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Bovine Serum Albumin-Conjugated ferrimagnetic Iron Oxide Nanoparticles to Enhance the Biocompatibility and Magnetic Hyperthermia Performance

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Nano-Micro Letters 2016年第1期8卷 80-93页

作者： Viveka Kalidasan Xiao Li Liu Tun Seng Herng Yong Yang Jun Ding Department of Materials Science and Engineering Faculty of Engineering National University of Singapore Shaanxi Key Laboratory of Degradable Biomedical Materials School of Chemical Engineering Northwest University

Magnetic hyperthermia is a fast emerging, non-invasive cancer treatment method which is used synergistically with the existing cancer therapeutics. We have attempted to address the current challenges in clinical magnetic hyperthermia-improved biocompatibility and enhanced heating characteristics, through a single combinatorial approach. Both superparamagnetic iron oxide nanoparticles(SPIONs) of size 10 nm and ferrimagnetic iron oxide nanoparticles(FIONs) of size 30 nm were synthesized by thermal decomposition method for comparison studies. Two different surface modifying agents, viz, Cetyl Trimethyl Ammonium Bromide and 3-Aminopropyltrimethoxysilane, were used to conjugate Bovine Serum Albumin(BSA) over the iron oxide nanoparticles via two different methods—surface charge adsorption and covalent amide bonding, respectively. The preliminary haemolysis and cell viability experiments show that BSA conjugation mitigates the haemolytic effect of the iron oxide nanoparticles on erythrocytes and is non-cytotoxic to the healthy Baby Hamster Kidney cells. It was observed from the results that due to better colloidal stability, the SAR value of the BSA-iron oxide nanoparticles is higher than the iron oxide nanoparticles without BSA, irrespective of the size of the iron oxide nanoparticles and method of conjugation. The BSA-FIONs seem to show improved biocompatibility, as the haemolytic index is less than 2 % and cell viability is up to 120 %, when normalized with the control. The SAR value of BSAFIONs is 2300 Wg^(-1) when compared to 1700 Wg^(-1) of FIONs without BSA conjugation. Thus, we report here that BSA conjugation over FIONs(with a high saturation magnetization of 87 emug^(-1)) provide a single combinatorial approach to improve the biocompatibility and enhance the SAR value for magnetic hyperthermia, thus addressing both the current challenges of the same.

关键词： Magnetic hyperthermia ferrimagnetic iron oxide nanoparticles Bovine serum albumin Haemolysis Cell viability Specific absorption rate

Mean-Field Solution of the Mixed Spin-2 and Spin-5/2 Ising ferrimagnetic System with Different Single-Ion Anisotropies

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Open Journal of Applied Sciences 2013年第3期3卷 270-277页

作者： Fathi Abubrig Department of Physics Faculty of Science Elmergeb University Zliten Libya

The mixed spin-2 and spin-5/2 Ising ferrimagnetic system with different anisotropies (DA/z|J|) for the spin-2 and (DB/z|J|) for the spin-5/2 is studied by the use of the mean-field theory based on the Bogoliubov inequality for the free energy. First, the ground state phase diagram of the system at zero temperature is obtained on the (DA/z|J|,DB/z|J|) plane. Topologically, different kinds of phase diagrams are achieved by changing the temperature and the values of the single ion anisotropies DA/z|J| and DB/z|J|. Besides second-order transition lines, first order phase transition lines terminating at tricritical points, are found. The existence and dependence of a compensation temperature on single-ion anisotropies is also investigated.

关键词： Mixed Spin Ising Model ferrimagnetic Sublattice Magnetization Tricritical Points

THE THERMAL EFFECT OF ferrimagnetic RESONANCE AND ITS PROBABLE APPLICATION IN MICROWAVE HYPERTHERMIA IN CANCER THERAPY

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Chinese Journal of Biomedical Engineering(English Edition) 1993年第1期2卷 26-32页

作者： Chen Guozhang, Wu Ganghua,Dong Dingwei Zhejiang Medical University Zhejiang Institute of Techonology

To improve microwave hyperthevmia in cancer therapy, the thermal effect of fer-rimagnetic resonance (FMR) during microwave irradiation was studied. Resonant temperatureelevation (RTE) of single crystal grain and polycrystal powder of resonant media was measuredalone and in imitative muscle and egg white and in mice. The results indicated that the RTE produced by FMR could be used to improve penetrationdeepness, heating selectivity and temperature distribution of microwave hyperthermia in cancertreatment. It was expected that the potential function of the FMR heating system would be ex-ploited greatly for cancer therapy, and then magnetically guided microwave hyperthermia thera-py, chemotherapy, radiotherapy and immunotherapy might he combined multiply within this sys-tem by means of the static magnetic field (SMF) and magnetic microcarrier. Limitation of reso-nant heating was also discussed in this paper.

