Using frequency-narrowed, tunable laser diode arrays with integrated volume holographic gratings for spin-exchange optical pumping at high resonant fluxes and xenon densities

Whiting, Nicholas; Nikolaou, Panayiotis; Eschmann, Neil A.; Barlow, Michael J.; Lammert, R.M.; Ungar, J.; Hu, Wentao; Vaissie, Laurent; Goodson, Boyd M.

doi:10.1007/s00340-012-4924-x

Cited by 37 publications

(41 citation statements)

References 43 publications

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“…Control of the cell temperature is also key for SEOP optimization. Previously, it was shown that there can be an inverse relationship between Xe density and the optimal temperature for SEOP, where higher [Xe] favors lower cell temperatures (22,29)-an effect that may be explained in part by the need to maintain uniform illumination throughout the cell. Although γ SE is proportional to the Rb density (34)-ostensibly favoring higher cell temperatures-maintaining a high "photon-to-Rb" ratio (in part by limiting [Rb]) can be particularly important for preserving global 〈P Rb 〉 as Xe density is increased, and Xe-induced Rb spin-destruction becomes dominant.…”

Section: Discussionmentioning

confidence: 99%

“…The performance of the polarizer is the result of a number of aspects of the SEOP process that are both fundamental and technical in nature (29). SEOP can be treated as a simple relaxation process (23), which at steady state, simplifies to give the following (15):…”

Section: Discussionmentioning

confidence: 99%

“…The optical path (Fig. 1B) begins with a 200-W laser diode array (QPC Lasers) that produces tunable, frequency-narrowed (29) laser output at the Rb D 1 line (∼794.8 nm; nominal FWHM, ∼0.27 nm). The laser beam passes through an optical fiber and expands to 2-inch diameter before collimation and entrance into a polarizing beam-splitter (PBS).…”

Section: Methodsmentioning

confidence: 99%

“…In our recent work (22,28,29) exploring Rb/Xe SEOP under conditions of high resonant laser flux, an inverse relationship was found between the optimal temperature and the in-cell Xe density. This effect was exploited to achieve surprisingly high P Xe values at high Xe densities (e.g., ∼52%, ∼22%, and ∼11% at 50, 500, and 2,000 torr Xe in a 75-cc cell) with <30 W of laser power (22).…”

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confidence: 99%

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Near-unity nuclear polarization with an open-source ¹²⁹ Xe hyperpolarizer for NMR and MRI

Nikolaou

Coffey

Walkup

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

207

262

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The exquisite NMR spectral sensitivity and negligible reactivity of hyperpolarized xenon-129 (HP 129 Xe) make it attractive for a number of magnetic resonance applications; moreover, HP 129 Xe embodies an alternative to rare and nonrenewable 3 He. However, the ability to reliably and inexpensively produce large quantities of HP 129 Xe with sufficiently high 129 Xe nuclear spin polarization (P Xe ) remains a significant challenge-particularly at high Xe densities. We present results from our "open-source" large-scale (∼1 L/h) 129Xe polarizer for clinical, preclinical, and materials NMR and MRI research. Automated and composed mostly of off-the-shelf components, this "hyperpolarizer" is designed to be readily implementable in other laboratories. The device runs with high resonant photon flux (up to 200 W at the Rb D 1 line) in the xenon-rich regime (up to 1,800 torr Xe in 500 cc) in either single-batch or stopped-flow mode, negating in part the usual requirement of Xe cryocollection. Excellent agreement is observed among four independent methods used to measure spin polarization. In-cell P Xe values of ∼90%, ∼57%, ∼50%, and ∼30% have been measured for Xe loadings of ∼300, ∼500, ∼760, and ∼1,570 torr, respectively. P Xe values of ∼41% and ∼28% (with ∼760 and ∼1,545 torr Xe loadings) have been measured after transfer to Tedlar bags and transport to a clinical 3 T scanner for MR imaging, including demonstration of lung MRI with a healthy human subject. Long "in-bag"129 Xe polarization decay times have been measured (T 1 ∼38 min and ∼5.9 h at ∼1.5 mT and 3 T, respectively)-more than sufficient for a variety of applications.hyperpolarization | laser-polarized xenon | lung imaging | optical pumping O wing to the detection sensitivity provided by their high, nonequilibrium nuclear spin polarization, hyperpolarized (HP) noble gases (e.g., Xe is of particular interest. Moreover, xenon is soluble in blood (6), other tissues (7, 8), and many biologically compatible liquids (9), and its proclivity for interacting with other substances and its wide chemical shift range make HP 129 Xe a sensitive NMR probe of molecular and material surfaces (1,(10)(11)(12) Xe is usually created via spin-exchange optical pumping (SEOP) (23), whereby the unpaired electronic spins of an alkali metal vapor (e.g., Rb) are polarized via optical pumping with circularly polarized light, and the polarization is transferred to noble gas nuclear spins during collisions. It is generally anticipated that high P Xe is achievable only in the low xenon-density regime (18, 24), because (i) higher Xe densities increase the destruction of Rb polarization from nonspin-conserving collisions at a rate that is orders of magnitude worse than those of other gases like N 2 and He (25-27); and (ii) higher total pressures tend to quench the threebody van der Waals contribution to Rb-Xe spin exchange-leaving the less-efficient two-body term (18,23). Most large-scale polarizers, in particular all that are available commercially, operate in this low-Xe density ...

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

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Near-unity nuclear polarization with an open-source ¹²⁹ Xe hyperpolarizer for NMR and MRI

Nikolaou

Coffey

Walkup

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

207

262

View full text Add to dashboard Cite

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“…Volume holographic grating, VHGs, have been intensively investigated and developed for applications in spectroscopy. By narrowing the spectral output of high-power laserdiode arrays (LDA), it was possible to reach a 3-fold improvement in 129 Xe nuclear polarization even at high in-cell xenon densities [77,78]. In addition to the utility of VHG narrowed lasers, it was reported that there is an inverse relationship between the xenon partial pressure and the optimal cell temperature of the Rb/Xe SEOP.…”

Section: Other 129 Xe Polarizer Designsmentioning

confidence: 99%

129Xenon NMR: Review of recent insights into porous materials

Weiland

Springuel‐Huet

Nossov

et al. 2016

Microporous and Mesoporous Materials

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Microscale Hyperpolarization

Kiss

Bordonali

Korvink

et al. 2018

Micro and Nano Scale NMR

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Using frequency-narrowed, tunable laser diode arrays with integrated volume holographic gratings for spin-exchange optical pumping at high resonant fluxes and xenon densities

Cited by 37 publications

References 43 publications

Near-unity nuclear polarization with an open-source ¹²⁹ Xe hyperpolarizer for NMR and MRI

Near-unity nuclear polarization with an open-source ¹²⁹ Xe hyperpolarizer for NMR and MRI

129Xenon NMR: Review of recent insights into porous materials

Microscale Hyperpolarization

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Using frequency-narrowed, tunable laser diode arrays with integrated volume holographic gratings for spin-exchange optical pumping at high resonant fluxes and xenon densities

Cited by 37 publications

References 43 publications

Near-unity nuclear polarization with an open-source 129 Xe hyperpolarizer for NMR and MRI

Near-unity nuclear polarization with an open-source 129 Xe hyperpolarizer for NMR and MRI

129Xenon NMR: Review of recent insights into porous materials

Microscale Hyperpolarization

Contact Info

Product

Resources

About

Near-unity nuclear polarization with an open-source ¹²⁹ Xe hyperpolarizer for NMR and MRI

Near-unity nuclear polarization with an open-source ¹²⁹ Xe hyperpolarizer for NMR and MRI