Mechanism for Sustainable Magnetic Nanoparticles under Ambient Conditions

N. H. Hai,N. D. Phu,N. H. Luong,N. Chau,H. D. Chinh,L. H. Hoang,D. L. Leslie-Pelecky 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.5

Iron-based magnetic fluids are widely used in physical applications. Recently, they have been extended to many biological applications due to their magnetic and biocompatible properties. However, their stability under an ambient environment still has not been systematically investigated. In this report, we present the oxidation process of magnetic fluids. The oxidation process depends on the materials that make the nanoparticles, the diffusion of oxygen atoms from the environment to the magnetic nanoparticles, which mainly depends on the viscosity of the solution and the surfactant that coats the nanoparticles. We suggest three ways to protect nanoparticles from oxidation: (a) using highly viscous carrier liquid (b) using relevant surfactants and (c) substitution of Ni²+ and Co²+ for Fe²+ in magnetite. Methods (a) and (b) are general, so they can be applied for many environmentally sensitive magnetic fluids. Method (c) is specific for a magnetite fluid. Iron-based magnetic fluids are widely used in physical applications. Recently, they have been extended to many biological applications due to their magnetic and biocompatible properties. However, their stability under an ambient environment still has not been systematically investigated. In this report, we present the oxidation process of magnetic fluids. The oxidation process depends on the materials that make the nanoparticles, the diffusion of oxygen atoms from the environment to the magnetic nanoparticles, which mainly depends on the viscosity of the solution and the surfactant that coats the nanoparticles. We suggest three ways to protect nanoparticles from oxidation: (a) using highly viscous carrier liquid (b) using relevant surfactants and (c) substitution of Ni²+ and Co²+ for Fe²+ in magnetite. Methods (a) and (b) are general, so they can be applied for many environmentally sensitive magnetic fluids. Method (c) is specific for a magnetite fluid.

Construction of magnetic nanochains to achieve magnetic energy coupling in scaffold

Cijun Shuai,Xuan Chen,Chongxian He,Guowen Qian,Yang Shuai,SHUPING PENG,Youwen Deng,Wenjing Yang 한국생체재료학회 2022 생체재료학회지 Vol.26 No.3

Background: Fe3O4 nanoparticles are highly desired for constructing endogenous magnetic microenvironment in scaffold to accelerate bone regeneration due to their superior magnetism. However, their random arrangement easily leads to mutual consumption of magnetic poles, thereby weakening the magnetic stimulation effect. Methods: In this study, magnetic nanochains are synthesized by magnetic-field-guided interface co-assembly of Fe3O4 nanoparticles. In detail, multiple Fe3O4 nanoparticles are aligned along the direction of magnetic force lines and are connected in series to form nanochain structures under an external magnetic field. Subsequently, the nanochain structures are covered and fixed by depositing a thin layer of silica (SiO2), and consequently forming linear magnetic nanochains (Fe3O4@SiO2). The Fe3O4@SiO2 nanochains are then incorporated into poly l-lactic acid (PLLA) scaffold prepared by selective laser sintering technology. Results: The results show that the Fe3O4@SiO2 nanochains with unique core–shell structure are successfully constructed. Meanwhile, the orderly assembly of nanoparticles in the Fe3O4@SiO2 nanochains enable to form magnetic energy coupling and obtain a highly magnetic micro-field. The in vitro tests indicate that the PLLA/Fe3O4@SiO2 scaffolds exhibit superior capacity in enhancing cell activity, improving osteogenesis-related gene expressions, and inducing cell mineralization compared with PLLA and PLLA/Fe3O4 scaffolds. Conclusion: In short, the Fe3O4@SiO2 nanochains endow scaffolds with good magnetism and cytocompatibility, which have great potential in accelerating bone repair

His-tagged protein immobilization on cationic ferrite magnetic nanoparticles

박성진,김승연,김승훈,박경민,황병희 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.6

Magnetic nanoparticles have been applied in various fields because of their interesting magnetic properties. Immobilization on magnetic nanoparticles is a very important step in functionalizing them. We examined protein immobilization efficiency using interactions between his-tagged enhanced green fluorescence protein and affordable cationic ferrite magnetic nanoparticles for the first time. Four types of ferrite magnetic nanoparticles were verified: cobalt iron oxide, copper iron oxide, nickel iron oxide, and iron (III) oxide as negative controls. Among the four ferrite magnetic nanoparticles, copper ferrite magnetic nanoparticle was confirmed to have the highest immobilization efficiency at 3.0mg proteins per gram ferrite magnetic nanoparticle and 78% of total enhanced green fluorescence protein. In addition, the maximum binding efficiency was determined for copper ferrite magnetic nanoparticle. Consequently, this newly verified his-tag-immobilizing capacity of copper ferrite magnetic nanoparticle could provide a facile, capable, and promising strategy for immobilizing his-tagged proteins or peptides with high purity for biosensors, magnetic separation, or diagnostics.

