraviolet (UV) irradiation, and characterized by means of dynamic light scattering, determination of surface potential, and gel electrophoresis afterwards. We found that the UV sterilization followed by lyophilization under the addition of polyethylene glycol are the most promising procedures for the preparation of sterilized long-term durable protein-coated magnetic nanoparticles. Ongoing work is focused on the optimization of used protocols for UV sterilization and lyophilization for further improvement of the storage time. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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867 KiB  
Article
Surface Functionalization of Iron Oxide Nanoparticles with Gallic Acid as Potential Antioxidant and Antimicrobial Agents
by Syed Tawab Shah, Wageeh A Yehya, Omer Saad, Khanom Simarani, Zaira Chowdhury, Abeer A. Alhadi and Lina A. Al-Ani
Nanomaterials 2017, 7(10), 306; https://doi.org/10.3390/nano7100306 - 05 Oct 2017
Cited by 101 | Viewed by 8263
Abstract
In this research, we report the size-controlled synthesis and surface-functionalization of magnetite with the natural antioxidant gallic acid (GA) as a ligand, using in situ and post-synthesis methods. GA functionalization provided narrow size distribution, with an average particle size of 5 and 8 [...] Read more.
In this research, we report the size-controlled synthesis and surface-functionalization of magnetite with the natural antioxidant gallic acid (GA) as a ligand, using in situ and post-synthesis methods. GA functionalization provided narrow size distribution, with an average particle size of 5 and 8 nm for in situ synthesis of gallic acid functionalized magnetite IONP@GA1 and IONP@GA2, respectively, which are ultra-small particles as compared to unfunctionalized magnetite (IONP) and post functionalized magnetite IONP@GA3 with average size of 10 and 11 nm respectively. All the IONPs@GA samples were found hydrophilic with stable aggregation state. Prior to commencement of experimental lab work, PASS software was used to predict the biological activities of GA and it is found that experimental antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and antimicrobial studies using well diffusion method are in good agreement with the simulated results. Furthermore, the half maximal inhibitory concentration (IC50) values of DPPH antioxidant assay revealed a 2–4 fold decrease as compared to unfunctionalized IONP. In addition to antioxidant activity, all the three IONP@GA proved outstanding antimicrobial activity while testing on different bacterial and fungal strains. The results collectively indicate the successful fabrication of novel antioxidant, antimicrobial IONP@GA composite, which are magnetically separable, efficient, and low cost, with potential applications in polymers, cosmetics, and biomedical and food industries. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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3140 KiB  
Article
Tuning Properties of Iron Oxide Nanoparticles in Aqueous Synthesis without Ligands to Improve MRI Relaxivity and SAR
by Debora Bonvin, Duncan T. L. Alexander, Angel Millán, Rafael Piñol, Beatriz Sanz, Gerardo F. Goya, Abelardo Martínez, Jessica A. M. Bastiaansen, Matthias Stuber, Kurt J. Schenk, Heinrich Hofmann and Marijana Mionić Ebersold
Nanomaterials 2017, 7(8), 225; https://doi.org/10.3390/nano7080225 - 18 Aug 2017
Cited by 29 | Viewed by 4564
Abstract
Aqueous synthesis without ligands of iron oxide nanoparticles (IONPs) with exceptional properties still remains an open issue, because of the challenge to control simultaneously numerous properties of the IONPs in these rigorous settings. To solve this, it is necessary to correlate the synthesis [...] Read more.
Aqueous synthesis without ligands of iron oxide nanoparticles (IONPs) with exceptional properties still remains an open issue, because of the challenge to control simultaneously numerous properties of the IONPs in these rigorous settings. To solve this, it is necessary to correlate the synthesis process with their properties, but this correlation is until now not well understood. Here, we study and correlate the structure, crystallinity, morphology, as well as magnetic, relaxometric and heating properties of IONPs obtained for different durations of the hydrothermal treatment that correspond to the different growth stages of IONPs upon initial co-precipitation in aqueous environment without ligands. We find that their properties were different for IONPs with comparable diameters. Specifically, by controlling the growth of IONPs from primary to secondary particles firstly by colloidal and then also by magnetic interactions, we control their crystallinity from monocrystalline to polycrystalline IONPs, respectively. Surface energy minimization in the aqueous environment along with low temperature treatment is used to favor nearly defect-free IONPs featuring superior properties, such as high saturation magnetization, magnetic volume, surface crystallinity, the transversal magnetic resonance imaging (MRI) relaxivity (up to r2 = 1189 mM−1·s−1 and r2/r1 = 195) and specific absorption rate, SAR (up to 1225.1 W·gFe−1). Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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Review

Jump to: Research

19 pages, 4234 KiB  
Review
Magnetic Nanoparticles Applications for Amyloidosis Study and Detection: A Review
by Jonathan Pansieri, Matthieu Gerstenmayer, François Lux, Sebastien Mériaux, Olivier Tillement, Vincent Forge, Benoit Larrat and Christel Marquette
Nanomaterials 2018, 8(9), 740; https://doi.org/10.3390/nano8090740 - 18 Sep 2018
Cited by 41 | Viewed by 6092
Abstract
Magnetic nanoparticles (MNPs) have great potential in biomedical and clinical applications because of their many unique properties. This contribution provides an overview of the MNPs mainly used in the field of amyloid diseases. The first part discusses their use in understanding the amyloid [...] Read more.
