Simulated Clustering Dynamics of Colloidal Magnetic Nanoparticles

AbstractMethods to form magnetic nanoparticle monolayers using non-aqueous Langmuir layers are reported. Following a discussion of the driving forces in various self-assembly techniques, we describe how aqueous Langmuir layers can be modified for use in conjunction with oxidationsensitive nanoparticles. Monolayers are formed using Fe and–Co nanoparticles, and transferred to carbon-coated transmission electron microscopy grids using the Langmuir-Schaefer method.

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A Perspective on Modelling Metallic Magnetic Nanoparticles in Biomedicine: From Monometals to Nanoalloys and Ligand-Protected Particles

Materials ◽

10.3390/ma14133611 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3611

Author(s):

Barbara Farkaš ◽

Nora H. de de Leeuw

Keyword(s):

Magnetic Nanoparticles ◽

Biomedical Applications ◽

Magnetic Nanoparticle ◽

Cobalt Nanoparticles ◽

Magnetic Behaviour ◽

Resonance Imaging ◽

Magnetic Nanoparticle Hyperthermia ◽

Magnetic Resonance Imaging Mri ◽

Simulation Systems

The focus of this review is on the physical and magnetic properties that are related to the efficiency of monometallic magnetic nanoparticles used in biomedical applications, such as magnetic resonance imaging (MRI) or magnetic nanoparticle hyperthermia, and how to model these by theoretical methods, where the discussion is based on the example of cobalt nanoparticles. Different simulation systems (cluster, extended slab, and nanoparticle models) are critically appraised for their efficacy in the determination of reactivity, magnetic behaviour, and ligand-induced modifications of relevant properties. Simulations of the effects of nanoscale alloying with other metallic phases are also briefly reviewed.

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Magnetic Nanoparticle-Mediated Heating for Biomedical Applications

Journal of Heat Transfer ◽

10.1115/1.4053007 ◽

2021 ◽

Author(s):

Elyahb Kwizera ◽

Samantha Stewart ◽

Md Musavvir Mahmud ◽

Xiaoming He

Keyword(s):

Magnetic Nanoparticles ◽

Biomedical Applications ◽

Magnetic Nanoparticle ◽

Focused Ultrasound ◽

High Intensity Focused Ultrasound ◽

Superparamagnetic Nanoparticles ◽

Heating Effect ◽

Facile Synthesis ◽

Magnetic Heating ◽

Different Types

Abstract Magnetic nanoparticles, especially superparamagnetic nanoparticles (SPIONs), have attracted tremendous attention for various biomedical applications. Facile synthesis and functionalization together with easy control of the size and shape of SPIONS to customize their unique properties, have made it possible to develop different types of SPIONs tailored for diverse functions/applications. More recently, considerable attention has been paid to the thermal effect of SPIONs for the treatment of diseases like cancer and for nanowarming of cryopreserved/banked cells, tissues, and organs. In this mini-review, recent advances on the magnetic heating effect of SPIONs for magnetothermal therapy and enhancement of cryopreservation of cells, tissues, and organs, are discussed, together with the non-magnetic heating effect (i.e., high Intensity focused ultrasound or HIFU-activated heating) of SPIONs for cancer therapy. Furthermore, challenges facing the use of magnetic nanoparticles in these biomedical applications are presented.

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Investigation of Magnetic Nanoparticle Motion under a Gradient Magnetic Field by an Electromagnet

Journal of Nanomaterials ◽

10.1155/2018/6246917 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Weizhong Wei ◽

Zhen Wang

Keyword(s):

Magnetic Field ◽

Finite Element ◽

Electromagnetic Field ◽

Magnetic Nanoparticles ◽

Particle Motion ◽

Biomedical Applications ◽

Magnetic Nanoparticle ◽

Magnetic Particles ◽

Magnetic Force ◽

Gradient Magnetic Field

Finite element numerical simulations were carried out in 2D geometry to calculate the magnetic force on magnetic nanoparticles under a specially fabricated electromagnet. The particle motion was modeled by a system of ordinary differential equations. The snapshots of trajectories of 4000 MNPs with and without magnetic field were analyzed and qualitatively found to be in agreement with camera visualizations of MNP movement in a container. The results of the analysis could be helpful for the design of electromagnetic field and motion analysis of magnetic particles for the delivery of magnetic materials in biomedical applications.

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Behaviors of Bio-Functionalized Magnetic Nanoparticle Clusters in a Rotating Magnetic Field

Volume 5: 6th International Conference on Micro- and Nanosystems; 17th Design for Manufacturing and the Life Cycle Conference ◽

10.1115/detc2012-70356 ◽

2012 ◽

Author(s):

Chin-Yih Hong ◽

Ji-Ching Lai ◽

Chia-Chung Tang

Keyword(s):

Magnetic Field ◽

Aqueous Solution ◽

Magnetic Nanoparticles ◽

Magnetic Fields ◽

Magnetic Nanoparticle ◽

Critical Diameter ◽

Rotating Magnetic Field ◽

Magnetic Clusters ◽

Rotating Magnetic Fields ◽

Nanoparticle Clusters

Manipulation of magnetic nanoparticles has many applications in several fields and the behaviors of magnetic nanoparticles subjected to rotating or alternating magnetic fields attracted more attention from biomedical applications. In an aqueous solution containing bio-functionalized magnetic nanoparticles, due to the interaction between biomolecules, these nanoparticles agglomerate and form clusters with various sizes and shapes. In this study, the behaviors of magnetic nanoparticle clusters in an aqueous solution under rotating magnetic fields were investigated. Due to the interaction between the rotating magnetic field and the net magnetic dipole moment, the clusters were subjected to forced vibration. Two motion modes of clusters were observed as the magnetic field rotated. These two modes are rotation and oscillation. The diameters of the magnetic clusters with rotational or oscillational motions were measured. A critical diameter range of magnetic cluster was defined and the range is between 10.21 μm and 6.17 μm that could be used to distinguish rotation and oscillation of clusters.

