MRI sensing based on the displacement of paramagnetic ions from chelated complexes
Name
Jasanoff-2010-MRI sensing based.pdf
Size
411.11 KB
Format
Adobe PDF
Checksum (MD5)
9d536527b08262ba5937f1fd0ce4da7c
Author(s)
Atanasijevic, Tatjana
Zhang, Xiao-an
Lippard, Stephen J.
Jasanoff, Alan Pradip
Date Issued
March 2010
Journal
Inorganic Chemistry
Publisher
American Chemical Society
Citation
Atanasijevic, Tatjana et al. “MRI Sensing Based on the Displacement of Paramagnetic Ions from Chelated Complexes.” Inorganic Chemistry 49 (2010): 2589-2591. Web. 28 Oct. 2011. © 2010 American Chemical Society
Version
Author's final manuscript
Abstract
We introduce a mechanism for ion sensing by MRI in which analytes compete with paramagnetic ions for binding to polydentate chelating agents. Displacement of the paramagnetic ions results in alteration of solvent interaction parameters and consequent changes in relaxivity and MRI contrast. The MRI changes can be tuned by the choice of chelator. As an example, we show that calcium-dependent displacement of Mn[superscript 2+] ions bound to EGTA and BAPTA results in a T[subscript 1]-weighted MRI signal increase, whereas displacement from calmodulin results in a signal decrease. The changes are ion selective and can be explained using relaxivity theory. The ratio of T[subscript 2] to T[subscript 1] relaxivity is also calcium-dependent, indicating the feasibility of “ratiometric” analyte detection, independent of the probe concentration. Measurement of paramagnetic ion displacement effects could be used to determine analyte ion concentrations with spatial resolution in opaque specimens.
MIT Department
Massachusetts Institute of Technology. Department of Biological Engineering
Massachusetts Institute of Technology. Department of Chemistry
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike 3.0
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1021/ic100150e