자성나노입자의 의학적 응용

이일수 한국물리학회 2015 새물리 Vol.65 No.5

Magnetic nanoparticles have attracted much attention for medical applications as carriers in nano drug delivery systems, contrast agents in magnetic resonance imaging (MRI), and heat generators in magnetic hyperthermia. Liposome and polymeric nanoparticles have been widely used clinically as carriers in nano drug delivery systems. On the other hand, magnetic nanoparticles have an advantage in that they can be used to trace the nano drug delivery system to the targeted tissue by using an MRI scanner. Thus, research on the surface modification of magnetic nanoparticles and the labeling of the targeting ligand and drug inside or on the surface of nanoparticles is being performed. Various types of magnetic nanoparticle contrast agents are currently used clinically in MRI scanning. Magnetic nanoparticles are also used to increase the tissue’s uptake of the drug carried by the nano drug delivery system and to kill malignant tissues by magnetic hyperthermia. These are possible because magnetic nanoparticles can generate heat via an external AC field. In this paper, we will investigate the present status and the future of medical applications of magnetic nanoparticles. 자성나노입자는 의학적으로 자기적 약물전달, MRI 조영제, 자기적 발열요법 등에 응용되고 있다. 나노약물전달시스템 (nano drug delivery system)의 캐리어 (carrier)로는 리포좀 (liposome)과 폴리머 나노입자가 가장 많이 연구되었고, 또한 임상으로도 많이 이용되고 있다. 그러나 자성나노입자를 나노약물전달에서 캐리어로 이용할 경우 그 자기적 성질을 이용할 수 있으므로 약물전달시스템의 추적 등에서 유리하다. 이에 따라 자성나노입자를 이용한 나노약물전달에 대한 관심이 높아지고 있다. 즉, 자성나노입자의 표면을 개질하여 표적 리간드와 약물을 부착하는 연구가 진행 중이다. 그리고 자성나노입자는 MRI에서 핵스핀의 이완을 가속시켜 영상대비를 좋게 만드는 조영제로 널리 이용되고 있다. 또한, 자성나노입자는 외부 AC 자기장에 의해 열을 발생하므로 나노약물전달에서 약물의 흡수율을 증가시키는데 사용하거나, 종양 세포의 온도를 42 ℃ 이상 올려서 종양 세포를 제거하는 발열요법에 사용할 수 있다. 이에 대한 연구와 동물실험이 계속되고 있다. 이 논문에서는 위와 같은 자성나노입자의 의학적 응용에 있어서 그 원리, 현재 상황, 및 미래의 추세에 대해 알아보았다.

Magnetic nanoparticles for bioseparation

Hira Fatima,김교선 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.3

Magnetic bioseparation has been an essential process for decades in all areas of biosciences. A variety of separation processes are being developed. Recently, much attention is being paid to applying magnetic nanoparticles for magnetic bioseparation. The purpose of this review paper is to show the importance of magnetic bioseparation by magnetic nanoparticles. Several synthesis and modification methods of magnetic nanoparticles are documented along with interactions involved in binding of the biomolecules with magnetic nanoparticles. Some practical examples of magnetic bioseparation processes are also discussed to show the efficiency of magnetic bioseparation technique.

Synthesis and Physicochemical Characterization of Biodegradable PLGA-based Magnetic Nanoparticles Containing Amoxicilin

Somayeh Alimohammadi,Roya Salehi, Niloofar Amini,Soodabeh Davaran,Niloofar Amini 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.10

The purposes of this research were to synthesize amoxicillin-carrying magnetic nanoparticles. Magnetic nanoparticles were prepared by a chemical precipitation of ferric and ferrous chloride salts in the presence of a strong basic solution. PLGA and PLGA-PEG copolymers were prepared by ring opening polymerization of lactide (LA) and glycolide (GA) (mole ratio of LA: GA 3:1) with or without polyethylene glycol (PEG). Amoxicillin loaded magnetic PLGA and PLGA-PEG nanoparticles were prepared by an emulsion-evaporation process (o/w). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) photomicrographs showed that the magnetic nanoparticles have the mean diameter within the range of 65-260 nm also they were almost spherical in shape. Magnetic nanoparticles prepared with PLGA showed more efficient entrapment (90%) as compared with PLGA-PEG (48-52%) nanoparticles. In-vitro release of amoxicillin from magnetic PLGA nanoparticles showed that 78% of drug was released over 24 hours. The amount of amoxicillin released from PLGA-PEG s was higher than PLGA.

Synthesis and Physicochemical Characterization of Biodegradable PLGA-based Magnetic Nanoparticles Containing Amoxicilin

Alimohammadi, Somayeh,Salehi, Roya,Amini, Niloofar,Davaran, Soodabeh Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.10

The purposes of this research were to synthesize amoxicillin-carrying magnetic nanoparticles. Magnetic nanoparticles were prepared by a chemical precipitation of ferric and ferrous chloride salts in the presence of a strong basic solution. PLGA and PLGA-PEG copolymers were prepared by ring opening polymerization of lactide (LA) and glycolide (GA) (mole ratio of LA: GA 3:1) with or without polyethylene glycol (PEG). Amoxicillin loaded magnetic PLGA and PLGA-PEG nanoparticles were prepared by an emulsion-evaporation process (o/w). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) photomicrographs showed that the magnetic nanoparticles have the mean diameter within the range of 65-260 nm also they were almost spherical in shape. Magnetic nanoparticles prepared with PLGA showed more efficient entrapment (90%) as compared with PLGA-PEG (48-52%) nanoparticles. In-vitro release of amoxicillin from magnetic PLGA nanoparticles showed that 78% of drug was released over 24 hours. The amount of amoxicillin released from PLGA-PEG s was higher than PLGA.