关键词： magnetical guidance ferrimagnetic resonance microwave hyperthermia cancer therapy.

Charge transport and shot noise on the surface of a topological insulator with a magnetic modulation

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Chinese Physics B 2012年第4期21卷 461-466页

作者：袁建辉成泽张建军曾奇军张俊佩 School of Physics Huazhong University of Science and TechnologyWuhan 430074China

In this paper, we investigate the transport features and the Fano factor of Dirac electrons on the surface of a three-dimensional topological insulator with a magnetic modulation. We consider a hard wall bounding condition on the edge of the topological insulator, which implies that a surface state of the topological insulator is insulating. We find that a valley of conductivity at the Dirac point is associated with a Fano factor peak, and more interestingly, this topological metal changes from insulating to metallic by controlling the effective exchange field.

关键词： topological insulator electronic transport ferrimagnetic

Possible ferrimagnetism and ferroelectricity of half-substituted rare-earth titanate： A first-principles study on Y0.5La0.5TiO3

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Frontiers of physics 2016年第2期11卷 83-88页

作者： Ming An Hui-Min Zhang Ya-Kui Weng Yang Zhang Shuai Dong Department of Physics Southeast University Nanjing 211189 China

Titanates with the perovskite structure, including ferroelectrics （e.g., BaTiO3） and ferromagnetic ones （e.g., YTiO3）, are important functional materials. Recent theoretical studies predicted multi- ferroic states in strained EuTiO3 and titanate superlattices, the former of which has already been experimental confirmed. Here, a first-principles calculation is performed to investigate the struc- tural, magnetic, and electronic properties of Y half-substituted LaTiO3. Our results reveal that the magnetism of ***.5TiO3 sensitively depends on its structural details because of the inher- ent phase competition. The lowest energy state is the ferromagnetic state, resulting in 0.25 μB/Ti. Furthermore, some configurations of Y0.500La0.5TiO3 exhibit hybrid improper polarizations, which can be significantly affected by magnetism, resulting in the multiferroic properties. Because of the quenching disorder of substitution, the real Y0.5La0.5TiO3 material with random A-site ions may exhibit interesting relaxor behaviors.

关键词： titanate ferrimagnetic ferroelectricity

Magnetic mineral diagenesis in the post-glacial muddy sediments from the southeastern South Yellow Sea:Response to marine environmental changes

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Science China Earth Sciences 2005年第1期48卷 134-144页

作者： Jeong-Hae Chang Korean Institute of Geology

Core YSDP103 was retrieved in the muddy deposit under the cold eddy of the southeastern South Yellow Sea, and the uppermost 29.79 m core represents the muddy sediments formed in the shelf since about 13 ka BP. The lower part from 29.79 to 13.35 m, called Unit A2, was deposited during the period from the post-glacial transgression to the middle Holocene (at about 6 14C ka BP) when the rising sea level reached its maximum, while the upper part above 13.35 m (called Unit A1) was deposited in a cold eddy associated with the formation of the Yellow Sea Warm Current just after the peak of post-glacial sea level rise. Rock-magnetic properties of the uppermost 29.79 m core were investigated in detail. The experimental results indicate that the magnetic mineralogy of the core is dominated by magnetite, maghemite and hematite and that, except for the uppermost 2.35 m, the magnetic minerals were subject to reductive diagenesis leading to significant decline of magnetic mineral content and the proportion of low-coercivity component. More importantly, ferrimagnetic iron sulphide (greigite) is found in Unit A2 but absent in Unit A1, suggesting the control of marine environmental conditions on the magnetic mineral diagenesis. Magnetic parameters show abrupt changes across the boundary between Units A1and A2, which reflects a co-effect of environmental conditions and primary magnetic components of the sediments on the diagenesis. Alternating zones of high and low magnetic parameters are observed in Unit A2, which is presumably due to periodic changes of the concentration and/or grain size of magnetic minerals carried into the study area.

关键词： environmental magnetism, magnetic minerals, diagenesis, ferrimagnetic iron sulphide, South Yellow Sea.

