Enhancing benchtop NMR spectroscopy by means of sample shifting
Benchtop NMR spectrometers have become widely available over the last decade. They are now used successfully in various branches of chemistry. Their popularity continues to grow due to their low price and almost zero running costs. However, benchtop spectrometers perform much less effectively than the high-field spectrometers used in NMR labs for several decades. In this article we present a solution for boosting the sensitivity of benchtop NMR spectrometers in a multi-scan experiment and improving its capabilities in quantitative measurement. Our solution involves the synchronized shifting of a sample to preserve its high nuclear polarization during the measurement. We performed several experiments using different samples to confirm this improved performance: an1H NMR experiment for 4,4-Dimethoxy-2-butanone, and13C NMR experiments for benzyl salicylate,liquid pharmaceutical product Acerin (skin solution), and a mixture of m-Anisaldehyde and (R)-(+)-Limonene.
