51
|
Kovtunov KV, Barskiy DA, Coffey AM, Truong ML, Salnikov OG, Khudorozhkov AK, Inozemtseva EA, Prosvirin IP, Bukhtiyarov VI, Waddell KW, Chekmenev EY, Koptyug IV. High-resolution 3D proton MRI of hyperpolarized gas enabled by parahydrogen and Rh/TiO2 heterogeneous catalyst. Chemistry 2014; 20:11636-9. [PMID: 24961814 DOI: 10.1002/chem.201403604] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Indexed: 11/11/2022]
Abstract
Several supported metal catalysts were synthesized, characterized, and tested in heterogeneous hydrogenation of propene with parahydrogen to maximize nuclear spin hyperpolarization of propane gas using parahydrogen induced polarization (PHIP). The Rh/TiO2 catalyst with a metal particle size of 1.6 nm was found to be the most active and effective in the pairwise hydrogen addition and robust, demonstrating reproducible results with multiple hydrogenation experiments and stability for ≥1.5 years. 3D (1) H magnetic resonance imaging (MRI) of 1 % hyperpolarized flowing gas with microscale spatial resolution (625×625×625 μm(3) ) and large imaging matrix (128×128×32) was demonstrated by using a preclinical 4.7 T scanner and 17.4 s imaging scan time.
Collapse
Affiliation(s)
- Kirill V Kovtunov
- Laboratory of Magnetic Resonance Microimaging, International Tomography Center, SB RAS, 3A Institutskaya St., Novosibirsk 630090 (Russia) and Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090 (Russia).
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
52
|
Nikolaou P, Coffey AM, Ranta K, Walkup LL, Gust BM, Barlow MJ, Rosen MS, Goodson BM, Chekmenev EY. Multidimensional mapping of spin-exchange optical pumping in clinical-scale batch-mode 129Xe hyperpolarizers. J Phys Chem B 2014; 118:4809-16. [PMID: 24731261 PMCID: PMC4055050 DOI: 10.1021/jp501493k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
![]()
We present a systematic, multiparameter
study of Rb/129Xe spin-exchange optical pumping (SEOP)
in the regimes of high xenon
pressure and photon flux using a 3D-printed, clinical-scale stopped-flow
hyperpolarizer. In situ NMR detection was used to study the dynamics
of 129Xe polarization as a function of SEOP-cell operating
temperature, photon flux, and xenon partial pressure to maximize 129Xe polarization (PXe). PXe values of 95 ± 9%, 73 ± 4%, 60
± 2%, 41 ± 1%, and 31 ± 1% at 275, 515, 1000, 1500,
and 2000 Torr Xe partial pressure were achieved. These PXe polarization values were separately validated by ejecting
the hyperpolarized 129Xe gas and performing low-field MRI
at 47.5 mT. It is shown that PXe in this
high-pressure regime can be increased beyond already record levels
with higher photon flux and better SEOP thermal management, as well
as optimization of the polarization dynamics, pointing the way to
further improvements in hyperpolarized 129Xe production
efficiency.
Collapse
Affiliation(s)
- Panayiotis Nikolaou
- Department of Radiology, Vanderbilt University Institute of Imaging Science (VUIIS) , Nashville, Tennessee 37232, United States
| | | | | | | | | | | | | | | | | |
Collapse
|
53
|
Nikolaou P, Coffey AM, Walkup LL, Gust BM, Whiting N, Newton H, Muradyan I, Dabaghyan M, Ranta K, Moroz GD, Rosen MS, Patz S, Barlow MJ, Chekmenev EY, Goodson BM. XeNA: an automated 'open-source' (129)Xe hyperpolarizer for clinical use. Magn Reson Imaging 2014; 32:541-50. [PMID: 24631715 DOI: 10.1016/j.mri.2014.02.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 01/30/2014] [Accepted: 02/02/2014] [Indexed: 11/28/2022]
Abstract
Here we provide a full report on the construction, components, and capabilities of our consortium's "open-source" large-scale (~1L/h) (129)Xe hyperpolarizer for clinical, pre-clinical, and materials NMR/MRI (Nikolaou et al., Proc. Natl. Acad. Sci. USA, 110, 14150 (2013)). The 'hyperpolarizer' is automated and built mostly of off-the-shelf components; moreover, it is designed to be cost-effective and installed in both research laboratories and clinical settings with materials costing less than $125,000. The device runs in the xenon-rich regime (up to 1800Torr Xe in 0.5L) in either stopped-flow or single-batch mode-making cryo-collection of the hyperpolarized gas unnecessary for many applications. In-cell (129)Xe nuclear spin polarization values of ~30%-90% have been measured for Xe loadings of ~300-1600Torr. Typical (129)Xe polarization build-up and T1 relaxation time constants were ~8.5min and ~1.9h respectively under our spin-exchange optical pumping conditions; such ratios, combined with near-unity Rb electron spin polarizations enabled by the high resonant laser power (up to ~200W), permit such high PXe values to be achieved despite the high in-cell Xe densities. Importantly, most of the polarization is maintained during efficient HP gas transfer to other containers, and ultra-long (129)Xe relaxation times (up to nearly 6h) were observed in Tedlar bags following transport to a clinical 3T scanner for MR spectroscopy and imaging as a prelude to in vivo experiments. The device has received FDA IND approval for a clinical study of chronic obstructive pulmonary disease subjects. The primary focus of this paper is on the technical/engineering development of the polarizer, with the explicit goals of facilitating the adaptation of design features and operative modes into other laboratories, and of spurring the further advancement of HP-gas MR applications in biomedicine.
Collapse
Affiliation(s)
- Panayiotis Nikolaou
- Department of Radiology, Vanderbilt University Institute of Imaging Science (VUIIS), Nashville, TN, 37232, United States; Department of Chemistry & Biochemistry, Southern Illinois University, Carbondale, IL.
| | - Aaron M Coffey
- Department of Radiology, Vanderbilt University Institute of Imaging Science (VUIIS), Nashville, TN, 37232, United States; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, United States
| | - Laura L Walkup
- Department of Chemistry & Biochemistry, Southern Illinois University, Carbondale, IL
| | - Brogan M Gust
- Department of Chemistry & Biochemistry, Southern Illinois University, Carbondale, IL
| | - Nicholas Whiting
- Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, NG7 2RD, Nottingham, UK
| | - Hayley Newton
- Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, NG7 2RD, Nottingham, UK
| | - Iga Muradyan
- Department of Radiology, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
| | - Mikayel Dabaghyan
- Department of Radiology, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
| | - Kaili Ranta
- Department of Physics, Southern Illinois University, Carbondale, IL
| | - Gregory D Moroz
- Graduate School Central Research Shop, Southern Illinois University, Carbondale, IL
| | - Matthew S Rosen
- MGH/A.A. Martinos Center for Biomedical Imaging, Boston, MA; Department of Physics, Harvard University, Cambridge, MA
| | - Samuel Patz
- Department of Radiology, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
| | - Michael J Barlow
- Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, NG7 2RD, Nottingham, UK
| | - Eduard Y Chekmenev
- Department of Radiology, Vanderbilt University Institute of Imaging Science (VUIIS), Nashville, TN, 37232, United States; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, United States; Department of Biochemistry, Vanderbilt University, Nashville, TN, 37205, United States
| | - Boyd M Goodson
- Department of Chemistry & Biochemistry, Southern Illinois University, Carbondale, IL.
| |
Collapse
|