Studies of aggregated nanoparticles steering during magnetic-guided drug delivery in the blood vessels

Hoshiar, Ali Kafash,Le, Tuan-Anh,Amin, Faiz Ul,Kim, Myeong Ok,Yoon, Jungwon Elsevier 2017 Journal of magnetism and magnetic materials Vol.427 No.-

<P><B>Abstract</B></P> <P>Magnetic-guided targeted drug delivery (TDD) systems can enhance the treatment of diverse diseases. Despite the potential and promising results of nanoparticles, aggregation prevents precise particle guidance in the vasculature. In this study, we developed a simulation platform to investigate aggregation during steering of nanoparticles using a magnetic field function. The magnetic field function (MFF) comprises a positive and negative pulsed magnetic field generated by electromagnetic coils, which prevents adherence of particles to the vessel wall during magnetic guidance. A commonly used Y-shaped vessel was simulated and the performance of the MFF analyzed; the experimental data were in agreement with the simulation results. Moreover, the effects of various parameters on magnetic guidance were evaluated and the most influential identified. The simulation results presented herein will facilitate more precise guidance of nanoparticles in vivo.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We developed a simulation platform to investigate aggregation of nanoparticles. </LI> <LI> The influential parameters for magnetic steering of a Y-shaped vessel were identified. </LI> <LI> The proposed platform will facilitate more precise guidance of nanoparticles in vivo. </LI> </UL> </P>

Brain tumor targeting of magnetic nanoparticles for potential drug delivery: Effect of administration route and magnetic field topography

Chertok, Beata,David, Allan E.,Yang, Victor C. Elsevier 2011 Journal of controlled release Vol.155 No.3

<P><B>Abstract</B></P><P>Our previous studies demonstrated feasibility of magnetically-mediated retention of iron oxide nanoparticles in brain tumors after intravascular administration. The purpose of this study was to elucidate strategies for further improvement of this promising approach. In particular, we explored administration of the nanoparticles via a non-occluded carotid artery as a way to increase the passive exposure of tumor vasculature to nanoparticles for subsequent magnetic entrapment. However, aggregation of nanoparticles in the afferent vasculature interfered with tumor targeting. The magnetic setup employed in our experiments was found to generate a relatively uniform magnetic flux density over a broad range, exposing the region of the afferent vasculature to high magnetic force. To overcome this problem, the magnetic setup was modified with a 9-mm diameter cylindrical NdFeB magnet to exhibit steeper magnetic field topography. Six-fold reduction of the magnetic force at the injection site, achieved with this modification, alleviated the aggregation problem under the conditions of intact carotid blood flow. Using this setup, carotid administration was found to present 1.8-fold increase in nanoparticle accumulation in glioma compared to the intravenous route at 350mT. This increase was found to be in reasonable agreement with the theoretically estimated 1.9-fold advantage of carotid administration, <I>R</I><SUB><I>d</I></SUB>. The developed approach is expected to present an even greater advantage when applied to drug-loaded nanoparticles exhibiting higher values of <I>R</I><SUB><I>d</I></SUB>.</P> <P><B>Graphical abstract</B></P><P><ce:figure id='f0035'></ce:figure></P>

Effect of Shape Magnetic Anisotropy of Amorphous Fe-B-P Nanoparticles on Permeability

Ji Eun Lee,Bulgan Tsedenbal,Bon Heun Koo,Seok Hwan Huh 한국재료학회 2020 한국재료학회지 Vol.30 No.11

Many electronic applications require magnetic materials with high permeability and frequency properties. We improve the magnetic permeability of soft magnetic powder by controlling the shape magnetic anisotropy of the powders and through the preparation of amorphous nanoparticles. For this purpose, the effect of the shape magnetic anisotropy of amorphous Fe-B-P nanoparticles is observed through a magnetic field and the frequency characteristics and permeability of these amorphous nanoparticles are observed. These characteristics are investigated by analyzing the composition of particles, crystal structure, microstructure, magnetic properties, and permeability of particles. The composition, crystal structure, and microstructure of the particles are analyzed using inductively coupled plasma optical emission spectrometry, X-ray diffraction, scanning electron microscopy and focused ion beam analysis. The saturation magnetization and permeability are measured using a vibrating sample magnetometer and an LCR meter, respectively. It is confirmed that the shape magnetic anisotropy of the particles influences the permeability. Finally, the permeability and frequency characteristics of the amorphous Fe-B-P nanoparticles are improved.