Environmental mechanism of magnetic susceptibility changes of lacustrine sediments from Lake Hulun, China

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Science China Earth Sciences 2000年第5期43卷 534-540页

作者：胡守云王苏民 Erwin Appel 吉磊 Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Institut fur Geologie und Palaontologie Universitat Tubingen Tubingen 72076 Germany

The changes of magnetic susceptibility(κ) are correlated with those of corresponding sedimentological, geochemical, mineralogical and biological results, which verifies thatκ can be taken as one of the environmental proxies. However, usually the exact origin of magnetic signal is poorly understood, and is difficult to relate with the environmental evolution. Magnetic properties of material derived from the catchment and sedimentary environment may affect the accumulation, preservation, or authigenesis and diagenesis of magnetic minerals. In the Lake Hulun region in Inner Mongolia, it is found that muddy sediments, deposited during high water level period (corresponding to humid climate), have comparatively highκ values. In contrast, the sandy sediments, deposited during low water level period (corresponding to arid climate), have lowκ values. Detailed rock magnetic investigation confirms that detrital magnetite derived from volcanic rocks in the catchment exists in both muddy and sandy sediments. During high water level period, secondary ferrimagnetic iron sulphide was produced in muddy sediments under relatively reductive conditions. ferrimagnetic iron sulphide, coexisting with detrital magnetite, predominates the magnetic properties of muddy sediments, resulting in increasingκ. This paper reveals the significance of authigenic ferrimagnetic iron sulphide produced after sediment deposition.

关键词： lacustrine sediment magnetic susceptibility environmental magnetism ferrimagnetic iron sulphide Lake Hulun.

Study of the Crystallographic and Magnetic Structure in the Nickel Substituted Cobalt Ferrites by Neutron Diffraction

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Materials Sciences and Applications 2015年第4期6卷 332-342页

作者： Sadia Khanam A. K. M. Zakaria M. H. Ahsan T. K. Datta S. Aktar S. I. Liba S. Hossain A. K. Das I. Kamal S. M. Yunus D. K. Saha S.-G. Eriksson Department of Physics Shahjalal University of Science & Technology Sylhet Bangladesh Institute of Nuclear Science & Technology Bangladesh Atomic Energy Commission Dhaka Bangladesh Atomic Energy Centre Bangladesh Atomic Energy Commission Dhaka Bangladesh Department of Chemical and Biological Engineering Chalmers University of Technology Gothenburg Sweden

The polycrystalline spinel oxides NiX?Co1-X?Fe2O4 with composition x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 were prepared by conventional solid state ceramic sintering technique in air at 1300°C. X-ray diffraction experiments were carried out on all the samples at room temperature in order to characterize the materials. X-ray diffraction patterns showed sharp peaks indicating the formation of single phase cubic spinel structure. The neutron diffraction experiments were performed on all samples at room temperature, with an incident monochromatic neutron beam of wavelength λ = 1.5656 Å. The experimental neutron diffraction data were analyzed using the computer program FullProf in the Reitveld method. Reitveld refinement of the neutron diffraction data reveals that the samples possess cubic symmetry corresponding to the space group F d-3m. Cation distribution between the two sublattices of the spinel structure has been found from the analysis of the neutron diffraction data. Lattice parameters, oxygen position parameters, and overall temperature factors have also been determined from the analysis of neutron diffraction data. The lattice parameter decreases and oxygen position parameter increases with increasing Ni content in the system. Sublattices and net magnetic moments have been determined from the refinement of neutron diffraction data. The magnetic structure at room temperature was found to be ferrimagnetic for all the samples.

关键词： Ferrites Spinel Structure Crystal Structure Neutron Diffraction ferrimagnetic

Effect of Zn Substitution on the Magnetic and Magnetocapacitance Properties of Nanosized Multiferroic GaFeO<sub>3</sub>Ceramics

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New Journal of Glass and Ceramics 2018年第4期8卷 55-63页

作者： Tai-Chun Han Chun Yen Yi-De Chung Meng-Lin Wu Department of Applied Physics National University of Kaohsiung Taiwan

This article aims to investigate the possibility to turn the multiferroic orders and magnetocapacitance effect close to/above room temperature in nanosized GaFeO3 ceramics by a sol-gel preparation method and substitution with non-magnetic Zn atoms. Therefore, in this work, we have synthesized a series of nanocrystalline Ga1-xZnxFeO3(GZFO, x = 0, 0.01, 0.05 and 0.1) ceramic samples and study the effect of Zn substitution on their structural, magnetic, and electric properties. All the GZFO samples have an orthorhombic structure with Pc21n space group and the value of lattice parameters increase systematically with increasing Zn concentration. Interestingly, it shows that magnetic and electric properties are strongly dependent on the Zn substitution concentration. Based on the results of temperature-dependent magnetizations, M(T), it is observed that with increasing Zn-content up to 0.10, the ferrimagnetic transition temperature (TC) increases from 306 to 320 K. It is also found that the nanocrystalline Zn-doped GaFeO3 (GFO) samples exhibit the characteristics of ferroelectricity at room temperature. Furthermore, the?magnetization, ferroelectric polarization and magnetocapacitance of Zn-doped GFO nanosized ceramics are enhanced compared to those of the pristine sample of GFO ferrite. These results open wide perspectives for the applications of room temperature multiferroic devices.

关键词： Ferrite Multiferroic ferrimagnetic Ferroelectric Ceramics Zn Substitution