Co‐acquisition of hyperpolarised ¹³C and ¹⁵N NMR spectra

Abstract

Recent developments in dynamic nuclear polarisation now allow significant enhancements to be generated in the cryo solid state and transferred to the liquid state for detection at high resolution. We demonstrate that the Ardenkjaer-Larsen method can be extended by taking advantage of the properties of the trityl radicals used. It is possible to hyperpolarise 13C and 15N simultaneously in the solid state, and to maintain these hyperpolarisations through rapid dissolution into the liquid state. We demonstrate the almost simultaneous measurement of hyperpolarised 13C and hyperpolarised 15N NMR spectra. The prospects for further improvement of the method using contemporary technology are also discussed.

Progress in Hyperpolarized Ultrafast 2D NMR Spectroscopy

“…As shown by Day et al it is then possible to exploit the hyperpolarization experienced by both species, one after the other, within the same pumping cycle. [36] Motivated by this observation, Figure 8 illustrates the performance of two consecutive ultrafast 2D NMR experiments based on the same hyperpolarized sample, but starting on the different heteronuclei present in a labeled urea molecule. Since the signal enhancement is usually lower for 15 N than for its 13 C counterpart, we began these measurements with a 15 N-triggered HSQC to H ultrafast 2D correlation to complete two one-bond transfers.…”

Inhomogeneity-free heteronuclear iMQC

“…Many different research groups have been examining potential uses of such hyperpolarized molecules both in vivo and in vitro (11–14). The DNP methodology, in particular, is very versatile, and hundreds of different molecules have been polarized.…”

Improved Stability and Spectral Quality in Ex Situ Dissolution DNP Using an Improved Transfer Device

“…d-f SSFT data from a-c fitted using Eq. 8 from [4] to calculate a T 1 relaxation time dimension and thus resolve details of the peak shapes. Considering the faster transfer it was also possible to acquire additional increments, thus improving the resolution in the indirect dimension.…”

“…Considering the faster transfer it was also possible to acquire additional increments, thus improving the resolution in the indirect dimension. In order to demonstrate the increased stability achieved, we carried out SSTF longitudinal relaxation time measurements using Day's method [4] (Fig. 3).…”

“…Longitudinal relaxation measurements were carried out as described by Day et al [4], using the single-scan FT (SSFT) method originally proposed by Kaptein [5]. A train of 308 pulses was employed, spaced 2 s apart with data acquisition during the first 500 ms of this period with a spectral width of 250 ppm.…”