NMR relaxation in systems with magnetic nanoparticles

A temperature study

Bashar Issa, Ihab M. Obaidat, Rola H. Hejasee, Shahnaz Qadri, Yousef Haik

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Purpose To measure and model nuclear magnetic resonance (NMR) relaxation enhancement due to the presence of gadolinium (Gd)-substituted Zn-Mn ferrite magnetic nanoparticles (MNP) at different temperatures. Materials and Methods Relaxation rates were measured at 1.5 T using fast spin echo (FSE) sequences in samples of agarose gel doped with uncoated and polyethylene glycol (PEG)-coated Mn0.5Zn0.5Gd0.02Fe1.98O4 nanoparticles over the temperature range 8-58°C. Physical characterization of the MNPs synthesized using chemical coprecipitation included scanning (SEM) and transmission (TEM) electron microscopy, inductively coupled plasma (ICP), dynamic light scattering (DLS), and magnetometry. Results Relaxivity (in s -1 mM-1 Fe) for the uncoated and coated particles, respectively, increased as follows: from 2.5 to 3.2 and 0.4 to 0.7 for T1, while for T2 it increased from 162.3 to 253.7 and 59.7 to 82.2 over the temperature range 8-58°C. T2 data were fitted to the echo limited motional regime using one fitting parameter that reflects the degree of agglomeration of particles into a cluster. This parameter was found to increase linearly with temperature and was larger for the PEG-coated particles than the uncoated ones. Conclusion The increase of 1/T2 with temperature is modeled successfully using echo limited motional regime where both diffusion of the protons and nanoparticle cluster size increase with temperature. Both transverse and longitudinal relaxation efficiencies are reduced by PEG coating at all temperatures. If prediction of relaxation rates under different particle concentrations and operating temperatures is possible then the use of MNP in temperature monitoring and hyperthermia applications may be achieved. J. Magn. Reson. Imaging 2014;39:648-655. © 2013 Wiley Periodicals, Inc.

Original languageEnglish
Pages (from-to)648-655
Number of pages8
JournalJournal of Magnetic Resonance Imaging
Volume39
Issue number3
DOIs
Publication statusPublished - Mar 2014
Externally publishedYes

Fingerprint

Nanoparticles
Magnetic Resonance Spectroscopy
Temperature
Magnetometry
Gadolinium
Transmission Electron Microscopy
Sepharose
Protons
Fever
Gels

Keywords

  • agglomeration
  • coating
  • contrast agents
  • hyperthermia
  • nanoparticles
  • NMR relaxation

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Medicine(all)

Cite this

NMR relaxation in systems with magnetic nanoparticles : A temperature study. / Issa, Bashar; Obaidat, Ihab M.; Hejasee, Rola H.; Qadri, Shahnaz; Haik, Yousef.

In: Journal of Magnetic Resonance Imaging, Vol. 39, No. 3, 03.2014, p. 648-655.

Research output: Contribution to journalArticle

Issa, Bashar ; Obaidat, Ihab M. ; Hejasee, Rola H. ; Qadri, Shahnaz ; Haik, Yousef. / NMR relaxation in systems with magnetic nanoparticles : A temperature study. In: Journal of Magnetic Resonance Imaging. 2014 ; Vol. 39, No. 3. pp. 648-655.
@article{0e548c7c713a46449476dff67a5eac9c,
title = "NMR relaxation in systems with magnetic nanoparticles: A temperature study",
abstract = "Purpose To measure and model nuclear magnetic resonance (NMR) relaxation enhancement due to the presence of gadolinium (Gd)-substituted Zn-Mn ferrite magnetic nanoparticles (MNP) at different temperatures. Materials and Methods Relaxation rates were measured at 1.5 T using fast spin echo (FSE) sequences in samples of agarose gel doped with uncoated and polyethylene glycol (PEG)-coated Mn0.5Zn0.5Gd0.02Fe1.98O4 nanoparticles over the temperature range 8-58°C. Physical characterization of the MNPs synthesized using chemical coprecipitation included scanning (SEM) and transmission (TEM) electron microscopy, inductively coupled plasma (ICP), dynamic light scattering (DLS), and magnetometry. Results Relaxivity (in s -1 mM-1 Fe) for the uncoated and coated particles, respectively, increased as follows: from 2.5 to 3.2 and 0.4 to 0.7 for T1, while for T2 it increased from 162.3 to 253.7 and 59.7 to 82.2 over the temperature range 8-58°C. T2 data were fitted to the echo limited motional regime using one fitting parameter that reflects the degree of agglomeration of particles into a cluster. This parameter was found to increase linearly with temperature and was larger for the PEG-coated particles than the uncoated ones. Conclusion The increase of 1/T2 with temperature is modeled successfully using echo limited motional regime where both diffusion of the protons and nanoparticle cluster size increase with temperature. Both transverse and longitudinal relaxation efficiencies are reduced by PEG coating at all temperatures. If prediction of relaxation rates under different particle concentrations and operating temperatures is possible then the use of MNP in temperature monitoring and hyperthermia applications may be achieved. J. Magn. Reson. Imaging 2014;39:648-655. {\circledC} 2013 Wiley Periodicals, Inc.",
keywords = "agglomeration, coating, contrast agents, hyperthermia, nanoparticles, NMR relaxation",
author = "Bashar Issa and Obaidat, {Ihab M.} and Hejasee, {Rola H.} and Shahnaz Qadri and Yousef Haik",
year = "2014",
month = "3",
doi = "10.1002/jmri.24197",
language = "English",
volume = "39",
pages = "648--655",
journal = "Journal of Magnetic Resonance Imaging",
issn = "1053-1807",
publisher = "John Wiley and Sons Inc.",
number = "3",

