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Updated: Jun 3, 2026
05:15
An Aptamer-based Sensor for Unchelated Gadolinium(III)
Published on: January 9, 2017
Relaxivity of gadolinium complexes detected by atomic magnetometry
David J Michalak1, Shoujun Xu, Thomas J Lowery
1Materials Sciences Division, Lawrence Berkeley National Laboratory, Department of Chemistry, University of California, Berkeley, California, USA.
Magnetic Resonance in Medicine
|March 25, 2011
Summary
Laser atomic magnetometry offers sensitive, portable detection of low magnetic fields. This study measured gadolinium diethylenetriamine pentaacetic acid (Gd(DTPA)) relaxivity at Earth's field, demonstrating potential for medical applications.
Area of Science:
- Physics
- Chemistry
- Biomedical Engineering
Background:
- Laser atomic magnetometry provides a portable and cost-effective approach for highly sensitive low magnetic field detection.
- Gadolinium-based contrast agents (GBCAs) are crucial in Magnetic Resonance Imaging (MRI), but their relaxivity can be field-dependent.
- Measuring relaxivity at Earth's magnetic field is important for understanding GBCA behavior in physiological conditions.
Purpose of the Study:
- To measure the relaxivity of aqueous gadolinium-diethylenetriamine pentaacetic acid (Gd(DTPA)) using laser atomic magnetometry at Earth's magnetic field.
- To assess the feasibility of using portable atomic magnetometry for characterizing GBCAs in a remote-detection setup.
- To evaluate the potential of this technique for medical applications requiring sensitive detection of low concentrations of Gd-based agents.
Main Methods:
- Utilized a laser atomic magnetometer in a remote-detection geometry.
- Measured the relaxivity of Gd(DTPA) in an aqueous buffer solution at Earth's magnetic field (approximately 40 μT).
- Achieved a field-independent sensitivity of 80 fT Hz(-1/2).
Main Results:
- The measured relaxivity of Gd(DTPA) was 9.7±2.0 s(-1) mM(-1) at Earth's magnetic field.
- This result is consistent with previous field-cycling experiments conducted at slightly higher magnetic fields.
- An in vitro detection limit of approximately 10 μM Gd(DTPA) was achieved.
- The experiment did not require cryogens or strong, homogeneous magnetic fields.
Conclusions:
- Laser atomic magnetometry is a viable technique for measuring Gd(DTPA) relaxivity at Earth's magnetic field without specialized equipment.
- The demonstrated low detection limit and sensitivity highlight the potential of atomic magnetometry for medical diagnostics and research.
- Further development of atomic magnetometry could lead to advanced portable devices for characterizing MRI contrast agents and other biomedical applications.
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