Abstract
Gd(III) associated with carbon nanomaterials relaxes water proton spins at an effectiveness that approaches or exceeds the theoretical limit for a single bound water molecule. These Gd(III)-labeled materials represent a potential breakthrough in sensitivity for Gd(III)-based contrast agents used for magnetic resonance imaging (MRI). However, their mechanism of action remains unclear. A gadographene library encompassing GdCl3, two different Gd(III) complexes, graphene oxide (GO), and graphene suspended by two different surfactants and subjected to varying degrees of sonication was prepared and characterized for their relaxometric properties. Gadographene was found to perform comparably to other Gd(III)-carbon nanomaterials; its longitudinal (r1) and transverse (r2) relaxivity are modulated between 12-85 mM-1 s-1 and 24-115 mM-1 s-1, respectively, depending on the Gd(III)-carbon backbone combination. The unusually large relaxivity and its variance can be understood under the modified Florence model incorporating the Lipari-Szabo approach. Changes in hydration number (q), water residence time (τM), molecular tumbling rate (τR), and local motion (τfast) sufficiently explain most of the measured relaxivities. Furthermore, results implicated the coupling between graphene and Gd(III) as a minor contributor to proton spin relaxation.
| Original language | English |
|---|---|
| Pages (from-to) | 16263-16273 |
| Number of pages | 11 |
| Journal | Journal of Physical Chemistry C |
| Volume | 117 |
| Issue number | 31 |
| DOIs | |
| Publication status | Published - Aug 8 2013 |
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ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Energy(all)
Cite this
Mechanisms of gadographene-mediated proton spin relaxation. / Hung, Andy H.; Duch, Matthew C.; Parigi, Giacomo; Rotz, Matthew W.; Manus, Lisa M.; Mastarone, Daniel J.; Dam, Kevin T.; Gits, Colton C.; MacRenaris, Keith W.; Luchinat, Claudio; Hersam, Mark C.; Meade, Thomas J.
In: Journal of Physical Chemistry C, Vol. 117, No. 31, 08.08.2013, p. 16263-16273.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mechanisms of gadographene-mediated proton spin relaxation
AU - Hung, Andy H.
AU - Duch, Matthew C.
AU - Parigi, Giacomo
AU - Rotz, Matthew W.
AU - Manus, Lisa M.
AU - Mastarone, Daniel J.
AU - Dam, Kevin T.
AU - Gits, Colton C.
AU - MacRenaris, Keith W.
AU - Luchinat, Claudio
AU - Hersam, Mark C.
AU - Meade, Thomas J.
PY - 2013/8/8
Y1 - 2013/8/8
N2 - Gd(III) associated with carbon nanomaterials relaxes water proton spins at an effectiveness that approaches or exceeds the theoretical limit for a single bound water molecule. These Gd(III)-labeled materials represent a potential breakthrough in sensitivity for Gd(III)-based contrast agents used for magnetic resonance imaging (MRI). However, their mechanism of action remains unclear. A gadographene library encompassing GdCl3, two different Gd(III) complexes, graphene oxide (GO), and graphene suspended by two different surfactants and subjected to varying degrees of sonication was prepared and characterized for their relaxometric properties. Gadographene was found to perform comparably to other Gd(III)-carbon nanomaterials; its longitudinal (r1) and transverse (r2) relaxivity are modulated between 12-85 mM-1 s-1 and 24-115 mM-1 s-1, respectively, depending on the Gd(III)-carbon backbone combination. The unusually large relaxivity and its variance can be understood under the modified Florence model incorporating the Lipari-Szabo approach. Changes in hydration number (q), water residence time (τM), molecular tumbling rate (τR), and local motion (τfast) sufficiently explain most of the measured relaxivities. Furthermore, results implicated the coupling between graphene and Gd(III) as a minor contributor to proton spin relaxation.
AB - Gd(III) associated with carbon nanomaterials relaxes water proton spins at an effectiveness that approaches or exceeds the theoretical limit for a single bound water molecule. These Gd(III)-labeled materials represent a potential breakthrough in sensitivity for Gd(III)-based contrast agents used for magnetic resonance imaging (MRI). However, their mechanism of action remains unclear. A gadographene library encompassing GdCl3, two different Gd(III) complexes, graphene oxide (GO), and graphene suspended by two different surfactants and subjected to varying degrees of sonication was prepared and characterized for their relaxometric properties. Gadographene was found to perform comparably to other Gd(III)-carbon nanomaterials; its longitudinal (r1) and transverse (r2) relaxivity are modulated between 12-85 mM-1 s-1 and 24-115 mM-1 s-1, respectively, depending on the Gd(III)-carbon backbone combination. The unusually large relaxivity and its variance can be understood under the modified Florence model incorporating the Lipari-Szabo approach. Changes in hydration number (q), water residence time (τM), molecular tumbling rate (τR), and local motion (τfast) sufficiently explain most of the measured relaxivities. Furthermore, results implicated the coupling between graphene and Gd(III) as a minor contributor to proton spin relaxation.
UR - http://www.scopus.com/inward/record.url?scp=84881443919&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84881443919&partnerID=8YFLogxK
U2 - 10.1021/jp406909b
DO - 10.1021/jp406909b
M3 - Article
AN - SCOPUS:84881443919
VL - 117
SP - 16263
EP - 16273
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 31
ER -