%0 Conference Paper
%A Qdemat, Asmaa
%T Magnetic Nanoparticles: From Nanoscale to Mesoscale
%M FZJ-2021-01627
%D 2021
%X Magnetic nanoparticles find promising applications in biomedicine. Examples of these applications include new methods for cancer treatment, such as magnetic drug targeting [1] and magnetic hyperthermia [2], or it can be used as contrast agents or tracers in magnetic resonance imaging [3] and magnetic particle imaging [4]. Such applications require magnetic nanoparticles with customized structural and magnetic properties, strongly dependent on particle size and shape [5]. Nanoparticle's shape is of key importance and significantly impacts their magnetic properties for their use in several applications. The nanoparticles' magnetic shape anisotropy can be assumed much larger than the magnetocrystalline anisotropy and can strongly affect magnetic moments orientation inside the particles. Moreover, the dipolar interaction between the nanoparticles depends on the particle shape and will influence the structural agglomerate formation.Recent advances in nanoparticle synthesis techniques have enabled the synthesis of a wide variety of precisely controlled, non-spherical particles, including cubes, cube-like shapes [6], and ellipsoids. Nanoparticles with a shape that deviates from a perfect cube have gained much interest and become experimentally available because they strongly influence the nanocubes' large-scale arrangement. Cube Nanoparticles with rounded edges result in an anisotropic shape known as a superellipsoid [7] or superball, which is an asymmetric body that describes the shape that smoothly interpolates between a sphere and a cube. To the best of my knowledge, there's no available theoretical model for the evaluation of SAXS data of particles with superball shape, and only it has been approximated by spheres of different radii [8]. Therefore, a theoretical form factor for a more precise evaluation of the SAXS data of superball particles has been developed, and it will be presented in our contribution.Also, in this contribution, we will present a combined study of magnetic field-dependent SAXS and XPCS measurements on hematite (α-Fe2O3) nanospindles, giving insight into the particle morphological information (length, radius, size distribution), magnetic orientation, and microscopic dynamics (relaxation of nanospindles). Hematite nanospindles are receiving considerable attention due to their unique behavior in an applied magnetic field. In contrast to other elongated nanoparticles, they bear a strong magnetocrystalline anisotropy and orient with their long axis perpendicular to an applied magnetic field above the Morin transition (TM = 263 K) [9].Moreover, we will show in our contribution the field-dependent polarized SANS results of different nanospheres. Additionally, SANSPOL results with and without applied magnetic field on pure dispersion of hematite nanospindles and for hybrid ferrofluidic dispersion consisting of hematite nanospindles decorated with spherical ferrite nanoparticles will be presented. The in-situ structure formation in such hybrid ferrofluids includes the orientational behavior of anisotropic structures as a function of the applied magnetic field to elucidate the correlation of superstructure formation and ferrofluidic properties, is studied.References[1] Mejías, R., Pérez-Yagüe, S., Gutiérrez, L. et al. (2011). Dimercaptosuccinic acid-coated magnetite nanoparticles for magnetically guided in vivo delivery of interferon gamma for cancer immunotherapy. Biomaterials, 32(11), 2938–2952. https://doi.org/10.1016/j.biomaterials.2011.01.008[2] Maier-Hauff, K., Ulrich, F., Nestler, D. et al. (2011). Efficacy and safety of intratumoral thermotherapy using magnetic iron-oxide nanoparticles combined with external beam radiotherapy on patients with recurrent glioblastoma multiforme. Journal of Neuro-Oncology, 103(2), 317–324. https://doi.org/10.1007/s11060-010-0389-0[3] Shin, T.-H., Choi, Y., Kim, S., & Cheon, J. (2015). Recent advances in magnetic nanoparticle-based multi-modal imaging. Chemical Society Reviews, 44(14), 4501–4516. https://doi.org/10.1039/C4CS00345D[4] Khandhar, A. P., Ferguson, R. M., Arami, H., & Krishnan, K. M. (2013). Monodisperse magnetite nanoparticle tracers for in vivo magnetic particle imaging. Biomaterials, 34(15), 3837–3845. https://doi.org/10.1016/j.biomaterials.2013.01.087[5] Hilger, I., & Kaiser, W. A. (2012). Iron oxide-based nanostructures for MRI and magnetic hyperthermia. Nanomedicine, 7(9), 1443–1459. https://doi.org/10.2217/nnm.12.112[6] Wetterskog, E., Agthe, M., Mayence, A.et al. (2014). Precise control over shape and size of iron oxide nanocrystals suitable for assembly into ordered particle arrays. Science and Technology of Advanced Materials, 15(5), 055010. https://doi.org/10.1088/1468-6996/15/5/055010[7] Rossi, L., Sacanna, S., Irvine, W. T. M., Chaikin, P. M., Pine, D. J., & Philipse, A. P. (2011). Cubic crystals from cubic colloids. Soft Matter, 7(9), 4139–4142. https://doi.org/10.1039/C0SM01246G[8] Donaldson, J. G., Linse, P., & Kantorovich, S. S. (2017). How cube-like must magnetic nanoparticles be to modify their self-assembly? Nanoscale, 9(19), 6448–6462. https://doi.org/10.1039/C7NR01245D[9] Morrish A H. (1994). Canted Antiferromagnetism: Hematite, (Singapore: World Scientific)
%B Digital Institute Seminar JCNS-2
%C 8 Apr 2021 - 8 Apr 2021, online event (online event)
Y2 8 Apr 2021 - 8 Apr 2021
M2 online event, online event
%F PUB:(DE-HGF)31
%9 Talk (non-conference)
%U https://juser.fz-juelich.de/record/891616