Pilot multi-site quality assurance study of batch-mode clinical-scale automated xenon-129 hyperpolarizers

Enabling Clinical Technologies for Hyperpolarized 129Xenon Magnetic Resonance Imaging and Spectroscopy

“…In this study, the repeatability of SEOP in a 1000 torr Xe/900 torr N 2 /100 torr 4 He (2000 torr total pressure) gas mixture was investigated over several hundred gas‐loading cycles, with very little decrease in performance during the first ≈200 cycles: P Xe =71.7±1.5 %, γ SEOP =0.019±0.003 min −1 , 129 Xe T 1 =90.5±10.3 min. Although the SEOP cell in this study exhibited a detectable performance decrease after 400 cycles, the cell continued to produce potentially useable P Xe =42.3±0.6 % even after nearly 700 refill cycles [72] . The ability to reproducibly achieve and maintain performance over so many refill cycles without having to replace the SEOP cell bodes well for the ultimate translation of the device to biomedical and clinical imaging applications.…”

“…Display (a) reproduced with permission from ref. [72]; Displays (b,c) reproduced with permission from ref. [73].…”

“…[76]; Display (c) is reproduced with permission from ref. [72]. Gas mixture compositions are listed in units of torr.…”

Enabling Clinical Technologies for Hyperpolarized 129Xenon Magnetic Resonance Imaging and Spectroscopy

“…Although the SEOP cell in this study exhibited ad etectable performance decrease after 400 cycles,t he cell continued to produce potentially useable P Xe = 42.3 AE 0.6 % even after nearly 700 refill cycles. [72] Thea bility to reproducibly achieve and maintain performance over so many refill cycles without having to replace the SEOP cell bodes well for the ultimate translation of the device to biomedical and clinical imaging applications.…”

Binding site exchange kinetics revealed through efficient spin–spin dephasing of hyperpolarized129Xe

“…A conservative extrapolation of what sensitivity might be reachable is the following: unlocalized NMR requires less dissolved Xe and should presumably work with at least 100-fold reduced concentrations of what was used in this study (this is also supported by recent reports of optimized polarizers that easily achieve 3-fold higher polarization than the setup used here). 47 The bulk pool could thus be reduced to 20 mM of dissolved Xe (which is comparable to the HP ligand concentration in the 19 F DNP study). The same f B of 8 Â 10 À5 would then correspond to 1.6 nM for the analyte that induces the exchange relaxation (in a single-shot spin echo train acquisition).…”