caa a22 4500 605545332 CHVBK 20210128100935.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s00723-015-0667-2 doi (NATIONALLICENCE)springer-10.1007/s00723-015-0667-2 Effect of Functional Group and Surface Charge of PEG and Dextran-Coated USPIO as a Contrast Agent in MRI on Relaxivity Constant [Elektronische Daten] [Nastaran Najafian, Saeed Shanehsazzadeh, Farzaneh Hajesmaeelzadeh, Afsaneh Lahooti, Cordula Gruettner, Mohammad Oghabian] The challenges in molecular imaging are focused on the development of novel contrast agents with much lower relaxation times. Ultrasmall superparamagnetic iron oxide nanoparticles known as USPIO have been used for a variety of applications such as imaging of cancer, apoptosis, and hyperthermia providing higher signal changes based on $$T_{2}^{*}$$ T 2 ∗ weighted susceptibility effects. Although many studies had been performed on USPIO there is still a lack of data on the effects of the physicochemical properties of these nanoparticles (NP) such as hydrodynamic size, surface charge and type of functional groups, which may alter the relaxivity of these NPs. The aim of this study was to evaluate the effect of different functional groups and surface charges of PEGylated and dextran-coated NPs on their magnetic properties. All relaxometry studies were performed using a 3-T magnetic resonance imaging. Our results showed that the impact of charge on magnetic properties is much higher than that of coating thickness. In this respect, particles with positive surface charges showed higher r 2/r 1 ratios. Springer-Verlag Wien, 2015 Najafian Nastaran Biomolecular Imaging Analysis Group (BIAG), Research Center for Molecular and Cellular Imaging (RCMCI), Tehran University of Medical Sciences, Tehran, Iran aut Shanehsazzadeh Saeed Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran aut Hajesmaeelzadeh Farzaneh Biomolecular Imaging Analysis Group (BIAG), Research Center for Molecular and Cellular Imaging (RCMCI), Tehran University of Medical Sciences, Tehran, Iran aut Lahooti Afsaneh Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran aut Gruettner Cordula Micromod Partikeltechnologie GmbH, Friedrich-Barnewitz-Str. 4, 18119, Rostock, Germany aut Oghabian Mohammad Biomolecular Imaging Analysis Group (BIAG), Research Center for Molecular and Cellular Imaging (RCMCI), Tehran University of Medical Sciences, Tehran, Iran aut Applied Magnetic Resonance Springer Vienna 46/6(2015-06-01), 685-692 0937-9347 46:6<685 2015 46 723 https://doi.org/10.1007/s00723-015-0667-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00723-015-0667-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Najafian Nastaran Biomolecular Imaging Analysis Group (BIAG), Research Center for Molecular and Cellular Imaging (RCMCI), Tehran University of Medical Sciences, Tehran, Iran aut NATIONALLICENCE 700 1- Shanehsazzadeh Saeed Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran aut NATIONALLICENCE 700 1- Hajesmaeelzadeh Farzaneh Biomolecular Imaging Analysis Group (BIAG), Research Center for Molecular and Cellular Imaging (RCMCI), Tehran University of Medical Sciences, Tehran, Iran aut NATIONALLICENCE 700 1- Lahooti Afsaneh Department of Medical Physics and Biomedical Engineering, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran aut NATIONALLICENCE 700 1- Gruettner Cordula Micromod Partikeltechnologie GmbH, Friedrich-Barnewitz-Str. 4, 18119, Rostock, Germany aut NATIONALLICENCE 700 1- Oghabian Mohammad Biomolecular Imaging Analysis Group (BIAG), Research Center for Molecular and Cellular Imaging (RCMCI), Tehran University of Medical Sciences, Tehran, Iran aut NATIONALLICENCE 773 0- Applied Magnetic Resonance Springer Vienna 46/6(2015-06-01), 685-692 0937-9347 46:6<685 2015 46 723