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Updated: May 21, 2026
11:43
Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
Generating contrast in hyperpolarized 13C MRI using ligand-receptor interactions.
Kayvan R Keshari1, John Kurhanewicz, Jeffrey M Macdonald
1Department of Radiology, University of California San Francisco, San Francisco, USA.
The Analyst
|June 2, 2012
Summary
This study visualizes β-cyclodextrin-benzoic acid interactions using hyperpolarized carbon-13 magnetic resonance (MR) at 14T. The findings suggest potential for in vivo receptor density determination with this advanced MR technique.
Area of Science:
- Biophysical Chemistry
- Magnetic Resonance Imaging
- Molecular Recognition
Background:
- Investigating molecular interactions is crucial for understanding biological processes.
- Magnetic Resonance (MR) offers non-invasive imaging capabilities.
- Hyperpolarization techniques enhance MR signal sensitivity.
Purpose of the Study:
- To image the binding of β-cyclodextrin with benzoic acid using hyperpolarized (13)C MR.
- To assess the feasibility of quantifying ligand-receptor interactions in situ.
- To explore the potential of this method for in vivo applications.
Main Methods:
- Dynamic Nuclear Polarization (DNP) was used to hyperpolarize [1-(13)C] benzoic acid.
- Binding studies were conducted in aqueous solutions with varying β-cyclodextrin concentrations.
- High-field (14T) 3D frequency-selective MR imaging was employed.
Main Results:
- Observed decreases in spin-lattice relaxation (T(1)) correlated with ligand-receptor ratios.
- Calculated binding constant (log K) was approximately 1.7, consistent with literature values.
- Differences in β-cyclodextrin concentration were clearly visualized via MR imaging.
Conclusions:
- Hyperpolarized (13)C MR can effectively image β-cyclodextrin-benzoic acid binding.
- The technique demonstrates sensitivity to varying concentrations of binding partners.
- This approach holds promise for in vivo determination of receptor presence and density.
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