}

TY - JOUR

T1 - NMR relaxation in systems with magnetic nanoparticles

T2 - A temperature study

AU - Issa, Bashar

AU - Obaidat, Ihab M.

AU - Hejasee, Rola H.

AU - Qadri, Shahnaz

AU - Haik, Yousef

PY - 2014/3

Y1 - 2014/3

N2 - Purpose To measure and model nuclear magnetic resonance (NMR) relaxation enhancement due to the presence of gadolinium (Gd)-substituted Zn-Mn ferrite magnetic nanoparticles (MNP) at different temperatures. Materials and Methods Relaxation rates were measured at 1.5 T using fast spin echo (FSE) sequences in samples of agarose gel doped with uncoated and polyethylene glycol (PEG)-coated Mn0.5Zn0.5Gd0.02Fe1.98O4 nanoparticles over the temperature range 8-58°C. Physical characterization of the MNPs synthesized using chemical coprecipitation included scanning (SEM) and transmission (TEM) electron microscopy, inductively coupled plasma (ICP), dynamic light scattering (DLS), and magnetometry. Results Relaxivity (in s -1 mM-1 Fe) for the uncoated and coated particles, respectively, increased as follows: from 2.5 to 3.2 and 0.4 to 0.7 for T1, while for T2 it increased from 162.3 to 253.7 and 59.7 to 82.2 over the temperature range 8-58°C. T2 data were fitted to the echo limited motional regime using one fitting parameter that reflects the degree of agglomeration of particles into a cluster. This parameter was found to increase linearly with temperature and was larger for the PEG-coated particles than the uncoated ones. Conclusion The increase of 1/T2 with temperature is modeled successfully using echo limited motional regime where both diffusion of the protons and nanoparticle cluster size increase with temperature. Both transverse and longitudinal relaxation efficiencies are reduced by PEG coating at all temperatures. If prediction of relaxation rates under different particle concentrations and operating temperatures is possible then the use of MNP in temperature monitoring and hyperthermia applications may be achieved. J. Magn. Reson. Imaging 2014;39:648-655. © 2013 Wiley Periodicals, Inc.

AB - Purpose To measure and model nuclear magnetic resonance (NMR) relaxation enhancement due to the presence of gadolinium (Gd)-substituted Zn-Mn ferrite magnetic nanoparticles (MNP) at different temperatures. Materials and Methods Relaxation rates were measured at 1.5 T using fast spin echo (FSE) sequences in samples of agarose gel doped with uncoated and polyethylene glycol (PEG)-coated Mn0.5Zn0.5Gd0.02Fe1.98O4 nanoparticles over the temperature range 8-58°C. Physical characterization of the MNPs synthesized using chemical coprecipitation included scanning (SEM) and transmission (TEM) electron microscopy, inductively coupled plasma (ICP), dynamic light scattering (DLS), and magnetometry. Results Relaxivity (in s -1 mM-1 Fe) for the uncoated and coated particles, respectively, increased as follows: from 2.5 to 3.2 and 0.4 to 0.7 for T1, while for T2 it increased from 162.3 to 253.7 and 59.7 to 82.2 over the temperature range 8-58°C. T2 data were fitted to the echo limited motional regime using one fitting parameter that reflects the degree of agglomeration of particles into a cluster. This parameter was found to increase linearly with temperature and was larger for the PEG-coated particles than the uncoated ones. Conclusion The increase of 1/T2 with temperature is modeled successfully using echo limited motional regime where both diffusion of the protons and nanoparticle cluster size increase with temperature. Both transverse and longitudinal relaxation efficiencies are reduced by PEG coating at all temperatures. If prediction of relaxation rates under different particle concentrations and operating temperatures is possible then the use of MNP in temperature monitoring and hyperthermia applications may be achieved. J. Magn. Reson. Imaging 2014;39:648-655. © 2013 Wiley Periodicals, Inc.

KW - agglomeration

KW - coating

KW - contrast agents

KW - hyperthermia

KW - nanoparticles

KW - NMR relaxation

UR - http://www.scopus.com/inward/record.url?scp=84894062699&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84894062699&partnerID=8YFLogxK

U2 - 10.1002/jmri.24197

DO - 10.1002/jmri.24197

M3 - Article

VL - 39

SP - 648

EP - 655

JO - Journal of Magnetic Resonance Imaging

JF - Journal of Magnetic Resonance Imaging

SN - 1053-1807

IS - 3

ER -