Magnetic nanoparticles (MNPs) have great potential in biomedical and clinical applications because of their many unique properties. This contribution provides an overview of the MNPs mainly used in the field of amyloid diseases. The first part discusses their use in understanding the amyloid mechanisms of fibrillation, with emphasis on their ability to control aggregation of amyloidogenic proteins. The second part deals with the functionalization by various moieties of numerous MNPs’ surfaces (molecules, peptides, antibody fragments, or whole antibodies of MNPs) for the detection and the quantification of amyloid aggregates. The last part of this review focuses on the use of MNPs for magnetic-resonance-based amyloid imaging in biomedical fields, with particular attention to the application of gadolinium-based paramagnetic nanoparticles (AGuIX), which have been recently developed. Biocompatible AGuIX nanoparticles show favorable characteristics for in vivo use, such as nanometric and straightforward functionalization. Their properties have enabled their application in MRI. Here, we report that AGuIX nanoparticles grafted with the Pittsburgh compound B can actively target amyloid aggregates in the brain, beyond the blood–brain barrier, and remain the first step in observing amyloid plaques in a mouse model of Alzheimer’s disease. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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22 pages, 342 KiB  
Review
Magnetic Hyperthermia and Radiation Therapy: Radiobiological Principles and Current Practice †
by Spiridon V. Spirou, Martina Basini, Alessandro Lascialfari, Claudio Sangregorio and Claudia Innocenti
Nanomaterials 2018, 8(6), 401; https://doi.org/10.3390/nano8060401 - 03 Jun 2018
Cited by 115 | Viewed by 7263
Abstract
Hyperthermia, though by itself generally non-curative for cancer, can significantly increase the efficacy of radiation therapy, as demonstrated by in vitro, in vivo, and clinical results. Its limited use in the clinic is mainly due to various practical implementation difficulties, the most important [...] Read more.
Hyperthermia, though by itself generally non-curative for cancer, can significantly increase the efficacy of radiation therapy, as demonstrated by in vitro, in vivo, and clinical results. Its limited use in the clinic is mainly due to various practical implementation difficulties, the most important being how to adequately heat the tumor, especially deep-seated ones. In this work, we first review the effects of hyperthermia on tissue, the limitations of radiation therapy and the radiobiological rationale for combining the two treatment modalities. Subsequently, we review the theory and evidence for magnetic hyperthermia that is based on magnetic nanoparticles, its advantages compared with other methods of hyperthermia, and how it can be used to overcome the problems associated with traditional techniques of hyperthermia. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
31 pages, 1752 KiB  
Review
Recommendations for In Vitro and In Vivo Testing of Magnetic Nanoparticle Hyperthermia Combined with Radiation Therapy
by Spiridon V. Spirou, Sofia A. Costa Lima, Penelope Bouziotis, Sanja Vranješ-Djurić, Eleni Κ. Efthimiadou, Anna Laurenzana, Ana Isabel Barbosa, Ignacio Garcia-Alonso, Carlton Jones, Drina Jankovic and Oliviero L. Gobbo
Nanomaterials 2018, 8(5), 306; https://doi.org/10.3390/nano8050306 - 06 May 2018
Cited by 50 | Viewed by 7697
Abstract
Magnetic nanoparticle (MNP)-mediated hyperthermia (MH) coupled with radiation therapy (RT) is a novel approach that has the potential to overcome various practical difficulties encountered in cancer treatment. In this work, we present recommendations for the in vitro and in vivo testing and application [...] Read more.
Magnetic nanoparticle (MNP)-mediated hyperthermia (MH) coupled with radiation therapy (RT) is a novel approach that has the potential to overcome various practical difficulties encountered in cancer treatment. In this work, we present recommendations for the in vitro and in vivo testing and application of the two treatment techniques. These recommendations were developed by the members of Working Group 3 of COST Action TD 1402: Multifunctional Nanoparticles for Magnetic Hyperthermia and Indirect Radiation Therapy (“Radiomag”). The purpose of the recommendations is not to provide definitive answers and directions but, rather, to outline those tests and considerations that a researcher must address in order to perform in vitro and in vivo studies. The recommendations are divided into 5 parts: (a) in vitro evaluation of MNPs; (b) in vitro evaluation of MNP-cell interactions; (c) in vivo evaluation of the MNPs; (d) MH combined with RT; and (e) pharmacokinetic studies of MNPs. Synthesis and characterization of the MNPs, as well as RT protocols, are beyond the scope of this work. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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29 pages, 8983 KiB  
Review
Iron Oxide and Gold Based Magneto-Plasmonic Nanostructures for Medical Applications: A Review
by Thi Thuy Nguyen, Fayna Mammeri and Souad Ammar
Nanomaterials 2018, 8(3), 149; https://doi.org/10.3390/nano8030149 - 07 Mar 2018
Cited by 72 | Viewed by 11527
Abstract
Iron oxide and gold-based magneto-plasmonic nanostructures exhibit remarkable optical and superparamagnetic properties originating from their two different components. As a consequence, they have improved and broadened the application potential of nanomaterials in medicine. They can be used as multifunctional nanoprobes for magneto-plasmonic heating [...] Read more.
Iron oxide and gold-based magneto-plasmonic nanostructures exhibit remarkable optical and superparamagnetic properties originating from their two different components. As a consequence, they have improved and broadened the application potential of nanomaterials in medicine. They can be used as multifunctional nanoprobes for magneto-plasmonic heating as well as for magnetic and optical imaging. They can also be used for magnetically assisted optical biosensing, to detect extreme traces of targeted bioanalytes. This review introduces the previous work on magneto-plasmonic hetero-nanostructures including: (i) their synthesis from simple “one-step” to complex “multi-step” routes, including seed-mediated and non-seed-mediated methods; and (ii) the characterization of their multifunctional features, with a special emphasis on the relationships between their synthesis conditions, their structures and their properties. It also focuses on the most important progress made with regard to their use in nanomedicine, keeping in mind the same aim, the correlation between their morphology—namely spherical and non-spherical, core-satellite and core-shell, and the desired applications. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles in Biological Applications)
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