Benchtop NMR spectrometers with sub-ppm spectral resolution have opened up new opportunities for performing NMR outside of the standard laboratory environment. However, the relatively weak magnetic fields of these devices (1–2 T) results in low sensitivity and significant peak overlap in
1H
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Benchtop NMR spectrometers with sub-ppm spectral resolution have opened up new opportunities for performing NMR outside of the standard laboratory environment. However, the relatively weak magnetic fields of these devices (1–2 T) results in low sensitivity and significant peak overlap in
1H NMR spectra. Here, we use hyperpolarised
13C{
1H} NMR to overcome these challenges. Specifically, we demonstrate the use of the signal amplification by reversible exchange (SABRE)
parahydrogen-based hyperpolarisation technique to enhance the sensitivity of natural abundance 1D and 2D
13C{
1H} benchtop NMR spectra. We compare two detection methods for SABRE-enhanced
13C NMR and observe an optimal
13C{
1H} signal-to-noise ratio (SNR) for a refocused INEPT approach, where hyperpolarisation is transferred from
1H to
13C. In addition, we exemplify SABRE-enhanced 2D
13C benchtop NMR through the acquisition of a 2D HETCOR spectrum of 260 mM of 4-methylpyridine at natural isotopic abundance in a total experiment time of 69 min. In theory, signal averaging for over 300 days would be required to achieve a comparable SNR for a thermally polarised benchtop NMR spectrum acquired of a sample of the same concentration at natural abundance.
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