A low-field ceramic magnet design for magnetic resonance

Devin M Morin; Sebastian Richard; Naser Ansaribaranghar; Benedict Newling; Bruce J Balcom

doi:10.1016/j.jmr.2023.107599

A low-field ceramic magnet design for magnetic resonance

J Magn Reson. 2024 Jan:358:107599. doi: 10.1016/j.jmr.2023.107599. Epub 2023 Nov 23.

Authors

Devin M Morin¹, Sebastian Richard¹, Naser Ansaribaranghar¹, Benedict Newling¹, Bruce J Balcom²

Affiliations

¹ UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton E3B 5A3, Canada.
² UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton E3B 5A3, Canada. Electronic address: bjb@unb.ca.

PMID: 38041994
DOI: 10.1016/j.jmr.2023.107599

Abstract

We describe the design of a low-field portable magnet, based on two ceramic magnets, separated by a distance, with their magnetic poles aligned to create a large homogeneous region with a field strength of 425 gauss. Ceramic magnets are an uncommon choice compared to Neodymium Iron Boron magnets for low-field magnetic resonance but are preferable for our purposes to create a homogeneous region at lower field strength. The low cost of large ceramic magnets results in an inexpensive design with a large measurement volume. The magnets rest in a 3D-printed structure, which allows for the magnets to be moved by hand so the experimentalist has control over the field topology. To test the utility of the design, we explored an Overhauser dynamic nuclear polarization experiment with an aqueous solution of 4-Hydroxy-TEMPO. We also explored a simple flow measurement employing the ceramic magnets at a 6-degree pitch, creating a 14.6 gauss/cm constant gradient.

Keywords: CLAM; DNP; Flow; Low-Field; Magnet Design; Overhauser; Permanent Magnet; Portable MR.