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Size selectable nanoparticle assemblies with magnetic anisotropy tunable across the superparamagnetic to ferromagnetic range

Chemical Communications ◽

10.1039/c6cc05871j ◽

2016 ◽

Vol 52 (91) ◽

pp. 13337-13340 ◽

Cited By ~ 5

Author(s):

Jacek K. Stolarczyk ◽

Carla J. Meledandri ◽

Sarah P. Clarke ◽

Dermot F. Brougham

Keyword(s):

Magnetic Anisotropy ◽

Biomedical Applications ◽

Magnetic Nanoparticle ◽

Nanoparticle Assemblies ◽

Novel Approach ◽

Nanoparticle Clusters

We present a novel approach for the preparation of magnetic nanoparticle clusters of controlled size and selectable magnetic anisotropy, which provides materials with properties selectable for biomedical applications and as components in magnetically responsive nanocomposites.

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A Bottom-Up Approach to Solution-Processed, Atomically Precise Graphitic Cylinders on Surfaces

10.26434/chemrxiv.7158959 ◽

2018 ◽

Author(s):

Erik Leonhardt ◽

Jeff M. Van Raden ◽

David Miller ◽

Lev N. Zakharov ◽

Benjamin Aleman ◽

...

Keyword(s):

Self Assembly ◽

Carbon Nanostructures ◽

Carbon Nanomaterials ◽

Circle Packing ◽

Pyrolytic Graphite ◽

Building Blocks ◽

Bottom Up ◽

Casting Technique ◽

New Class ◽

Solution Casting Technique

Extended carbon nanostructures, such as carbon nanotubes (CNTs), exhibit remarkable properties but are difficult to synthesize uniformly. Herein, we present a new class of carbon nanomaterials constructed via the bottom-up self-assembly of cylindrical, atomically-precise small molecules. Guided by supramolecular design principles and circle packing theory, we have designed and synthesized a fluorinated nanohoop that, in the solid-state, self-assembles into nanotube-like arrays with channel diameters of precisely 1.63 nm. A mild solution-casting technique is then used to construct vertical “forests” of these arrays on a highly-ordered pyrolytic graphite (HOPG) surface through epitaxial growth. Furthermore, we show that a basic property of nanohoops, fluorescence, is readily transferred to the bulk phase, implying that the properties of these materials can be directly altered via precise functionalization of their nanohoop building blocks. The strategy presented is expected to have broader applications in the development of new graphitic nanomaterials with π-rich cavities reminiscent of CNTs.

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Bottom-up Evolution from Disks to High-Genus Polymersomes

10.26434/chemrxiv.6108467.v1 ◽

2018 ◽

Author(s):

Claudia Contini ◽

Russell Pearson ◽

Linge Wang ◽

Lea Messager ◽

Jens Gaitzsch ◽

...

Keyword(s):

Self Assembly ◽

The Self ◽

Amphiphilic Copolymers ◽

Chain Entanglement ◽

Bottom Up ◽

New Approach ◽

High Genus ◽

Transmission Electron ◽

Minimal Radius ◽

Stop Flow

<div><div><div><p>We report the design of polymersomes using a bottom-up approach where the self-assembly of amphiphilic copolymers poly(2-(methacryloyloxy) ethyl phosphorylcholine)–poly(2-(diisopropylamino) ethyl methacrylate) (PMPC-PDPA) into membranes is tuned using pH and temperature. We study this process in detail using transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) spectroscopy, dynamic light scattering (DLS), and stop-flow ab- sorbance disclosing the molecular and supramolecular anatomy of each structure observed. We report a clear evolution from disk micelles to vesicle to high-genus vesicles where each passage is controlled by pH switch or temperature. We show that the process can be rationalised adapting membrane physics theories disclosing important scaling principles that allow the estimation of the vesiculation minimal radius as well as chain entanglement and coupling. This allows us to propose a new approach to generate nanoscale vesicles with genus from 0 to 70 which have been very elusive and difficult to control so far.</p></div></div></div>

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Bottom-up Evolution from Disks to High-Genus Polymersomes

10.26434/chemrxiv.6108467 ◽

2018 ◽

Author(s):

Claudia Contini ◽

Russell Pearson ◽

Linge Wang ◽

Lea Messager ◽

Jens Gaitzsch ◽

...

Keyword(s):

Self Assembly ◽

The Self ◽

Amphiphilic Copolymers ◽

Chain Entanglement ◽

Bottom Up ◽

New Approach ◽

High Genus ◽

Transmission Electron ◽

Minimal Radius ◽

Stop Flow

<div><div><div><p>We report the design of polymersomes using a bottom-up approach where the self-assembly of amphiphilic copolymers poly(2-(methacryloyloxy) ethyl phosphorylcholine)–poly(2-(diisopropylamino) ethyl methacrylate) (PMPC-PDPA) into membranes is tuned using pH and temperature. We study this process in detail using transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) spectroscopy, dynamic light scattering (DLS), and stop-flow ab- sorbance disclosing the molecular and supramolecular anatomy of each structure observed. We report a clear evolution from disk micelles to vesicle to high-genus vesicles where each passage is controlled by pH switch or temperature. We show that the process can be rationalised adapting membrane physics theories disclosing important scaling principles that allow the estimation of the vesiculation minimal radius as well as chain entanglement and coupling. This allows us to propose a new approach to generate nanoscale vesicles with genus from 0 to 70 which have been very elusive and difficult to control so far.</p></div></div></div>

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