Making SABRE Enhanced Low-Field NMR Experiments Accessible to Modern Research Labs; The Academic and Social Consequences of Multidisciplinary Laboratory Structure in the Context of Dr. Warren Warren's Laboratory at Duke University 356 views

Magnetic Resonance Imaging (MRI) is an important and rapidly developing clinical imaging technique. However, it is fundamentally limited by low signal intensities which makes large magnetic fields necessary to produce clear images. Traditionally this low sensitivity has been addressed by using increasingly large magnetic fields to generate signal. However, because of high cost of care and acquisition and rapidly depleting cryogen resources for cooling these powerful magnets, lower field alternatives are being investigated. Low field imagers would be less costly for hospitals to purchase and maintain and would increase access to the powerful diagnostic information available with this imaging technique. Advances in post-acquisition processing and pre-acquisition sample preparation have expanded the possibilities of using low field MRI in a clinical setting. Here, I focus on improving the accessibility of a newly introduced hyperpolarization technique which creates large spin polarizations and therefore large MR signals without the need for high magnetic fields: Signal Amplification By Reversible Exchange (SABRE). SABRE hyperpolarization uses an iridium catalyst to connect highly polarized parahydrogen with a target nucleus to transfer polarization from the parahydrogen spin state to the target. This technique is complicated by many experimental variables which can be difficult to experimentally optimize. By creating a user interface for a newly introduced numerical simulation package which accurately predicts polarization dynamics in SABRE experiments and coupling that interface with a rigorously reproducible electromagnet coil array, I establish an experimental protocol which makes low-field SABRE experiments more easily accessible and less variable for use in any basic Nuclear Magnetic Resonance (NMR) laboratory. This apparatus and theoretical optimization of NMR pulse parameters opens up the opportunity to increase the scientific inquiry into this relatively young hyperpolarization technique with the aim of improving our understanding of this regime and moving towards clinical applications. Most labs are structured in a way that encourages a variety of research categorized under the same discipline. However, Dr. Warren Warren’s lab at Duke University somewhat breaks this typical structure by consisting of two groups performing research into different phenomena. One subgroup of the lab does research into laser spectroscopy, and the other subgroup does research into NMR spectroscopy. Research into Dr. Warren’s history and the development of the lab structure yielded insight into the merits it provides, and investigation into the lab philosophy was performed to explore the motivations behind it. Surveys and interviews were performed with lab members to reveal member experiences with the lab structure. In the STS research paper, the dynamics between the mostly autonomous groups and the benefits of this configuration are explored using Actor-Network Theory and Social Identity Theory as social frameworks.

BS (Bachelor of Science)

MRI; NMR; Magnetic Resonance; Hyperpolarization; Low Field; Clinical Imaging

School of Engineering and Applied Science Bachelor of Science in Biomedical Engineering Technical Advisor: Warren Warren STS Advisor: Tsai-Hsuan Ku Technical Team Members: Clark Eriksson

English

All rights reserved (no additional license for public reuse)

2021-05-20